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The assay is one of the important methods of wastewater treatment, the key is to apply the appropriate adsorbent. Adsorbents after a period will reach saturation adsorption loss of adsorption properties, and therefore, there is a need regeneration treatment, for repeated use, to reduce the cost of wastewater treatment, to improve the utilization of the adsorbent. In this paper, a method of Pharmacy desorption regeneration understand the absorption and regeneration Experimental study of a novel containing copper granular bentonite composite adsorbent, influences the type of chemicals, agent concentration, time, temperature, amount of adsorbent, loading, pH, and other factors impact, and its The desorption mechanism were discussed. The results show that: (1) sulfuric acid, nitric acid, hydrochloric acid, sodium chloride, sodium hydroxide, sodium citrate and EDTA containing copper bentonite composite adsorbent desorption and regeneration. The desorption rate of copper is increased with increasing the concentration of the desorbent, but the magnitude of increase is not large. Bentonite composite adsorbent regeneration rate is consistent with the the desorbent concentration changes with the desorption rate. (2) agent concentration, desorption time, amount of adsorbent, loading, desorption temperature, pH containing copper bentonite composite adsorbent desorption and regeneration have a certain impact. Wherein the relatively large influence is a desorption time and pH, and a relatively small impact is the desorption temperature. (3) in the test medicament for copper desorption effect EDTA Preferably, nitric acid, followed by sodium chloride poor. The regenerative effect EDTA> sodium chloride> nitrate. (4) with a quasi-order kinetics equation, the quasi-second-order equation, Elovich equation, two-constant equation can fit nitrate, sodium chloride, EDTA copper desorption kinetics data, including quasi-first-order kinetics equation and the quasi-second-order equation significant degree of fit best. (5) nitric acid and EDTA the copper desorption process in line with the Langmuir isotherm, while sodium chloride copper desorption process in line with the Langmuir isotherm, Freundlich isotherm and the Temkin isotherms. Nitrate and EDTA the copper desorption is a spontaneous process, while sodium chloride is not. (6) before and after adsorption and desorption bentonite composite adsorbent for X-ray diffraction analysis showed that the adsorption of bentonite composite adsorbent Cu 2 crystal layer between adsorption may exist, nitric acid, sodium chloride , EDTA desorption contained copper bentonite composite adsorbent.
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