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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.
3
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.
6
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.
7
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.
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.
9
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.
10
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.
EN
The main aim of this work was to prepare the mineral-carbon adsorbents from fly ash. The investigations of spherical oil agglomeration method have been conducted using fly ash from brown coal (lignite) burning ,,Elektrownia Turów" power-plant (Poland). The spherical oil agglomeration method was used in order to obtain the composite adsorbents. The main effort was devoted to the optimal conditions determination for the spherical agglomeration process. The proposed procedure gives a possibility for the preparation of low-costs and effective mineral-carbon adsorbents.
13
EN
Settling process is used to separate solid particles from water suspension. Many factors, like the presence of chemical compounds, affect this process. In this paper, the effect of surfactants addition on the settling velocity of magnesite solid waste was investigated. The studies were conducted in the presence of a natural surfactant (rhamnolipid from Jeneil Biosurfactant Co), cell culture filtrate of Pseudonwnas aeruginosa, and a chemical surfactant (sodium dodecyi sulphate (SDS)). The addition of these compounds caused destabilization of the investigated suspension. A particle size increase and rapid sedimentation were observed. It was noted that the addition of biosurfactant caused a faster settling velocity in comparison to the SDS addition.
PL
Proces kolektywnej (gromadnej) sedymentacji został wykorzystany do badania wpływu surfaktantu i biosurfaktantu na stopień agregacji drobnych ziaren odpadów magnezytowych. W badaniach został użyty płyn po hodowli mikroorganizmu Pseiidomonas aeruginosa oraz odczynnik dostarczony przez firmę Jeneił Biosurfactant Company JBR599. Oba produkty zawierają ramnolipid, będący biosurfaktantem. Dla porównania, część prac przeprowadzono z syntetycznym surfaktantem (dodecylosiarczan sodu - SDS). Badania przeprowadzono używając wodnej zawiesiny odpadów magnezytowych (frakcja -45 pm). Doświadczenia sedymentacyjne były przeprowadzone w szklanych cylindrach sedymentacyjnych, przy użyciu których określano prędkość przesuwania granicy supernatant/zawiesina. Do badania struktury przestrzennej osadu użyto metody ssania kapilarnego (CST). Otrzymane wyniki świadczą, że dodanie biosurfaktantu powodowało przyspieszenie sedymentacji i wzrost wysokości osadu. Ustalono, że małe wartości czasu ssania kapilarnego były odwrotnie proporcjonalne do ilości dodanego surfaktantu.
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