Synthesis of modified polyacrylamide with high content of hydroxamate groups and settling performance of red mud  

作　　者：刘锦伟 胡慧萍 王梦 陈湘攀 陈启元 丁治英 

机构地区：[1]College of Chemistry and Chemical Engineering, Central South University

出　　处：《Journal of Central South University》2015年第6期2073-2080,共8页中南大学学报（英文版）

基　　金：Project(51174231)supported by the National Natural Science Foundation of China

摘　　要：Hydroxamated polyacrylamide（HPAM） was synthesized from polyacrylamide（PAM） with high relative molecular mass under the optimum reaction conditions（p H 12 and a molar ratio of hydroxylamine to amide groups of 1.5 at 50 ℃for 12 h）. The hydroxamate groups of HPAM were verified by Fourier transform infrared spectrum（FT-IR）. 46%（molar fration） hydroxamate groups and 23%（molar fraction） carbonyl groups on HPAM were determined by conductometric titration combined with Kjeldahl＇s microanalysis method. The settling performance achieved at different flocculant dosages was investigated with high goethite-containing red mud slurry of simulated Bayer process synthesized in laboratory. It turns out that the settling performance of high goethite-containing red mud was better with HPAM. The average settling rate of red mud in the first 5 min and the turbidity of supernatant after settling for 30 min are 2.36 m/h and 507 NTU, respectively, at a flocculant dosage of 120 g/t, which is similar to that achieved with Hx-600.Hydroxamated polyacrylamide(HPAM) was synthesized from polyacrylamide(PAM) with high relative molecular mass under the optimum reaction conditions(p H 12 and a molar ratio of hydroxylamine to amide groups of 1.5 at 50 °C for 12 h). The hydroxamate groups of HPAM were verified by Fourier transform infrared spectrum(FT-IR). 46%(molar fration) hydroxamate groups and 23%(molar fraction) carbonyl groups on HPAM were determined by conductometric titration combined with Kjeldahl's microanalysis method. The settling performance achieved at different flocculant dosages was investigated with high goethite-containing red mud slurry of simulated Bayer process synthesized in laboratory. It turns out that the settling performance of high goethite-containing red mud was better with HPAM. The average settling rate of red mud in the first 5 min and the turbidity of supernatant after settling for 30 min are 2.36 m/h and 507 NTU, respectively, at a flocculant dosage of 120 g/t, which is similar to that achieved with Hx-600.

关 键 词：hydroxamated polyacrylamide symhesis red mud settling performance 

分 类 号：TQ317[化学工程—高聚物工业]