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This paper studies the conditions of treatment of high concentration of the solvent extraction process of electroplating wastewater containing chromium ( VI ) , as well as anti - extraction process conditions . In this paper, a literature search , select tetrabutylammonium chloride (TBAC) , tetrabutyl ammonium bromide (TBAB) , tertiary trialkyl with N235 , tri-iso -octylamine ( Toan ) extractant selected kerosene , methyl isobutyl -butyl ketone, n - hexane , chloroform as the diluent. Single factor test designed to examine the initial acidity of extractant concentration , diluent , the aqueous phase , the aqueous phase of the initial concentration of chromium , the oscillation time , extraction temperature , compared to factors such as the impact of the extraction . The results show that : the diluent, the concentration of extraction agent , the water phase the initial acidity , the oscillation time, extraction temperature, etc. affecting the extraction process ; test, select tetrabutylammonium chloride - methyl isobutyl ketone organic phase , taking extractant concentration of 75 %, a water phase pH was 0.5, compared to 1:1, the reaction temperature is room temperature, the process conditions of the oscillation time of 10min , the Cr ( VI ) of the extraction efficiency of 98.6% . In the stripping process , select 4mol / L sodium hydroxide as stripping agent , the use of single-factor experimental design investigated oil alkali ratio , reaction temperature on the back extraction , the results show that : the oil alkali ratio of 1:1 , not only the stripped lye higher concentration of chromium , and the back-extraction rate is also higher ; temperature of certain anti- extraction , the temperature rises back extraction rate decreased slightly , and the back-extraction process is an exothermic process , but modest impact , therefore, the back-extraction choose to operate under ambient conditions . Use the extracted organic phase stripping agent deal with Guangzhou Development Zone, a company electroplating wastewater containing chromium under optimum conditions , the extraction efficiency of 98.5% .
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