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1

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.

2

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.

3

Wpływ dodatku trehalozy na jakość bułek pszennych otrzymanych w wyniku odroczonego wypieku

Korzeniowska-Ginter R., Naczk-Łukowska A., Maziarz P.

Zeszyty Naukowe Akademii Morskiej w Gdyni

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2016

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nr 93

121--128

PL

Celem pracy była ocena wpływu dodatku trehalozy do ciasta pszennego na jakość bułek otrzymanych metodą odroczonego wypieku. Ciasto sporządzano metodą dwufazową, stosując dodatek trehalozy w ilości 0,5 i 1% w stosunku do mąki. Bułki podpiekano do białej skórki i zamrażano. Po 14 dniach przechowywania półprodukt rozmrażano i wypiekano ostatecznie. W gotowym wyrobie oceniano masę po wypieczeniu i po schłodzeniu oraz objętość 100 g. Przeprowadzono ocenę sensoryczną według skali pięciopunktowej. Oznaczono wilgotność, kwasowość i porowatość miękiszu. Otrzymane bułki charakteryzowały się dobrą jakością. Dodatek trehalozy istotnie wpłynął na kształt i wygląd zewnętrzny oraz elastyczność miękiszu, jak również na masę bułek gorących i wychłodzonych otrzymanych w wyniku odroczonego wypieku. Nie stwierdzono istotnego statystycznie wpływu dodatku trehalozy na wilgotność, porowatość i kwasowość bułek.

EN

The aim of this study was to examine the influence of trehalose addition to the wheat dough on the quality of rolls, obtained by postponed baking method. Dough was prepared by using a two-phases method. Addition of trehalose was 0,5 and 1% by a ratio of flour. Bread rolls were baked to the white colour of crust, cooled and frozen. After two weeks of intermediate storage they were thawed and final rebaked. In final product were estimated weight after baking and after cooling as well as the volume of 100g. Sensory evaluation was carried out using a five-point scale. There were assessed also moisture, acidity and porosity of the crumb. The rolls were of the good quality. The addition of trehalose significantly affected on the shape and appearance and elasticity of the crumb as well as weight of hot and cooled final-baked rolls. There was no statistically significant effect of trehalose addition to humidity, porosity and acidity of rolls.

4

The influence of alkali concentration and temperature on chemical activation of halloysite

Maziarz P.

Geology, Geophysics and Environment

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2016

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Vol. 42, no. 1

97--98

EN

The influence of alkali activation on clay minerals is not thoroughly investigated, particularly in terms of its impact on adsorption possibilities of clay minerals. One of the studied applications of base treated clay minerals was to control sustained drug release (Wang et al. 2013). Based on the recent studies, the base treatment can cause changes in structure, texture, and morphology of clay minerals. These changes are related to partial dissolution of layered structure and subsequent release of Si and Al to the solution (White et al. 2012, Yuan et al. 2015). This modification can be especially promising in case of halloysite, which is a clay mineral revealing unique nanoscale tubular morphology. Previous studies indicate that selective dissolution of halloysite’s aluminosilicate layers can lead to opening of the tubes interior (lumen) (Wang et al. 2013). This type of structural alteration can influence utilization possibilities of halloysite. Therefore, the aim of this work is to investigate the influence of alkali concentration and reaction temperature on the halloysite structure. The halloysite used in the studies came from Polish deposit located in Dunino, near Legnica (SW Poland) which is constantly exploited. The base activation was carried out using sodium hydroxide (NaOH). Firstly, the effect of NaOH concentration on activation efficiency was investigated. The experiments were carried out for the concentration range from 0.01 to 5.0 mol/L at room temperature. Additionally, for the 1.0 mol/L concentration the experiments were performed at temperatures of 50°C, 60°C, 70°C, 80°C and 90°C. the suspensions consisting of 2 g of halloysite and 50 mL of appropriate solution were mixed for 24 h using magnetic stirrer. Subsequently, the samples were washed with water and dried at 60°C. The prepared materials were characterized using XRD and FTIR methods. The IR results revealed that the concentrations of NaOH below 5 mol/L at room temperature did not cause significant changes in spectra of the tested samples. However, the results of experiments carried out in the temperature range from 60°C to 90°C showed that the temperature of the suspension can significantly affect the alkali activation. Based on the IR spectra the reaction at 50°C did not alter the structure of halloysite, in contrast to 60°C, 70°C, 80°C and 90°C temperatures. The changes of relative intensities of the bands associated with inner surface hydroxyls were observed in the 3700–3600 cm −1 region. These results suggest a gradual removal of inner surface hydroxyls, with the temperature increase. The results also indicated a gradual increase of intensity and broadening of the band with the maximum at 3430 cm −1 and 1647 cm −1 which were attributed to H–O–H stretching and bending vibrations of adsorbed water, respectively. It can be also observed that base treatment at higher temperature also caused structural changes within the aluminosilicate framework of halloysite. The frequency shift and broadening of bands assigned to Si-O-Si stretching (1033 cm −1 , 1008 cm −1 ) and bending (54 0 cm −1 ) vibrations were observed. The perturbations and/or removal of Al-O-H was confirmed by the decrease of bands intensity assigned to bending vibrations at 936 cm −1 and 914 cm −1 The higher temperatures resulted in an appearance of new bands at 1470 cm −1 and 1400 cm −1 associated with carbonates. These bands become more evident with the increase in temperature. The XRD results indicated the formation of additional crystalline phases: sodium aluminum silicate, hydrated sodium carbonates and sodium aluminum carbonate silicate. The presence of carbonates in the samples was confirmed also by FTIR spectra. It was suspected that the presence of carbonate may be related to uptake of atmospheric CO 2 and its reaction with NaOH in accordance with earlier reports by Slaty et al. (2013) and Aldabsheh et al. (2015). The results of this work suggest that different variations of the activation conditions should be examined, to find the optimal temperature for alkaline treatment that leads to an increase in the lumen diameter of halloysite, but does not affect the mineral morphology.

5

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).

6

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.

7

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.

8

Zwarcia łukowe wewnątrz rozdzielnic i stacji transformatorowych. Problem nadal groźny

Maziarz P., Szynol J.

Energetyka

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2001

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nr 1

39-41