Research of Purifying Alkali Weight-Reduction Wastewater to Recovery of Terephthalic Acid

摘要

In those traditional ways of treating alkali weight-reduction wastewater, the COD removal is greatly considered, while recovering terephthalic acid (TA) by valuable resource according to the principles of sustainable development is less involved. In this research, recovery of high pure TA from alkali weight-reduction has been researched by purified mother liquid with coagulation-sedimentation. The purity of TA obtained was investigated by various methods, results has shown that the characters of TA was great improved in view of high recovery rate by coagulation-sedimentation on conditions of pH 7.0-8.0 of wastewater and 200-250mg/l in quantity of PAC, so coagulation-sedimentation by pretreatment is an effective method. The study is also very useful in recycling of PET or treating TA industrial wastewater.