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EN
This paper reports oil agglomeration of fine metal-bearing shale particles in the presence of cationic (dodecylamine hydrochloride) and anionic (sodium dodecyl sulfate) surfactants and their mixture. The experimental results demonstrated that there was a strong relationship between zeta potential, hydrophobic coagulation, oil agglomeration and particle hydrophobicity in the presence of cationic surfactant, whereas shale neither coagulated nor agglomerated in the presence of anionic surfactant. Addition of either anionic or cationic surfactant in emulsification of a bridging oil increased the size of agglomerates and reduced the concentration of surfactant used in the suspension. The results pointed to synergism between cationic and anionic surfactants in oil agglomeration. Based on the results obtained from this study, the mechanism of oil agglomeration of shale in the presence of ionic surfactants and their mixture was elucidated.
EN
Talc has many applications in various branches of industry. This material is an inert one with a naturally hydrophobic surface. Talc agglomeration is within the wide interest of pharmaceutical industry. Oil agglomeration experiments of talc were carried out to find out and assess the significance of experimental factors. Central composite design (CCD) was used to estimate the importance and interrelation of the agglomeration process parameters. Four experimental factors have been evaluated, i.e. concentration of cationic surfactant and oil, agitation intensity as well as time of the process. The median size of agglomerates (D50) and the polydispersity span (PDI) were used as the process responses. Logarithmic transformations of the responses provide better description of the model, than untransformed responses, with the reduced cubic model for D50 and quadratic model for PDI. This was supported by the Box-Cox plots. It was shown that there were many statistically important factors, including the concentration of cationic surfactant and stirring rate for D50, concentration of oil and stirring rate for PDI, as well as various interactions, up to third order for D50. Optimal conditions for minimum values of reagent amounts as well as mixing time and intensity for the maximum size of agglomerates but of rather narrow size distribution were found.
EN
In this study the role of PEG and PEO-PPO-PEO block copolymers molecular weight in precipitation of calcium carbonate was examined. The CaCO3 particles were characterized by FTIR spectroscopy, X-ray, SEM and particle size distribution analysis. In absence and presence of modifiers, mixing of the reagents led to the formation of calcite crystals. The calcium carbonate obtained with poly(ethylene glycol) and block copolymers was characterized by smaller diameter in comparison with the one without modifiers. It was observed that using compounds with different molecular weights has no obvious effect on the form and properties of precipitated calcium carbonate particles.
EN
The objective of the present study is to assess the efficiency of fly ash and fly ash agglomerates to remove arsenic(III) from aqueous solution. The maximum static uptakes were achieved to be 13.5 and 5.7 mgAs(III)/adsorbent for nonagglomerated material and agglomerated one, respectively. Isotherm studies showed good fit with the Langmuir (fly ash) and the Freundlich (fly ash agglomerates) isotherm models. Kinetic studies indicated that the sorption of arsenic on fly ash and its agglomerates follows the pseudo-second-order (PSO) chemisorption model (R2 = 0.999). Thermodynamic parameters revealed an endothermic nature of As(III) adsorption on such adsorbents. The adsorption results confirmed that fly ash and its agglomerates can be used for As(III) removal from aqueous solutions. Fly ash can adsorb more arsenic(III) than agglomerates, which are easier to use, because this material is less dusty and easier to separate from solution.
5
EN
In this study, the adsorption of surfactant onto the magensite rock and the oil agglomeration of this mineral in aqueous suspension were investigated. The various concentration ratios of cationic and anionic surfactant were used. The results were evaluated by the recovery of carbonates in agglomerates. It was found that the process selectivity was highly dependent on the surfactants concentration ratio, pH, and the amount of salt added. The best separation of quartz from magnesite rock was observed at pH 9. The addition of larger quantity of sodium oleate (15.2 mg/gsolid) led to the increase of carbonates content in agglomerates up to 32.4%. However, the largest carbonates recovery was in the presence of 6.0 mg/gsolid of NaOl.
EN
In this study, the role of polymer in precipitation has been examined by studying the effect of poly(ethylene glycol) (PEG) on the formation of calcium carbonate particles. The CaCO3 particles were characterized by several techniques, such as FTIR, XRD, SEM, and particle size distribution analysis. In the absence of polymer, the mixing of reagents in an aqueous solution led to the formation of calcite crystals. Introduction of poly(ethylene glycol) molecules reduced the rate of crystallization process, and the effect was concentration dependent. In the presence of 0.05, 0.1, and 0.5 % of PEG, after 5 minutes of precipitation initiation, vaterite microspheres appeared in the system and which were transformed into calcite crystals after 24 hours. The calcium carbonate obtained with PEG was characterized by smaller sized particles in comparison with the ones without polymer.
EN
The influence of adsorption and co-adsorption of PEO-PPO-PEO triblock copolymers (Pluronics) as well as surfactants on the zeta potential of magnesite and dolomite aqueous suspension are addressed here. Four Pluronics of various molecular weight were used in these studies. They have been mixed with cationic (CTAB) or anionic (SDS) surfactants. The adsorption isotherms of copolymers and copolymer-surfactant mixture onto magnesite and dolomite have been determined. The adsorbed amount of Pluronics increases with the increasing concentration and reaches plateau. An increase in the adsorbed amounts of both cationic and anionic surfactants onto the mineral surfaces (magnesite and dolomite) has been observed in the presence of Pluronic copolymers. A positive nature of zeta potential was observed in the presence of cationic surfactant, except magnesite without or with a low CTAB concentration. However, an attendant copolymer causes a decrease of zeta potential due to the deformation of an electrical double layer, comparing the presence of an individual cationic surfactant. The adsorbed non-ionic Pluronic layer partially screens the surface charge of mineral particles, and thus, reduces the zeta potential. On the other hand, the adsorption of anionic surfactant and copolymer caused a decrease in the negative value of the zeta potential of both investigated minerals due to increased SDS adsorption. The viscosity measurements were also performed to determine the thickness of adsorbed layer.
8
Content available remote Sorption properties of fly ash from brown coal burning towards arsenic removal
EN
In the present work, the sorptive capacity of fly ash from the combustion of brown coal in relation to arsenic(III) removal from the standard solution as well as the potential application of fly ash in actual wastewater purification have been evaluated.
PL
W tym artykule zbadano pojemność sorpcyjną popiołów lotnych powstających podczas spalania węgla brunatnego w stosunku do arsenu(III) usuwanego z roztworu standardowego oraz zbadano możliwość zastosowania popiołów w oczyszczaniu ścieku rzeczywistego.
9
Content available remote Bioinspired synthesis of calcium carbonate colloid particles
EN
Biomimetic procedure for nucleation and growth of CaCO3 has been presented. The wet chemical syntheses of CaCO3 colloidal particles have been carried out. The characterization of precipitated particles of CaCO3 has been done using the particle size distribution analysis. The effect of physical and chemical parameters on the size of precipitated particles of CaCO3 has been investigated. This research may provide new insight into the precipitation of calcium carbonate.
PL
Zaprezentowano biomimetyczną procedurę zarodkowania wzrostu CaCO3 przeprowadzając chemiczna syntezę „na mokro” koloidalnych cząstek CaCO3. Dokonano charakterystyki wytrąconych cząstek przez wyznaczenie ich składu ziarnowy. Badano też fizyczne i chemiczne parametry wytrąconych ziarn CaCO3. Badania te mogą dostarczyć nowego spojrzenia na precypitację węglanu wapnia.
10
Content available remote Właściwości sorpcyjne popiołów ze spalania węgla
PL
Celem niniejszej pracy było zbadanie zdolności sorpcyjnych popiołu po spalaniu węgla brunatnego pod kątem adsorpcji arsenu (III). Uzyskane wyniki wskazują na znaczną pojemność sorpcyjną popiołu lotnego względem As(III) (33 mg/g), porównywalną do otrzymywanej na żywicach jonowymiennych. Dane doświadczalne dobrze opisuje izoterma Langmuira, a proces adsorpcji kontrolowany jest reakcją chemiczną pseudo drugiego rzędu (model PSO).
EN
The aim of work was to examine sorption of As(III) species, using fly ash from lignite burning. The results obtained show that the sorption capacity of fly ash (33 mg/g) is comparable to commercial sorbent. Experimental data can be described by means ofLangmuir isotherm. Adsorption process obeys the pseudo-second order (PSO) kinetics.
11
PL
Ciecze jonowe posiadają potencjalne zastosowanie w technikach separacyjnych. W niniejszej pracy badano zdolność heksafluorofosforanu 1-butylo-3-metyloimidazoliowego [BMIM][PF6] do rozdziału wodnych mieszanin metanolu, etanolu i propanolu. Eksperymentalnie uzyskano dane dla równowag ciecz-ciecz dla układów [BM1M][PF6] - alkohol - woda w temperaturze 298,15 K. Dane doświadczalne zostały w satysfakcjonujący sposób skorelowane za pomocą modelu NRTL.
EN
Ionic liquids have potential usability in separation techniques. In this work, ability of l-buthyl-3-methylimidazolium hexafluorophosphate [BMIM] [PFJ to separate methanol, ethanol and propanol from water was investigated. Liquid - liquid equilibrium data for [BMIM][PF6] - alcohol - water systems were measured at 298.15 K. The phase equilibrium data were satisfactorily correlated using the non-random two-liquid (NRTL) model.
PL
Obecność odpadów przemysłowych w środowisku naturalnym staje się coraz bardziej zauważalnym problemem w ochronie środowiska. Za główne źródło ich powstawania, uważa się przemysł wydobywczy i przetwórstwa kopalin. W wyniku prowadzenia procesów wzbogacania, bądź procesów hutniczych, powstają odpady deponowane na hałdach, które w znaczący sposób przyczyniają się do zanieczyszczeń wód gruntowych. Dzieje się tak w wyniku transportu trudno rozpuszczalnych zanieczyszczeń przez naturalny polimineralny ośrodek porowaty. Zjawisko to zostało zaliczone do głównych procesów mających istotny wpływ na zanieczyszczanie wód gruntowych.
EN
The storage of insecure industrial waste, descended from mining and metallurgical industry, has an influence on the pollution of a ground and groundwater. It is a result of migration of toxic substances into the bed of soli. The weathering processes and hydrodynamic changes in soil causes the colloidal particles formation, which are effective contaminations carriers through mineral porous media. In this paper transport of colloidal particles: synthetic hematite and natural kaolin has been investigated. The porous medias were waste from both Szklary and Złoty Stok heaps. The aim of this work is to inspect the influence of arsenate ions on the behaviour of colloidal particles in porous bed. The investigations were conducted in two ionic strengths: 5ź10-3 M KCl and 5ź10-4 M KCl, at pH 9.2-11.6. Results showed that transport of colloidal hematite was facilitated, when arsenic ions were adsorbed onto the colloid particles. Additionally, the increase of mobility of hematite was caused by a decrease of ionic strength. In the case of kaolin transport, the results showed an increase of kaolin particles migration without arsenic ions. These behaviour of colloidal kaolin particles into mineral bed isexplained by different surface property of kaolin particles. Results of examinations on colloidal particles of hematite and kaolin transport through column with mineral bed show, that examined mobility is conditioned with physico-chemical proprieties of colloidal particles and materials of porous bed. Studied colloids, can influence pollution of underground waters in the areas of storing of studied industrial wastes. Results of conducted measurements show, that the process of examined colloidal particles transport is influenced by presence of adsorbed arsenic ions. It is the most perceptible phenomenon in the case of the colloidal hematite, particularly for porous medium built from materials taken from the southern side of heap in Szklary and heap in Złot Stok. Additionally, influence of ion strength on quantity of transported colloidal particles through the layer of porous mineral medium was observed. When ion strength was decreasing, the thickness of the double electric layer increases on colloidal particles. It has impact on decrease of attracting interactions among particles of colloid, and also between colloidal particle and grain of mineral bed. The opposite case was noted during investigations on transportation of colloidal particles of kaolin. Adsorption of arsenic ions by particles of kaolin causes decrease of their mobility. This causes stopping of migration of arsenic ions to underground waters. The similar result is obtained when ion strength is enlarged.
13
Content available remote Transport of ions in quartz sand
PL
Migracja jonów metali przez porowatym ośrodku, utworzony z ziaren mineralnych, ma istotne znaczenie w takich procesach jak ługowanie i bioługowanie oraz w szeregu procesach biogeochemicznych. Transport toksycznych metali w stanowi poważny problem w ochronie środowiska naturalnego i powinien być dokładnie zbadany. W pracy przedstawiono wyniki badań migracji jonów Ni(II), Cr(III) i Pb(II) przez porowaty ośrodek utworzony przez piasek kwarcowy. Doświadczenia zostały przeprowadzone z wykorzystaniem poziomo usytuowanej rury, wypełnionej piskiem kwarcowym. Powierzchnia ziaren kwarcu była modyfikowana przez działanie kationowego (CTAB) i anionowego surfaktantu. Efektywność migracji jonów przez porowaty ośrodek mineralny była kontrolowana przez analizę profilu stężeń kationu w złożu. Adsorpcja kationowego surfaktantu sprzyja adsorpcji jonów do ziaren kwarcu. Odwrotnie, obecność anionowego surfaktantu sprzyja migracji jonów. Obecność CTAB w badanym złożu kwarcowym powodowała wzrost adsorpcji adsorpcji jonów metali na powierzchni złoża. Obecność SDS spowodowała wzrost mobilności metali bardziej niż wzrost prędkości przepływu wody i znacząco zmniejszyła adsorpcję jonów na powierzchni piasku. Anionowe surfaktanty są szeroko stosowane do odzysku oleju, przede wszystkim dzięki ich małej tendencji do adsorbowania, stabilności w wysokiej temperaturze i ciśnieniu i niskich kosztach [11]. Badania sugerują, że te surfaktanty mogą być użyteczne w usuwaniu metali. Mobilność badanych metali w piasku kwarcowym wzrasta w kolejności: Ni (II) > Cr (III) > Pb (II) i wpływa na nią obecność anionowych surfaktantów i wzrost przepływu wody
EN
Flotation tailings, obtained from the copper recovery process, were converted into aggregates by means of the spherical oil agglomeration process, using sodium oleate or dodecylammonium hydrochloride as particles’ surface modifiers, and kerosene as bridging oil. The agglomeration process was characterized in respect to the surfactant nature, its concentration and amount of kerosene used. Resulting agglomerates were carbonized at 700°C in the Grey-King retort to give the mineral-carbon adsorbent. Subsequent alkaline work-up resulted in substantial increase of sorptive properties, as determined by the adsorption of water vapour, benzene and methanol and BET surface measurement. Simultaneously, removal of As3+ ions from aqueous solution has been examined. The results obtained in the present study clearly indicate possibility of making cheap and valuable composite sorbents from flotation tailings.
EN
Extraction of several chloro compounds from water has been examined. As the extracting liquid the 1-butyl-3-methylimidazolium hexafluorophosphate [BMIM][PF6], which is common hydrophobic ionic liquid, was used. Additionally, extraction of selected chlorinated compounds from tert-butylmethylether (MTBE) was investigated. The obtained results show the usefulness of [BMIM][PF6] to remove the organic impurities from water, particularly at the concentration range inappropriate for biological purification plants.
16
Content available remote The effect of protein surfactant interaction on magnesite rock flotation
EN
For many years, interaction of proteins with surfactants in solution has been a subject of extensive studies. The addition of surfactants and proteins to solution leads to the formation of protein surfactant complex. The structure of these objects depends on many factors, e.g. the reagent concentrations, the type of chemical compounds used, the order of protein and surfactant addition. The aim of this work was to examine the way of adsorption of protein (chicken egg albumin) and surfactant (sodium dodecyl sulphate) on the mineral surface (magnesite rock) affects the properties of magnesite suspensions. The effect of these interactions on the flotation of magnesite has been investigated. Effeciency of flotation (yield and separation of magnesite from quartz) was higher when both SDS and albumin were adsorbed at the particle surface.
PL
Od wielu lat prowadzone są badania nad wzajemnym oddziaływaniem cząstek białka i surfaktantu. Efektem tego oddziaływania jest powstanie kompleksu białko-surfaktant. Celem pracy było sprawdzenie, w jaki sposób kompleks białko-surfaktant, powstały na powierzchni ciał stałego, wpływa na właściwości powierzchniowe ciał stałych. W badaniach użyto, jako białka albuminy a jako surfaktantu SDS. Badania były prowadzone na skale magnezytowej z kopalni Wiry. Badano adsorpcję odczynników na powierzchni ciała stałego i flotację. Otrzymane wyniki częściowo wyjaśniają problem oraz stanowią asumpt do dalszych badań nad separacją magnezytu od krzemionki.
17
Content available remote Synthesis of silver nanoparticles using microorganisms
EN
Biosynthesis of silver nanoparticles using Penicillium fungi has been reported. The extracellular mechanism of silver nanoparticles creation was investigated by UV-Vis spectroscopy, electron microscopy and laser diffraction. The zeta potential of silver nanoparticles has also been determined.
18
Content available remote Oil agglomeration of mineral tailings in mixed-surfactant systems
EN
In this paper the results of spherical oil agglomeration of mineral tailings were presented. Tailings from nickel recovery (the Szklary heap, Lower Silesia, Poland) were used in these investigations. Agglomeration experiments have been carried out in water suspension of mineral particles in the presence of cationic and anionic surfactants and kerosene as bridging oil.
PL
W niniejszym artykule przedstawiono wyniki badań procesu aglomeracji olejowej odpadów mineralnych, pozostałych po hutniczej obróbce rudy niklowej, zgromadzonych na hałdzie w okolicach miejscowości Szklary na Dolnym Śląsku. Proces prowadzono w zawiesinie wodnej cząstek mineralnych w obecności surfaktantu kationowego oraz anionowego, użytych jako substancje modyfikujące właściwości powierzchniowe ciała stałego oraz emulgatora oleju (nafty) w wodzie.
EN
The scope of this contribution was to investigate in detail an application of fly ash adsorbent for the removal of arsenite ions from a dilute solution. The experiments have been carried out using fly ash from black coal burning power plant "Siersza" and brown coal burning power plant "Turów" (Poland), which was wetted, then mixed and tumbled in the granulator with a small amount of cement to increase the mechanical strength of agglomerates. The measurements of arsenic adsorption from the aqueous solution were carried out in the flask (with shaking), as well as in the column (with circulation), in order to compare two different methods of contacting waste with adsorbent. The adsorption isotherms of arsenic were determined for granulated material, using the Freundlich model. Kinetics studies indicated that the sorption follows a pseudo-first-order (PFO) model (Lagergren) and the Elovich-type model.
PL
W pracy przedstawiono wyniki badań eksperymentalnych hydrodynamiki i wymiany masy w ekstrakcyjnym układzie octan n-bu-tylu + kwas octowy woda. Badania wykonano w kolumnie z posuwisto- zwretnym ruchem półek sitowych dla kierunku wymiany masy z fazy rozproszonej do fazy ciągłej. Wyróżniono nowy obszar pracy RFC - emulsyjno-agregatowy.
EN
The system of ri-butyl acetate + acetic acid —ť water (with mass transfer from dispersed to continuous phase) in a reciprocating plate column (RFC) was investigated. The experiments with high flow of both phases covered a full useful range of Apf. A new operating range of the RFC called the emulsion-aggregate regime was found.
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