Synthesis of Cationic High Polymeric Flocculants from Starch-Graft-Poly (DMDAAC-co-AM) and Application in Fine Coal Slurry
Based on the characteristic of ultra-fine coal slurry with high ashes, cationic modified starch macromolecule flocculants St-DMDAAC-AM was prepared by grafting dimethyldiallylammonium chloride (DMDAAC) and acrylamide (AM) onto starch. The optimum conditions with respect to initiator variety and concentration, monomer concentration and ratio, polymerization temperature, polymerization time and medium PH have been investigated. The results show that the intrinsic viscosity of St-DMDAAC-AM reached as high as 694 mL/g under the following condition: initiator=0.73 mmol/L, St: DMDAAC: AM=4:3:9, pH=5.7, temperature＝35 ℃, time=3 h. The product was characterized by FTIR, DSC and SEM respectively. Then the flocculation and filtration experiments of fine coal slurry with PAM, St-AM, and St-DMDAAC-AM et al were carried out. The results show that the flocculation of coal slurry with St-DMDAAC-AM was the best because the cationic flocculants can play both roles of the charge neutralization and the formation of particle-polymer-particle bridges, the transmittance of ultra-fine coal slurry with St-DMDAAC-AM can be enhanced 3 times at the dosage of 10 mg/L, and the filtration time of coal slurry with it can be decreased 2/3 at the dosage of 225 mg/L than blank experiment, in which the moisture of filter cake is about 25％. As a result, it can effectively improve the effect of settlement and filtration of ultra-fine coal, increase the efficiency of coal preparation, and provide an effective way for fine coal slurry treatment from environmental protection and application.
modified starch DMDAAC AM St-DMDAAC-AM fine coal slurry
ZHU Shuquan JIANG Linhua ZHANG Huawen
School of Chemistry and Environmental Engineering,China University of Mining and Technology,Beijing 100083,China
国际会议
2009 International Symposium on Environmental Science and Technology(2009环境科学与技术国际会议)
上海
英文
1290-1295
2009-06-02（万方平台首次上网日期，不代表论文的发表时间）