The sedimentation behaviors of bauxite flotation concentrates were investigated at different pH values and floceulant dosages. The effects of three types of flocculants （ cationic, anionic and non-ionic polyacrylamid...The sedimentation behaviors of bauxite flotation concentrates were investigated at different pH values and floceulant dosages. The effects of three types of flocculants （ cationic, anionic and non-ionic polyacrylamide floceulants） as well as the molecular weight of anionic flocculants on the sedimentation of concentrate were studied. It is shown from the experimental results that at the pH 7.0, best sedimentation capability is reached when anionic polyacrylamide flocculant （molecular weight 14 million） is added and the optimal dosage is 30 g/t.展开更多
The paraffin wax microemulsion was prepared from fully refined paraffin wax No.58-60 in the presence of a nonionic surfactant and an anionic surfactant.The influence of manufacturing parameters on the particle diamete...The paraffin wax microemulsion was prepared from fully refined paraffin wax No.58-60 in the presence of a nonionic surfactant and an anionic surfactant.The influence of manufacturing parameters on the particle diameter of paraffin wax microemulsion included the quantity of the emulsifier,the temperature and emulsification time,the stirring speed,the pH value and the auxiliary ingredient(cosurfactant).The test results showed that the temperature of emulsification had little effect on the particle size of paraffin wax microemulsion in a temperature range of 75-85 ℃.Other manufacturing parameters all had a great effect on the particle size of paraffin wax microemulsion.The optimum preparation conditions included:a w(emulsifier) of 6%,an emulsification temperature of 80 ℃,an emulsification time of 40 min,a pH value of about 8,and a stirring speed of 600 r/min,with n-amyl alcohol serving as the co-surfactant.Under these conditions,a translucent and baby blue paraffin wax emulsion was prepared with its particle size equating to 97 nm.展开更多
文摘以正己醇作为引发剂,分别与环氧乙烷和环氧丙烷发生聚合,再以气体三氧化硫进行硫酸化反应,合成了正己醇聚氧乙烯醚硫酸钠(HE3S)以及正己醇聚氧丙烯醚硫酸钠(HP3S)2种阴非离子型表面活性剂。采用FTIR和1H NMR技术对表面活性剂结构进行了表征。通过平衡表面张力、动态表面张力和动态接触角研究了其水溶液的表面活性。实验结果表明,HE3S和HP3S在298 K下的临界胶束浓度分别为58.36 mmol/L和53.84 mmol/L,最低表面张力分别为33.91 m N/m和33.29 m N/m;由动态表面张力计算出的扩散系数,可知两种表面活性剂在水溶液中的吸附机理均属于混合动力控制吸附;当溶液浓度为150 mmol/L时,HE3S和HP3S的水溶液液滴在石蜡膜上可以短时间内快速铺展,其最低接触角分别达到64.5°和55.9°。
基金supported by a grant from the National Key Fundamental Research and Development Program (2005cb6237601)
文摘The sedimentation behaviors of bauxite flotation concentrates were investigated at different pH values and floceulant dosages. The effects of three types of flocculants （ cationic, anionic and non-ionic polyacrylamide floceulants） as well as the molecular weight of anionic flocculants on the sedimentation of concentrate were studied. It is shown from the experimental results that at the pH 7.0, best sedimentation capability is reached when anionic polyacrylamide flocculant （molecular weight 14 million） is added and the optimal dosage is 30 g/t.
基金supported by The National Natural Science Funds (Project No. 21076025)
文摘The paraffin wax microemulsion was prepared from fully refined paraffin wax No.58-60 in the presence of a nonionic surfactant and an anionic surfactant.The influence of manufacturing parameters on the particle diameter of paraffin wax microemulsion included the quantity of the emulsifier,the temperature and emulsification time,the stirring speed,the pH value and the auxiliary ingredient(cosurfactant).The test results showed that the temperature of emulsification had little effect on the particle size of paraffin wax microemulsion in a temperature range of 75-85 ℃.Other manufacturing parameters all had a great effect on the particle size of paraffin wax microemulsion.The optimum preparation conditions included:a w(emulsifier) of 6%,an emulsification temperature of 80 ℃,an emulsification time of 40 min,a pH value of about 8,and a stirring speed of 600 r/min,with n-amyl alcohol serving as the co-surfactant.Under these conditions,a translucent and baby blue paraffin wax emulsion was prepared with its particle size equating to 97 nm.
