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271.
272.
Application of Some Complexing Ion Exchangers for Copper Recovery from Natural Water and Wastewater The rational use of water resources is one of the urgent environmental control problems. These problems can be solved by the treatment of sewage. Removal of different non‐ferrous heavy metal ions from wastewater is of great importance. Besides, the selective complexing ion exchangers are of interest because of their good sorption properties. The present paper is devoted to the study of some complexing resins for copper recovery from natural water and sewage. The following carboxylic resins were studied: the cation exchangers KB‐2T, KB‐4 and the amphoteric ion exchangers ANKB 35, AMF‐2T, and AMF‐2S (manufacturer – “TOKEM” company, Kemerovo, Russia). The exchangers investigated differed from each other both by their functional groups and by their matrix physical structures. The copper recovery from CuCl2‐, CuSO4‐, and Cu(NO3)2‐solutions was studied in batch‐experiments (in presence of NaCl, Na2SO4, and NaNO3). The initial copper concentration in the solutions was 0.0002...0.008 mol/L; pH values were 1.0...5.0. After equilibrium (24 h) the resins were separated from the solution. The copper concentration in the solutions after the sorption was determined by the photometrical method with pyridylazoresorcin (λ = 500 nm). On the basis of the experimental data distribution ratio, the separation factors, equilibrium constants, and stability constants of copper complexes in the exchanger phase were calculated. It was found out in this work that the amphoteric ion exchanger AMF‐2T of macroreticular structure is the most effective for the copper sorption from sewage. 相似文献
273.
A characterization method for AOX in surface water samples was developed and tested. The method involves fractionation using a hydrophobic C18 resin and a weak anionic exchange resin and allows the fractionation of the AOX pool of surface water samples into four fractions: (1) hydrophilic acidic, (2) hydrophilic non‐acidic, (3) hydrophobic acidic, and (4) hydrophobic non‐acidic. The adsorption analysis was verified with AOX‐relevant model compounds and was applied to characterize the AOX pool of a stream sample from the Moskva river (Russia). In addition to the fractionation analysis, size‐exclusion chromatography was used to characterize the AOX pool of the sample studied. Hydrophilic acids made up the major fraction of the AOX pool (55 %). Among this fraction chlorinated high‐molecular acids (humic substances) made up the main fraction (35 %). 相似文献