http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Ralte Malsawmdawngzela,Sarikokba,Thanhmingliana,Diwakar Tiwari,Seung Mok Lee 대한환경공학회 2022 Environmental Engineering Research Vol.27 No.6
The present study aims to investigate the insights of Alizarin Yellow removal by hybrid materials precursor to natural bentonite. The hybrid materials employed are bentonite modified with hexadecyltrimethylammonium bromide (HDTMA) (BnH) and aluminium pillared HDTMA bentonite (BnAH). Surface morphology of materials are obtained with scanning electron microscopy-Energy dispersive X-ray analysis (SEM-EDX). The batch reactor operations conducted in the removal of Alizarin Yellow by these solids for various parametric studies which enabled to deduce the mechanism involved at solid/solution interface. Sorption capacity and selectivity was increased significantly using hybrid materials in the removal of AY. Hybrid materials showed very high removal capacity of AY and apparently unaffected at varied pH (4.0−10.0) and sorptive concentrations 1.0 to 25.0 mgL<SUP>-1</SUP>. Kinetic studies indicated that an apparent equilibrium occurred within 5–10 min of contact and the kinetic data was better fitted to the pseudo-second-order kinetic model. The percent removal of AY was not affected by increasing the background electrolyte (NaCl) concentration to 0.1 molL<SUP>-1 </SUP>and in presence of several co-existing ions. It is revealed that the hybrid materials are found more organophilic and AY molecule bound with strong forces at the surface of hybrid materials.
Ralte Malsawmdawngzela,Lalhmunsiama,Diwakar Tiwari 대한환경공학회 2022 Environmental Engineering Research Vol.27 No.6
The aim of this study was to synthesize novel and highly efficient functionalized material (BNMPTS) for selective elimination of Cu<SUP>2+</SUP> and Cd<SUP>2+</SUP> from aqueous waste. The detailed insights of solid/solution interactions were investigated by X-Ray photoelectron spectroscopic analyses. The grafting of silane caused for significant decrease in specific surface area of bentonite from 41.14 to 4.65 ㎡/g. The functionalized material possessed significantly high sorption capacity (12.59 mg/g for Cu<SUP>2+</SUP> and 13.19 mg/g for Cd<SUP>2+</SUP>) and selectivity for these cations. The material showed very high elimination efficiency at a wide range of pH ~2.0 to 7.0 for Cu<SUP>2+</SUP>, ~3.0 to 10.0 for Cd<SUP>2+</SUP> and concentration (1.0 to 25.0 mg/L) for Cu<SUP>2+</SUP> and Cd<SUP>2+</SUP>. A rapid uptake of these two cations achieved an apparent equilibrium within 60 minutes of contact. The increased level of background electrolyte concentrations (0.0001 to 0.1 mol/L) did not affect the elimination efficiency of these two cations by BNMPTS. Moreover, the common coexisting ions did not inhibit the removal of these toxic ions. Furthermore, high breakthrough volumes i.e., 1.4 and 3.69 L for <SUP>Cu2+, </SUP>2.6 and 6.64 L for Cd<SUP>2+</SUP> was obtained using 0.25 and 0.50 g of BNMPTS respectively in a fixed-bed column operations.
Ralte Malsawmdawngzela,Diwakar Tiwari 한국화학공학회 2022 Korean Journal of Chemical Engineering Vol.39 No.3
Endocrine disrupting chemicals (EDCs) are emerging water contaminants and efficient elimination is a greater challenge for environmental engineers. The present communication is intended to synthesize the novel dense nanocomposite materials precursors to the bentonite and 3-mercaptopropyletrimethoxy silane/or 3-aminopropyletriethoxy silane. The materials are highly dense, hence the surface area is significantly reduced compared to the pristine bentonite. Further, the materials are intended to be utilized in the elimination of one of the important EDC 17α- ethinylestradiol (EE2). The sorption mechanism is greatly demonstrated based on various parametric studies. It is shown that grafted silane with bentonite network provides enhanced hydrophobicity with organophilic nature and greatly favors the uptake of EE2 at a wide range of pH (5.0-10.0). Relatively rapid uptake of EE2 by the nanocomposite solids followed by a pseudo-second-order kinetic model indicated that the materials are highly efficient for elimination of EE2. Increasing the concentration of EE2 (1.0 to 10.0 mgL-1 ) favored the extent of removal of EE2 and followed the Langmuir adsorption isotherm. Further, the increase in background electrolytes by 1,000 times did not affect the removal of EE2 by these nanocomposites, indicating the sorbing species are attracted with relatively stronger forces. Moreover, the simultaneous presence of several co-ions did not affect the percentage elimination of EE2; this, perhaps, shows an enhanced selectivity of materials towards the 17α-ethinylestradiol. A high loading capacity of EE2 is achieved under column reactor operation using these nanocomposites. Additionally, the materials are promising in the real matrix treatment.
Lalhmunsiama, Lalhmunsiama,Malsawmdawngzela, Ralte,Vanlalhmingmawia, Chhakchhuak,Tiwari, Diwakar,Yoon, Yiyong The Korean Society of Industrial and Engineering C 2022 공업화학 Vol.33 No.5
Clay minerals are natural materials that show widespread applications in various branches of science, including environmental sciences, in particular the remediation of water contaminated with various water pollutants. Modified clays and minerals have attracted the attention of researchers in the recent past since the modified materials are seemingly more useful and efficient for removing emerging water contaminants. Therefore, modified engineered materials having multi-functionalities have received greater interest from researchers. The advanced clay-based materials are highly effective in the remediation of water contaminated with organic and inorganic contaminants, and these materials show enhanced selectivity towards the specific pollutants. The review inherently discusses various methods employed in the modification of clays and addresses the challenges in synthesizing the advanced engineered materials precursor to natural clay minerals. The changes in physical and chemical properties, as investigated by various characterization techniques before and after the modifications, are broadly explained. Further, the implications of these materials for the decontamination of waterbodies as contaminated with potential water pollutants are extensively discussed. Additionally, the insights involved in the removal of organic and inorganic pollutants are discussed in the review. Furthermore, the future perspectives and specific challenges in the scaling up of the treatment methods in technology development are included in this communication.
활성화 벤토나이트를 이용한 수용액으로부터 세슘 흡착 제거
김재규,김무늬,Ralte Malsawmdawngzela,안찬수,이승목 한국수처리학회 2019 한국수처리학회지 Vol.27 No.2
Various treatment methods have been applied to remove cesium in aqueous solution, and adsorption using clay minerals has also been widely used. Bentonite has been highly evaluated as an adsorbent material for the purification of radioactive materials. In this study, bentonite was used for cesium removal, and bentonite was activated by acid to improve cesium removal efficiency. To investigate the adsorption characteristics of cesium by using activated bentonite, pH, initial cesium concentration, time, background electrolyte and interference ion experiment. As a result of pH test, it was found that activated bentonite was more effective for cesium removal than bentonite at pH 4 or higher. The maximum amount of cesium adsorbed by the activated bentonite was 12.8 mg/g, followed by Langmuir adsorption isotherm and pseudo second order model. The adsorption of Cs on the background electrolyte appeared to be a non - specific adsorption affected by the background electrolyte. The anions did not affect cesium adsorption, but the cations were affected by Cs adsorption due to competitive adsorption.