New Mg-Al Type Sorbent for Efficient Removal of Boron from Waste Water Containing High-concentration of Boron from Pressurized Water Reactor Nuclear Power Plants

A new Mg-Al type layered double hydroxide(LDH) free of CO32- was formed via a specific process consis-ting of the steps of first calcination and subsequent hydrolyzation in water of LDH source material. The resultant Mg-Al LDH can efficiently remove boron from simulated waste water containing high-concentration of boron from pressurized water reactor nuclear power plants. The concentration of boron in the simulated boron-containing waste water was reduced from 2000 mg/L to 10 mg/L by three cycles-relay treatment using the sorbent developed here, which met the requirement that the concentration of boron in the waste water has to be less than 30 mg/L for the construction of new inland nuclear power plants. The maximum sorption capacity of the sorbent developed in this study was as high as 39.64 mg/g at pH of 10.61 and temperature of 20 degrees C. Meanwhile, the structural evolution at molecular level during the calcination and hydrolyzation process was investigated. The influence of parameters such as pH value, initial boron concentration, sorbent dosage, and agitation time on boron removal was also investigated.