【摘要】 本文采用不溶性甘蔗渣黄原酸酯脱除废水中的铬(Ⅵ),在pH 2—3的条件下,Cr(Ⅵ)还原成Cr(Ⅲ),Cr(Ⅲ)在pH 8—9时沉淀,废水经处理后,Cr(Ⅵ)的残留浓度达到国家排放标准。更多还原

【Abstract】 Water-insoluble bagasse xanthates (IBX) were prepared by xan-thation of alkalified celluloses which were obtained by treating bagasse with alkali. The precipitation of chromium with IBX was investigated. The process was studied in terms of pH, contact time xanthate dosage, and storage time of IBX. The results showed that the solutions contatining Cr(Ⅵ)must be adjusted to the pH range of 2 to 3,so that Cr(Ⅵ) is reduced to Cr( Ⅲ ),Cr (Ⅲ) is then precipitated at the pH range of 8 to 9 in order to obtain high removal.The observed high removal of chromium was always obtained within 30 min. The optimum chromium/xanthate molar ratio is not in accordance with stoichometric expected ratio. Products containing the effective amounts of magnesium ion appeared to have good room-temperature stability. The concentration of Cr(Ⅵ) in the effluent after treatment is below the industrial wastewater discharge limits.更多还原