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1

Mikrokontroler – narzędzie bardzo przydatne w pracach badawczych

Matusik J.

Nafta-Gaz

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2018

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R. 74, nr 5

391--398

PL

W artykule przedstawiono charakterystykę mikrokontrolerów 8-bitowych z rodziny AVR. W szczególności położono nacisk na to, aby pokazać ogromne możliwości tych układów w aspekcie wykorzystania ich w codziennym funkcjonowaniu laboratorium badawczego. W pierwszej części dokonano ogólnej charakterystyki mikrokontrolerów oraz podzespołów współpracujących z tymi układami. Następnie przedstawiono sposób praktycznego wykorzystania mikrokontrolera na przykładzie hipotetycznego stanowiska badawczego.

EN

This article presents the characteristics of 8-bit microcontrollers from the AVR family. In particular, emphasis was placed on showing the great potential of these systems in terms of their use in the everyday functioning of a research laboratory. In the first part, the general characteristics of the microcontrollers and the subassemblies cooperating with these systems, were made. An example of the practical use of a microcontroller is shown on the example of a hypothetical test stand.

2

Chemical Examination of Fly Ash and Bottom Ash Derived from Incineration of Hazardous Waste

Kępys W., Wisła-Walsh E., Matusik J.

Inżynieria Mineralna

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2018

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R. 19, nr 1

221--233

EN

The content of heavy metals in solid residues from the incineration of hazardous waste affects the quality of the environment including soil and water and – most importantly – human health. The chemical composition is often decisive for the further management of the waste, which involves its direct use or conversion into an environmentally safe form. Therefore, the chemical and mineralogical composition of fly and bottom ash from the incineration of hazardous waste was examined. In addition, the results of leaching tests for heavy metals, Cl- and SO42- were performed. The obtained results indicate that the dominant components are SiO2, CaO, Al2O3, Fe2O3, SO3 and Cl-. Partitioning was observed for heavy metals such as Cr(III), Cu(II), Zn(II), Ni(II), Pb(II) and Cd(II) between fly ash and bottom ash. The leaching results showed a lower amount of heavy metals in eluates from bottom ash than fly ash as a result of their presence in the glassy phase.

PL

Zawartość metali ciężkich w stałych pozostałościach ze spalania odpadów niebezpiecznych powoduje, że są to odpady mogące negatywnie wpłynąć na jakość środowiska naturalnego jak i na zdrowie ludzi. Dodatkowo właściwości często decydującą o dalszym postępowaniu z tymi odpadami, polegającymi na ich bezpośrednim wykorzystaniu czy też przekształceniu w formę bezpieczną dla środowiska i/lub posiadającą cechy umożliwiające ich wykorzystanie. Z tego względu przebadano właściwości fizykochemiczne popiołów lotnych i żużli pochodzących z przemysłowej spalarni odpadów niebezpiecznych. W artykule przedstawiono wyniki badań zawartości głównych składników i metali ciężkich, analizy mineralogicznej i morfologicznej oraz wymywalności. Badania pokazują, że dominującymi składnikami są SiO2, CaO, Al2O3, Fe2O3, SO3, Cl. Zaobserwowano różnice w lokowaniu się metali ciężkich jak Cr, Cu, Zn, Ni, Pb i Cd pomiędzy popiołami lotnymi a żużlami. Wyniki wymywalności wskazują na mniejszą ilość wymywanych metali ciężkich z żużli niż z popiołów lotnych w efekcie występowania ich w fazie szklistej żużli.

3

Optymalny dobór gazomierzy miechowych przez operatora systemu gazowniczego

Matusik J., Jaworski J.

Nafta-Gaz

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2017

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R. 73, nr 4

274--286

PL

W artykule omówiono wybrane charakterystyki metrologiczne gazomierzy miechowych, które w istotny sposób wpływają na ilość nierozliczonego gazu. Zaprezentowano też aplikację, która na podstawie wprowadzonych charakterystyk metrologicznych danego gazomierza pozwala oszacować skalę wyżej wymienionego zjawiska. Informacją zwrotną z aplikacji jest analiza ekonomiczna uwzględniająca koszty zakupu gazomierza oraz wielkość zysków lub strat związanych z jego funkcjonowaniem w całym okresie eksploatacji. Porównując w ten sposób kilka typów gazomierzy, kupujący (operator systemu gazowniczego) może dokonać takiego wyboru, który w bliższej lub dalszej przyszłości przełoży się na wymierne korzyści finansowe.

EN

In the article selected metrological characteristics of diaphragm gas meters, which significantly affect the amount of unaccounted gas were discussed. An application which allows to estimate the scale of this phenomenon based on the input of metrological characteristics of the meter, has been presented in this article as well. The feedback from the application is the price balance that takes into account the cost of purchasing the gas meter and the amount of profits or losses, related to its functioning during the whole period of operation. Comparing a few groups of meters in such a way, the buyer can make a more qualified choice, which sooner or will translate into tangible financial benefits.

4

Halloysite composites with Fe3O4 particles: the effect of impregnation on the removal of aqueous Cd(II) and Pb(II)

Maziarz P., Matusik J.

Mineralogia

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2017

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Vol. 48, iss. 1/4

107--126

EN

In this study, halloysite-Fe3O4 composites were synthesized by a chemical-precipitation method to facilitate magnetic separation of the sorbents from aqueous solution. The research focused on the effect of Fe3O4 phase on the halloysite sorption properties. The X-ray diffraction (XRD) results confirmed successful deposition of Fe3O4 particles on a halloysite surface. They showed that the coating with Fe3O4 particles enhanced the halloysite adsorption affinity toward Cd(II) and Pb(II). The highest adsorption capacity was determined for the composites having 10% of the surface deposited with Fe3O4. In this case, the adsorption capacity for Cd(II) and Pb(II) was 33 and 112 mmol•kg-1, respectively. The point of zero charge (pHPZC) and desorption results indicated that the removal mechanism of metals is mainly related to chemisorption involving reaction with hydroxyls of either halloysite or Fe3O4 phase. The ion exchange is of limited importance due to the low cation exchange capacity (CEC) of halloysite - Fe3O4 composites.

5

Efficiency of Pb(II) and Mo(VI) removal by kaolinite impregnated with zero-valent iron particles

Rybka K., Suwała K., Maziarz P., Matusik J.

Mineralogia

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2017

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Vol. 48, iss. 1/4

71--86

EN

In this work, kaolinite modified with zero-valent iron was synthesized and used as a sorbent for Pb(II) and Mo(VI) removal from aqueous solutions. The obtained material was characterized by X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy. The methods revealed successful modification by the Fe0 particles precipitation on the surface of well-ordered kaolinite. The sorption experiment results showed a significant increase of sorption capacity in relation to the raw kaolinite. The kaolinite with 25% content of Fe0 was found to be the best material for Pb(II) and Mo(VI) removal, resulting in approximately 500 mmol•kg-1 and 350 mmol•kg-1 sorption, respectively. The possible mechanisms responsible for metals’ removal were identified as reduction by Fe0 ‘core’ and adsorption on the iron hydroxides ‘shell’. The study indicated that the obtained material is capable of efficient Pb(II) and Mo(VI) removal and may be an interesting alternative to other methods used for heavy metals’ removal.

6

Na-montmorillonite modified with ammonium salts and azobenzene as a photoactive nanomaterial

Koteja A., Matusik J.

Geology, Geophysics and Environment

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2016

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Vol. 42, no. 1

87--88

EN

Modification of inorganic solid structures (e.g. minerals) with organic molecules is a constantly developed topic in material sciences. The organic functionalization leads to the production of new materials with integrated properties of both the organic and inorganic component. In the presented study we have modified a Na-montmorillonite with alkylammonium surfactants and subsequently azobenzene, in order to obtain a nanomaterial that shows response to UV radiation. Azobenzene is a photoswitchable organic molecule capable to change its conformation upon UV radiation from the trans- to cis-azobenzene isomer. This reaction is coupled with a change of the molecules shape and dimensions (Klajn 2010). The montmorillonite is a layered aluminosilicate that serves as an excellent host structure for organic guest species. Due to the net negative layer charge it shows the ability to swell and to exchange the originally present interlayer cations. These properties allow the intercalation of bulk organic molecules and to control their arrangement. Much attention has been paid to the possibility of transferring the photoswitching ability of organic molecule into the motion of the whole organo-mineral structure (Heinz et al. 2008). Such nanoswitch is particularly appealing as it is controlled with radiation – remotely and at a precise location. The efficiency of a synthesized nanoswitch depends on an accurate selection of the host and guest component. The target of this study to test a series of organic surfactants and to establish a modification pathway that leads to obtaining a material most promising in the view of its photoresponsive behavior. The montmorillonite modification was performed in a two-step procedure, as the direct intercalation of a nonionic azobenzene is not possible. First, the Na-montmorillonite (denoted SWy) was ion-exchanged with trimethylalkylammonium cations abbreviated C n and benzyldimethylalkylammonium cations – BC n , where n refers to the number of carbon atoms in the alkyl chain and is equal to 12, 14 or 16. In the second step the organo-montmorillonites were reacted with azobenzene (AzBz) for 24 h at 120°C in a hermetically closed teflon vessel. The yellowish products were characterized with the X-Ray diffraction (XRD), the infrared spectroscopy (FTIR) and CHN elemental analysis. In all cases the intercalation of the ammonium cation caused an increase of the montmorillonites basal spacing ( d 001 ). The d 001 values were equal to 16.4 Å, 18.2 Å and 20.5 Å for SWy-C 12 , SWy-C 14 and SWy-C 16 , respectively. The samples modified with the BC n cations showed ~1.5 Å larger basal spacing, due to the presence of the benzyl group in the intercalated molecule. A linear relationship was observed between the d 001 value and the alkyl chain length of the introduced salts. This suggests that the organic cations formed paraffin-type aggregates in the interlayer (Ogawa et al. 1999) where the molecules are inclined to the layer surface. The FTIR spectra of modified SWy sample showed intense bands corresponding to CH 2 vibration modes. Along with the increasing alkyl chain length the CH 2 stretching bands shifted towards lower energies. This is an effect of growing packing density of alkylammonium molecules in the interlayer (He et al. 2004) and it is coupled with straightening of the alkyl chains due to transformation of disordered gauche conformer to the ordered all-trans conformer (Vaia et al. 1994). It can be concluded that the longer alkyl chains (C 16 and BC 16 ) form more ordered, solid-like aggregates in the interlayer space. The molar content of organic molecules was calculated basing on the CHN elemental analysis. The amount of intercalated alkylammonium cations was nearly equal to the cation exchange capacity (CEC) of montmorillonite – 88.9 meq/100 g. The reaction with azobenzene was most effective for montmorillonite modified with the alkylammonium cations having the longest chains as confirmed by the XRD patterns. The d 001 values of SWy-C 16 and SWy-BC 16 samples after reaction with AzBz increased to 36.9 Å and 35.9 Å, respecively. Well resolved and intense (001) peaks as well as the presence of the 2 nd and 3 rd order reflections indicated a highly ordered structure of these intercalates. On the contrary, diffraction peaks were less resolved and broadened for samples prepared with the shorter C 12 , C 14 , BC 12 and BC 14 molecules after reaction with AzBz. Based on these results, it is assumed that the long chain alkylammonium ions are more effective surfactants for the further intercalation of azobenzene into the montmorillonites interlayer space. The obtained highly ordered structures are promising materials for application as photo-actuated nanoswitches.

7

Department of Mineralogy, Petrography and Geochemistry

Matusik J., Rzepa G.

Geology, Geophysics and Environment

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2016

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Vol. 42, no. 2

218--222

8

Removal of selected anions by raw halloysite and smectite clay

Prokop A., Maziarz P., Matusik J.

Geology, Geophysics and Environment

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2015

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Vol. 41, no. 1

125--126

EN

The structure of clay minerals consists of tetrahedral and octahedral sheets, which can form 1:1, 2:1, and 2:1:1 layers. The halloysite, which belongs to the kaolin group, is composed of 1:1 layers while smectite group minerals contains 2:1 dioctahedral layer. The presence of numerous active centers on mineral surfaces and/or in the interlayer spaces allows them to attract and exchange ions from aqueous solutions. This makes them suitable for removal of harmful/toxic ions such as P(V), As(V), and Cr(VI) (Mozgawa et al. 2011, Matusik 2014) or Pb(II), Cd(II), Zn(II), and Cu(II) (Bhattacharyya & Gupta 2008, Matusik & Wcisło 2014) from wastewaters. The aim of this work was to examine the sorption capacity of natural halloysite and smectite clay towards P(V), As(V), and Cr(VI).Two samples used in this study were collected from Polish deposits. Natural halloysite (H) was obtained from Dunino deposit (located near Legnica in SW Poland), while smectite clay (SC) was obtained from Bełchatów Lignine Mine where it forms an overburden cover. For both raw samples the X-ray diffraction (XRD) patterns and infrared absorption (FTIR) spectra were collected. The sorption of P(V), As(V), and Cr(VI) was conducted as a function of anions concentrations ranging from 0.05 to 50 mmol/L for initial pH of 5 in a single−element system. The suspension of H or SC and corresponding aqueous solution (solid/solution ratio: 20 g/L) was shaken for 24 h at 25°C. Afterwards the anions concentration in the supernatant solution was measured using colorimetric methods. The P(V) and As(V) concentration was determined with the molybdenum blue method, whereas Cr(VI) concentration was measured with diphenylcarbazide method. The XRD pattern of the H sample showed a basal peak at 7.20 Å, which confirms the presence of dehydrated halloysite (7 Å). In turn, the SC exhibited a peak centered at ~12.5 Å with an asymmetric profile starting from ~15.0 Å. Such ref lection suggests the presence of smectite which has both Na+and Ca2+cations in its interlayer space. The IR spectra of the H showed bands specific for kaolin group minerals related to the OH-stretching region (3700−3620 cm−1), vibrations of water molecules (~1630 cm−1) and bands associated with stretching and bending vibrations of aluminosilicate framework (1200−400 cm−1). The IR spectrum of SC showed bands specific for smectite minerals; i.e. 3623 cm−1band attributed to OH hydroxyl located inside the 2:1 layer, and broad band centered at ~3400 cm−1due to interlayer water surrounding cations. Also the structural vibrations of the 2:1 layer were observed in the 1200−400 cm−1 region.The results of the experiment indicated that the sorption capacity of both H and SC samples was relatively high. The highest uptake of P(V) was measured for both materials and it was equal to 201 and 256 mmol/kg, respectively for H and SC. The sorption capacity of H and SC towards As(V) was 168 and 96 mmol/kg, respectively. The 126 sorption of Cr(VI) by H and SC equaled 36 and 104 mmol/kg, respectively. The sorption isotherms were fitted to the Freundlich model (Freundlich 1906) with an exception of P(V) which sorption on H sample was described by Langmuir model (Langmuir 1916). The specific surface areas (SBET) of studied materials were similar: H = 49.52 m2/g and SC = 69.10 m2/g. The sorption centers that may attract anions in both H and SC samples were limited due to isomorphic substitutions in tetrahedral and/or octahedral sheets. This will generate positively charged sites and attract cations rather than anions. It is believed that the mechanism responsible for the adsorption of anions on both materials is mainly surface complexation at t he crystals edges (Bradl 2004). The sorption capacity of H and SC samples was lower than that reported for hydrotalcite − based anion − exchange materials (HTLc). For comparison, the sorption capacity towards P(V), As(V) and Cr(VI) on uncalcined HTLc was 498 mmol/kg (Kuzawa et al. 2006), 596 mmol/kg (Wu et al. 2013) and 314 mmol/kg (Alvarez-Ayuso & Nugteren 2005), respectively. Nevertheless, the examined mineral samples might be used as sorbents for industrial wastewater treatment involving removal of P(V) and As(V).

9

Preparation and characterization of azobenzene-smectite photoactive mineral nanomaterials

Koteja A., Matusik J.

Geology, Geophysics and Environment

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2015

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Vol. 41, no. 1

99--100

EN

Smectites are 2:1 layered minerals built of one octahedral sheet located between two tetrahedral sheets. The layer charge derived from the isomorphic substitutions in the mineral structure is compensated by the interlayer cations. The capability to exchange the interlayer cations is an important property of smectites as it enables to design and produce new nanomaterials through their modification with organic compounds. Such hybrid materials are highly desirable in industry and environmental protection due to their specific properties that may be designed in nanoscale. Preparation of photoactive materials using intercalation of layered minerals, mainly synthetic micas, with azobenzene and other azocompounds was proposed previously (Fujita et al. 2003, Ogawa et al. 2003, Heinz et al. 2008). Azobenzene molecules show a change in their shape and dimensions upon the UV irradiation, what may affect the structure of host mineral. The photoactive materials may find application in nanotechnology as molecular nanoswitches and nanosensors controlled by UV radiation (Klajn 2010). The objective of this study was to prepare azobenzene-smectite intercalation compounds. The results of structural and chemical characterization of obtained materials are crucial for further improvement of their photoresponsive properties.The Na-montmorillonite (SWy), Camontmorillonite (STx), beidellite (BId) and synthetic laponite (SynL) were used in the experiments. The modification procedure involved (1) the intercalation of smectites with hexadecyltrimethylammonium bromide (C16), and (2) insertion of azobenzene into the interlayer space. The reaction with C16, in amount equal to 1.0 CEC (cation exchange capacity) of the smectite, was performed in an aqueous suspension (20 g/L) for 2 h in 60°C. The obtained organosmectites were prepared as thin films on the glass plates and reacted with azobenzene in a teflon vessel at ~100°C for 24 h. In such conditions the azobenzene vaporizes and penetrates the interlayer space of the organomineral. The azobenzene/smectite weight ratio was equal to 0.2. The chemical and structural analyses of all obtained samples were carried out using X-ray diffraction (XRD), infrared spectroscopy (FTIR), and CHN (carbon-hydrogen-nitrogen) elemental analysis. The increased amount of nitrogen and carbon in modified samples confirmed the occurrence of intercalation process of both the ammonium salt and the azobenzene. Moreover, new bands appeared in the infrared spectra of the C16-smectites at ~2924 cm−1 and ~2851 cm−1 due to the C-H stretching vibrations in the C16 molecules. The spectra of azobenzene intercalation compounds showed add it ionally a series of bands corresponding to the vibrations characteristic for the azobenzene 2015, vol. 41 (1): 99–100100molecule at ~3061 cm−1, ~1581 cm−1, ~1455 cm−1, and ~1302 cm−1. The basal spacing of tested minerals increased after the C16 intercalation, as confirmed by XRD analysis. The increase was equal to 6.1 Å, 3.3 Å, 4.1 Å and 3.5 Å for SWy, STx, BId and SynL samples, respectively. This suggests nearly horizontal arrangement of the C16 molecules and formation of a monolayer in the smectite’s interlayer space. Introduction of azobenzene lead to a further increase of d001. The increase was visibly different for all the samples and it was equal to 7.0 Å, 15.0 Å, 21.7 Å and 23.5 Å for SWy, STx, Bid, and SynL samples, respectively. The arrangement of organic molecules in the interlayer space is influenced by a number of factors including (1) type of the mineral, (2) layer charge and its location in the layer, and (3) the amount and arrangement of the cationic surfactant (Klapyta et al. 2001, Lagaly et al. 1976). A correlation between azobenzene location in the interlayer space and the photo-response behaviour of tested materials will be the subject of further studies.

10

A comparative study on the removal of Pb(II), Zn(II), Cd(II) and As(V) by natural, acid activated and calcinated halloysite

Maziarz P., Prokop A., Matusik J.

Geology, Geophysics and Environment

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2015

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Vol. 41, no. 1

108--109

EN

With the intensive development of the global industry trace elements like lead, zinc, cadmium and arsenic spread and infiltrate into soil and water, what results in contamination. Clay minerals play an important role in the environment as natural adsorbents. This is, due to their ability of attracting and accumulating ions from water solutions by their structure, what leads to their immobilization. Halloysite is a clay mineral, belonging to the kaolin group minerals. Its structure is composed of stacked 1:1 layers built from octahedral (alumina) and tetrahedral (silica) sheets. Due to the fact that Poland has several kaolin deposits it is important to undertake research concerning possibility of using them as a natural scavenger of pollutants (Matusik & Bajda 2013, Matusik & Wścisło 2014). Thus, the purpose of the research was to investigate the sorption affinity of natural, acid activated and calcinated halloysite toward Pb(II), Zn(II), Cd(II) and As(V). In the study three mineral samples were chosen: natural halloysite – H, acid activated halloysite – HA and calcinated halloysite – HC. The H sample used in the study came from Polish deposit located in Dunino near Legnica which is owned and exploited by the Intermark Company. The last two samples are produced by Intermark on an industrial scale, by modifying H sample. The chemical activation of halloysite was carried out by sulphuric acid treatment at 100°C for 3 h, whereas the calcination temperature was 650°C. The materials were characterized using XRD and FTIR methods. Additionally the cation exchange capacity (CEC) and specific surface area (SBET) were measured. The CEC of tested materials were measured by adsorption of methylene blue. The SBET was determined on the basis of the low temperature nitrogen adsorption isotherm measured at −196°C and calculated in accordance with the Brunauer-Emmet-Teller (BET) methodology. The materials sorption affinity towards Pb(II), Zn(II), Cd(II) and As(V) was investigated. Experiments were carried out at pH 5. After mixing 50 mg of each material with 2.5 ml of appropriate solution (20 g/L – solid/solution ratio), sample portions were shaken for 24 h at room temperature. The concentration of metals – Pb(II), Cd(II) and Zn(II) in supernatant solutions was determined using AAS method while the As(V) was measured using colorimetric molybdenum blue method. The XRD pattern of the H sample showed a basal peak at 7.20 Å, which is attributed to dehydrated halloysite-7(Å). There were no significant changes in the XRD pattern of HC sample, which indicated that there were no significant changes in the clay structure due to calcination. In contrast, the XRD pattern of HA sample showed a decrease in intensity of ~7.20 Å peak of halloysite and the appearance of new peak at 7.63 Å was observed. Also, there were changes in the 19–25° 2θ region, what is an effect of structural disorder caused by sulfuric acid treatment. It is worth notifying that the FTIR spectra of H and HC samples did not differ significantly. In turn, the bands changes for the HA are noticeable, which is in accordance with XRD results. After acid treatment the bands shape and intensity in 1300–1000 cm−1 region has changed indicating structural disorder of tetrahedral sheet. The spectra revealed that, the octahedral sheet and OH hydroxyls were not significantly altered by acid treatment. The HA sample exhibited the largest SBET(171. 6 m2/g) while the SBET for the H sample was the lowest (49.5 m2/g). The calcination led to slight increase of SBET value to 52.1 m2/g in com-parison to the H sample. The CEC results showed that differences between H (8.79 ± 0.1 meq/100 g) and HC (8.19 ± 0.2 meq/100 g) samples are insignificant, moreover the CEC of H sample is slightly higher. Such decrease can be explained by the loss of some the cation exchange sites, induced by heat treatment (Ho & Handy 1964). The increase in CEC value was observed for the HA sample (10.69 ± 0.5 meq/100 g). Sorption mechanism for raw halloysite can take place via ion-exchange and surface complexation through silanol Si-OH and aluminol Al-OH groups. The Pb(II) ions are more likely to hydrolyze and create PbOH+ forms, which may link to deprotonated groups. This process is called surface complexation. Heavy metals such as Zn(II) and Cd(II) tend to adsorb through ion-exchange (Srivastava et al. 2005). The sorption capacity for H sample was found to follow the sequence As(V) > Pb(II) > Cd(II) > Zn(II). In the case of cations, this behavior reflects the cations hydrolysis constants, which are equal to 7.71, 10.08, and 8.96 respectively. The sorption ca-pacity for H sample reached 168.4 mmol As/kg, 37.2 mmol Pb/kg, 3.7 mmol Cd/kg and 1.9 mmol Zn/kg. The sorption onto HC sample was found to be the following: Pb(II) ≈ Zn(II) > Cd(II) > As(V). Comparing sorption results for HC to the results for H sample, the increase of sorption for all tested heavy metals was observed. The sorption of cations reached an equilibrium equal to: 219 mmol Pb/kg, 212 mmol Zn/kg and 134 mmol Cd/kg. The sorption of As(V) decreased slightly in com-parison to H sample. The acid activation resulted in an increase of active sites capable for Pb(II) adsorption and a decrease of active sites responsible for As(V) adsorption. Sorption equilibrium reached 235 mmol Pb/kg and 66 mmol As/kg. The results obtained for Zn(II) and Cd(II) indicated that sorption was not observed which may be due to lack of ion-exchange sites. The explanation of this behavior requires further studies. It is was worth to underline the highest sorption capacity of H sample towards As(V) which is most likely due to surface complexation. The results indicated that depending on the type of pollutants an appropriate type of halloysite-based sorbent needs to be chosen.

11

The kinetics of heavy metals immobilization by modified halloysite

Maziarz P., Matusik J.

Geology, Geophysics and Environment

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2014

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Vol. 40, no. 1

108--109

EN

Halloysite is a clay mineral, belonging to the kaolinite group. Its structure is composed of stacked 1:1 layers built from octahedral (alumina) and tetrahedral (silica) sheets, linked through hydrogen bonds formed between oxygen atoms of tetrahedral sheet and inner surface OH groups of octahedral sheet. Due to the fact that Poland has several kaolin deposits, it is important to undertake research concerning possible application after appropriate modification (Matusik & Bajda 2013, Matusik & Kłapyta 2013, Matusik et al. 2013). Beyond harmful properties, the decisive factor in the selection of heavy metals was their high prevalence in the environment. The purpose of the research was to analyze the kinetics of heavy metals immobilization by natural and modified halloysite. The mineral (H) used in the study came from Polish deposit located in Dunino near Legnica, which is owned by the Intermark company. The sample, apart from halloysite, which exhibits a tubular morphology, contains kaolinite forming plates. The modification procedure involved two following steps. Firstly, material was intercalated with dimethyl sulfoxide (DMSO) by mixing 12.5 g of mineral with 90 mL DMSO and 10 mL H2O (HDMSO). The second step involved grafting process, in which the HDMSO was refluxed with 150 ml of diethanolamine (DEA) for 24 h at 180°C under argon flow. Afterwards, the final sample (HD) was washed with isopropanol and subsequently with water to remove DMSO remnants and the excess of DEA. The materials were characterized using XRD and IR methods. The materials sorption affinity towards Pb(II), Zn(II), Cd(II) and Cu(II) was investigated. The experiment was carried out for a mixture of all four metals (multi-element system) at equal 1 mmol/L concentration at initial pH 5.2. The material either H or HDEA (1 g) was mixed with 50 mL of solution (20 g/L - solid/solution ratio). The suspension aliqouts were collected after 0.5, 1, 1.5, 2, 3, 4, 5, 6, 8, 10, 15, 20, 30 min, filtered immediately, and further analyzed using AAS method.The XRD patterns showed that the modification did not alter all halloysite layers. The 10.4 Å peak of the new complex, and the 7.3 Å peak of raw mineral were observed. The IR spectra of H sample in 3700-3600 cm-1 region revealed four distinct bands attributed to different vibration modes of inner surface and inner hydroxyls. After DMSO intercalation new bands at 3540 cm-1 and 3503 cm-1 were noticed connected to interlayer hydrogen bonding S=O...HO between DMSO molecules and OH hydroxyls of the octahedral sheet. The bands at 3022 cm-1, 2936 cm-1, and 2918 cm-1, were due to C-H stretching vibrations of DMSO methyl groups. The IR spectra after DEA grafting, showed the disappearance of bands related to DMSO molecules indicating their removal. The adsorption behavior of tested heavy metals onto raw and modified halloysite differs. In the experiment with H sample the equilibrium was achieved almost immediately. On the other hand, in the case of HD sample the sorption increased gradually and the equilibrium was reached after about 30 min. The relatively slowest uptake was particularly noticeable for Cu(II) and Pb(II). The sorption on raw halloysite may take place through surface complexation and/or ion-exchange. The sorption on natural halloysite was found to follow the sequence Pb(II) > Zn(II) > Cu(II) ≈ Cd(II), which reflects the cations hydrolysis behavior. After 30 minutes the sorption capacity for H sample reached 15 mmol Pb/kg, 6 mmol Zn/kg, 1.5 mmol Cu/kg, 1 mmol Cd/kg. The final pH decreased to 4.2 confirming the protons release characteristic for surface complexation mechanism. The sorption on modified halloysite was found to be the following: Cu(II) > Pb(II) > Zn(II) ≈ Cd(II). The sorption reached an equilibrium equal to: 25 mmol Cu/kg, 20 mmol Pb/kg, 10 mmol Zn/kg and 8 mmol Cd/kg. It is worth to mention that 16-fold increase for Cu(II) and 8-fold increase for Cd(II) were noticed. In particular the Cu(II) sorption increase is due to formation of Cu(II)-DEA complexes. The final pH of solution increased to 5.3 due to competitive sorption of protons to amine nitrogen of the DEA.

12

Quantitative determination of ammonium salts in organo-zeolites by infrared spectroscopy

Szala B., Bajda T., Matusik J.

Geology, Geophysics and Environment

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2014

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Vol. 40, no. 1

131--132

EN

In recent years, the feasibility of using fly ash from the combustion of coal for the synthesis of zeolites has been studied (Belviso et al. 2010, Derkowski et al. 2010). One of the many uses of zeolites is to leverage their properties to act as organic sorbents (Bowman 2003). Unfortunately, the sorption process of organic substances on zeolites is hampered by the negatively-charged surface of the crystallites (Jashua & Bowman 2009). In order to increase the chemical affinity of the zeolite's surface to the organic molecules, its modification by organic surfactants is necessary. This leads to the formation of an organo-mineral complex with improved sorption properties. It has been found that organo-zeolites may be used to remove volatile compounds in a pure form, and those which occur in nature as impurities of air, water and soil (Damjanovic et al. 2010, Vidal et al. 2012). Therefore, it seems reasonable to search for an organo-zeolite sorbent which is cheap, efficient and environmentally-friendly (Apreutesei et al. 2008). The zeolites modification takes place only on the outer surface of the crystallites as the ammonium salts' molecules are too large to enter the zeolite's channels. Therefore, external cation exchange capacity (ECEC) is an important property in the synthesis of organo-zeolites. The type of surfactant introduced and its amount, often given by ECEC values, is crucial-subsequently leading to the formation of materials differing in sorption properties. Thus, it is essential to determine the effectiveness of modification by examining the amount of surfactant adsorbed on zeolites' surface. In the experiments, a Na-P1 zeolite synthesized from fly ash remaining after coal combustion and a natural Ukrainian zeolite were transformed into organo-zeolites. This involved the replacement of original exchangeable cations (K+, Na+, Ca2+, Mg2+) by organic cations from the following salts: hexadecyltrimethylammonium bromide (HDTMA) and octadecyltrimethylammonium bromide (ODTMA) in amounts equal to 0.25, 0.50, 0.75 and 1.00 of ECEC. ECEC for synthetic zeolite Na-P1 was determined, and it was 24.4 meq/100 g, which corresponds to a single layer (1.0). The aim of this study was to use the infrared spectroscopy (FTIR) to determine the quantity of the surfactant adsorbed on the crystallites surface. The FTIR spectra were collected by a Thermo Scientific Nicolet 7600 spectrometer using the DRIFT technique. The CHN analysis was used to investigate the modification efficiency through quantification of the attached surfactant. The normalized intensity of selected bands attributed to C-H stretching vibrations in the 3,000-2,800 cm-1 region was compared with CHN results. The results revealed a high correlation (R2 > 0.99) between spectroscopic and chemical analyses. The band intensities compared with the efficiency of modification enabled to obtain appropriate calibration curves. This proved that FTIR could be used for a fast determination of the surfactants amount in the obtained organo-zeolites.

13

Improved copper sorption on grafted kaolinites of different structural order

Koteja A., Matusik J.

Geology, Geophysics and Environment

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2014

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Vol. 40, no. 1

96--97

EN

Kaolin group minerals exhibit relatively low sorption capacity as the migration of ions and their sorption in the interlayer space is not possible. The ions attraction is limited to the particles faces and edges through surface complexation and ion-exchange mechanisms. The ongoing research on functionalized kaolinites enabled to synthesize new nanomaterials with possible applications in industry and environmental protection. The modification procedures mainly involve structure alteration by intercalation and/or grafting processes. It is worth to underline that kaolinite 1:1 layer has exposed inner surface hydroxyls which are susceptible for reactions with selected organic molecules and as a results new materials with interesting properties may be obtained. Heavy metals in excessive amount are toxic and may lead to serious health problems. Thus, the purification of heavy metal contaminated aqueous solutions is of environmental importance. The aim of the study was to examine the sorption properties of kaolinites grafted with selected aminoalcohols towards Cu(II). For the experiments, two types of Polish kaolinites were chosen: well ordered type from Maria III deposit (M) (located about 20 km SW from Bolesławiec) and poorly ordered type from Jaroszów deposit (J) (located about 10 km NE from Strzegom). The modification consisted of (i) a preparation of kaolinite-dimethyl sulfoxide intercalate (MDMSO and JDMSO) and (ii) its further grafting with diethanolamine (DEA) or triethanolamine (TEA) (Letaief & Detellier 2007). The synthesized MDEA, MTEA, JDEA and JTEA samples were examined using XRD, IR and CHNS methods. The Cu(II) sorption equilibrium experiments were performed for the 0.005-10.0 mmol/L concentration range at room temperature (initial pH 5). The suspensions (20 g/L) were shaken for 24 hours. Afterwards, the Cu(II) concentration was measured using AAS method. The d001 reflections for the MDEA, MTEA, JDEA and JTEA increased from 7.2 Å (M and J samples) to 10.2 Å, 10.8 Å, 10.1 Å and 11.0 Å, respectively which confirmed the formation of grafted compounds. The presence of organic molecules resulted in an appearance of C-H stretching bands (2800-3000 cm-1) in the IR spectra. Moreover, changes in the O-H stretching region (3600-3700 cm-1) were also noticed due to interaction of aminoalcohols with kaolinites hydroxyls. An assumption was made that the sorption of cations will take place by the nitrogen lone electron pair of the grafted DEA or TEA. Thus, the theoretical sorption capacity associated with nitrogen was calculated on the basis of CHNS analysis and was the following: 184 mmol/kg (MDEA), 223 mmol/kg (MTEA), 122 mmol/kg (JDEA) and 323 mmol/kg (JTEA). The highest Cu(II) sorption was observed for the JTEA sample: 119 mmol/kg, while for the J and JDEA samples it reached 65 mmol/kg and 88 mmol/kg, respectively. The sorption improvement was less pronounced for materials based on the M sample. Both for the pure M sample and the MTEA sample, the sorption capacity was equal to ∼62 mmol/kg, while for the MDEA sample it was higher and reached 72 mmol/kg. It can be concluded that the performed modifications have improved the kaolinites sorption capacity. The improvement was due to cations attraction by the nitrogen lone electron pairs after their migration into the interlayer space. Worth emphasizing is that the Cu(II) ions readily form Cu-aminoalcohol complexes in aqueous solutions (Karadag et al. 2001). As a result of such mechanism, the pH value has increased, which is attributed to competitive protons sorption. The adsorption energy, estimated on the basis of Dubinin-Radushkevich equation, for all the reactions was in the 10-14 kJ/mol range. This indicates that the adsorption energy corresponds to energies characteristic for the ion exchange reactions (Debnath & Ghosh 2007). In most cases the sorption isotherms followed the Langmuir model.

14

Competitive sorption of selected anions on modified halloysite

Prokop A., Matusik J.

Geology, Geophysics and Environment

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2014

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Vol. 40, no. 1

118--119

EN

Halloysite is a polytype of kaolinite exhibiting a 1:1 layered structure with the chemical composition of Al4Si4O10(OH)8. Synthesis of new materials based on kaolinites has received wide attention recently (e.g. Dedzo et al. 2012). Soluble forms of chromium, arsenic and phosphorus found in excessive amounts in waters are toxic and/or carcinogenic and may cause health problems. Thus, the aim of this work was to investigate the sorption of aqueous Cr(VI), As(V), and P(V) on natural halloysite and halloysite grafted with diethanolamine. Halloysite (H) sample was obtained from the Intermark Company which exploits the Dunino deposits formed as a result of basalt weathering, located in NW Poland near Legnica. The modification consisted of two steps. Firstly, the intercalate of the mineral with dimethyl sulfoxide (DMSO) was prepared. For this purpose 12.5 g of the mineral was dispersed in a mixture of 90 mL DMSO and 10 mL H2O for 5 days at room temperature (HDMSO sample). Secondly, the HDMSO was refluxed with diethanolamine (DEA) (100 g/L ratio) for 24 h at 180°C under argon flow. The centrifuged product (HD) was washed with isopropanol and subsequently with water to remove unreacted DEA and DMSO remnants and dried at 65°C. The material was characterized using XRD, IR and SEM methods. Adsorption experiments were conducted at 5 mmol/L Cr(VI), As(V), and P(V) concentration in the single-element system for initial pH 3, 6, 9 and in mixed double-element system (1:1 anion molar ratio) for the initial pH 3. For the equilibrium studies, the H and HD samples were shaken in adequate solution (solid/solution ratio 20 g/L) for 24 h at room temperature. Afterwards, the supernatant solution was analyzed for anions. The Cr(VI) concentration was determined by 1.5-diphenylcarbazide method, while the P(V) and As(V) concentrations were determined by molybdenum blue method. The XRD confirmed the formation of an intercalate with DMSO as the characteristic d001 peak at 11.2 Å appeared. After DMSO treatment, the intensity of four distinct bands in the OH stretching region (3,700-3,600 cm-1), which are characteristic for the natural halloysite, changed as a result of interaction between the mineral and DMSO. Also the bands attributed to the C-H stretching vibrations of DMSO methyl groups were found at 3,021, 2,937 and 2,920 cm-1. The interlayer grafting of DEA led to fixing of basal spacing at 10.34 Å. After water washing the IR spectra showed only bands related to the grafted DEA molecules, which confirms the derivative stability (Matusik & Bajda 2013). As the cation exchange capacity (CEC) of the H sample is low, the adsorption process takes place mainly at the crystal edges. It was assumed that the protonated amine group of DEA will attract the anionie species. The results show that such modification does not improve the anion sorption properties of halloysite. The sorption increased only in case of Cr(VI) from 4 to 9 mmol/kg at initial pH 9 (single-element system). The highest sorption was observed in acidic system due to lack of competitive OH ions. In this case, sorption of Cr(VI) was 27 mmol/kg for H and 28 mmol/kg for HD. In contrast, the H adsorbed 108 mmol P(V)/kg in single-element system, while HD adsorbed only 50 mmol P(V)/kg. Adsorption of the As(V) was higher for the H sample and equal to 67 mmol/kg. A comparison of the obtained results for P(V) and As(V) to the sorption efficiency of HDT-MA-modified zeolites (respectively: 80 mmol/kg and 35 mmol/kg) and HDTMA-modified smectites (respectively: 75 mmol/kg and 45 mmol/kg) indicates, that the natural halloysite is a promising sorbent with regard to the studied anions (Mozgawa et al. 2011). In the single-element system the sorption increased as follows: P > As >>Cr. In turn, in the double-element system the competitive sorption was observed. Thus, the sorption of P(V) was lowered in the presence of Cr(VI), while in competitive P(V)-As(V) system the sorption of As(V) dominated. The mechanisms which contribute to the sorption were mainly surface complexation. Further investigation requires thermodynamic studies and the use of i.e. XPS (X-ray photoelectron spectroscopy).

15

Intercalates of kaolinite with ammonium salts and their interaction with aqueous Cr(VI) ions

Matykowska L., Matusik J.

Geology, Geophysics and Environment

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2012

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Vol. 38, no. 4

506--507

EN

Kaolinite is a dioctahedral aluminum silicate built from linked octahedral (alumina) and tetrahedral (silica) sheets, which form an asymmetrical 1:1 layer. Kaolinite is more often used as a base for the synthesis of new hybrid materials (Dedzo et al. 2012). Kaolinites modified with selected organic molecules are studied because of their potential application as environmental remediation materials and polymer nanoeomposite fillers (Matusik & Bajda 2013). Therefore the purpose of the study was to test the ability of kaolinite intercalation with ammonium salts to remove Cr(VI) from aqueous solution under different conditions. Additionally, information on the removal mechanism was obtained. Well ordered kaolinite from Polish Maria III deposit (M) was used for the experiments. The mineral intercalated with dimethyl sulfoxide (DMSO) was used as a precursor. The sample portions of 12.5 g were mixed with 90 mL of DMSO and 10 ml of H2O for 7 days at room temperature (MDS sample). The formed MDS intercalation compound was rinsed with CH3OH until all DMSO was removed from the interlayer space and the methoxy-kaolinite (KM sample) was synthesized (Matusik et al. 2012). Finally, the KM sample was centrifuged, the excess of methanol was removed and the wet KM was stirred in methanol solutions of the ammonium salts. For the experiments the following chlorides solution were used: 2M tetramethylammonium (TMA), 1M benzyldimethylhexadecylam-monium (B5) and 2M benzyltrimethylammonium (Bl). The formed materials were abbreviated as the salts. The TMA and Bl samples were washed with isopropanol to remove the excess of ammonium salt crystallized on the surface of the intercalates. In contrast to Bl and TMA, the B5 complex was not washed as isopropanol destroys its structure. All samples were dried at 60°C for 24 h. The products were characterized using powder XRD, IR, and CFfNS elemental analysis. The sorption of chromate on the modified kaolinite was measured spectrophotometrically using 1.5-diphenylcarbazide method as a function of Cr(VI) concentration (0.02-20 mM/L) at pH 5. The intercalates were shaken in prepared chromate solutions (ratio 20 g/L) for 24 h at 22°C. The XRD confirmed that methoxy--kaolinite was intercalated with ammonium salts, which was not possible for the raw kaolinite. The dml peak (7.2 A) increased to 14.7 A (Bl), 12.6 A (TMA) and 38.4 A (B5). The small molecules in the case of Bl and TMA complexes formed a monolayer in the interlayer space while the long chain B5 molecules were tilted with respect to 1:1 layers. The presence TMA, Bl and B5 in the mineral structure was confirmed by infrared spectroscopy (FTIR) as the organic bands in the 3120-2800 cm" region attributed to C-H stretching vibrations were registered. The changes in the position and intensity of the bands were also observed in the Si-0 vibrations region (1200-900 cm" ) due to salts incorporation. Results of CHNS analyses were used to determine the chemical formulas of the derivatives: Al2Si2O5(OH)379(OCH3)021[TMA]054, Al2Si2O5(OH)379(OCH3)021[Bl]038, Al2Si2O5(OH)3.79(OCH3)0.21[B5]0.59. The modification by ammonium salts enhanced the sorption capacity as compared to raw kaolinite where the sorption capacity reached only ~2 mM Cr(VI)/kg. For the TMA intercalate the maximum Cr(VI) sorption reached ~23 mM Cr(VI)/kg. For the Bl it was equal to ~73 mM Cr(VI)/kg and for the B5 it was significantly higher equal to -979 mM Cr(VI)/kg. Two possible Cr(VI) immobilization mechanism could be distinguished: ion exchange of Cr(VI) with Cl and surface precipitation of organic chromate. In the experimental pH range the HCrO^ ionic form of Cr(VI) dominates and it can be exchanged with Cl . The precipitation mechanism undoubtedly dominated in the case of B5 where a yellow precipitate of organic chromate appeared. The XRD studies performed on samples after sorption indicated the lack of

16

Halloysite-based material with improved cation sorption properties

Wścisło A., Matusik J.

Geology, Geophysics and Environment

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2012

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Vol. 38, no. 4

553--554

EN

Halloysite is 1:1 layered, dioctahedral phyllosilicate. It belongs to kaolinite subgroup of kaolinite-serpentine group. Halloysite is often defined as a hydrated phase of kaolinite. Two types of this mineral are distinguished: hydrated 10 A-halloysite, with water molecules in the interlayer space and dehydrated 7 A-halloysite. Widely conducted research on modified kaolin group minerals, either intercalates or grafted compounds with selected organic molecules opened many possibilities for using this layered aluminosilicate in industry and environmental protection. One of the possible applications is the sorption of heavy metals. For the raw halloysite the sorption exclusively takes place on the particles surface. The interlayer space of the mineral is not accessible for cations. Thus the research goal was to provide the access of cations to the interlayer using organic modifications with selected aminoalcohols (Letaief & Detellier 2007). Moreover, the sorption properties of the new material towards selected cations were examined. Dehydrated type of halloysite from Polish deposit Dunino located near Legnica, which is still exploited was used for the experiments. Halloysite-dimethyl sulfoxide (DMSO) complex was used as a precursor. For this purpose 12.5 g of halloysite was reacted with a solution containing 90 mL of DMSO and 10 mL of H2O at room temperature for 7 days. Afterwards the sample was centrifuged and dried at 65°C for 24 h (HDMSO sample). In the next step, the HDMSO was reacted with diethanolamine (DEOA) or triethanolamine (TEOA) at 180°C under argon for 24 h. Finally, it was washed with isopropanol (HTEOA-I sample) and subsequently with water (HTEOA-W sample). The samples were examined by X-ray diffraction (XRD), infrared spectroscopy (IR) and CHNS elemental analysis. The XRD diffraction patterns of HDMSO with D001=11.3 A confirmed the intercalation of halloysite with DMSO. The D001 peaks for the HTEOA-I and HTEOA-W samples were found at 11.3 A and 10.8 A, respectively. In turn, the dml peaks for the HDEOA-I and HDEOA-W were found at 11.3 A and 10.8 A, respectively. The dml decrease after water washing was due to removal of the DMSO remnants and intercalated however not grafted aminoalcohol molecules from the interlayer space. The difference between the d001 values for the HDEOA-W and HTEOA-W results from the size of the organic molecules. The IR bands related to hydrogen bonds between DMSO and kaolinite OH groups were observed at 3539 cm-1 and 3504 cm-1. The formation of HDEOA and HTEOA was confirmed by the disappearance of peaks characteristic for the HDMSO and the presence of C-H stretching vibrations in the 3000-2800 cm-1 region. As the structure of the obtained materials was resistant to water washing they can be named as grafted compounds (Letaief & Detellier 2007, Matusik et al. 2012). The CHNS analysis allowed to calculate the theoretical sorption capacity of the materials (HDEOA: 264 mmol/kg, HTEOA: 355 mmol/kg) assuming that the center, which attracts cations was connected with nitrogen electron pair of aminoalcohols. The materials were tested towards lead sorption. The equilibrium experiments were carried out in the Pb concentration range 0.005-5.0 mmol/L at pH 5. The materials were shaken in Pb solutions (20 g/L ratio) for 24 hours at room temperature. The concentration of Pb was measured using atomic absorption spectroscopy method (AAS). Sorption of Pb on unmodified halloysite reached ~37 mmol/kg for its highest concentration and is relatively high as for the minerals from kaolinite group. However, the sorption for the halloysite modified with aminoalcohols is significantly higher. It was equal to ~57 mmol/kg for the HTEOA and ~62 mmol/kg for the HDEOA. It seems that the structure of molecules determines the sorption capacity. The TEOA has three alkyl chains linked to the nitrogen and the DEOA has two chains. This may cause reduced availability of nitrogen for cations due to steric effects. Therefore, the HDEOA complex achieves higher sorption values. The pH after sorption on the modified halloysite increases rapidly in contrast to raw halloysite which is probably due to adsorption of protons to nitrogen and their competition with lead. This affects the sorption capacity and will be the subject of further study.

17

Aqueous cadmium removal by hydroxylapatite and fluoroapatite

Matusik J., Bajda T., Manecki M.

Geology, Geophysics and Environment

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2012

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Vol. 38, no. 4

427--438

EN

Reducing the bioavailability of toxic heavy metals in groundwaters and urban soils by phosphate addition is an effective technique described in the literature. It is based on the reaction between metal ions and phosphates and results in the precipitation of metal substituted phosphate phases. The formed phosphates are highly insoluble and thermodynamically stable over almost entire pH and Eh range. In the presented study the efficiency and mechanism of cadmium uptake by synthetic hydroxylapatite and natural fluoroapatite was examined within the pH range of 3-7 for different reaction times (2—1440 hours). The solids after reactions were characterized by XRD and SEM-EDS. Percentage reduction of cadmium concentration in the experiments with fluoroapatite and hydroxylapatite, regardless of pH, did not exceed 17% and 25%, respectively. Cadmium uptake from the solution mainly resulted from the formation of cadmium phosphates and/or Ca-Cd phosphate solid solutions on the apatites surface. The release rate of phosphate ions by hydroxylapatite was relatively high. This promoted crystallization of a large number of small crystals. In turn dissolution of fluoroapatite was slower and thus the formation of large crystals was observed. There was no clear evidence for cadmium-calcium ion-exchange mechanism.

18

Delaminacja i transformacja morfologii minerałów z grupy kaolinitu

Matusik J.

Auxiliary Sciences in Archaeology, Preservation of Relics and Environmental Engineering

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2007

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T. 4 spec. ed. [2]

1-2