Selective separation of silica from a siliceous-calcareous phosphate ore that had been sieved into different size fractions is investigated by a combination of chemical analysis,zeta potential measurement and FTIR and...Selective separation of silica from a siliceous-calcareous phosphate ore that had been sieved into different size fractions is investigated by a combination of chemical analysis,zeta potential measurement and FTIR and XPS techniques.Scrubbing is a better choice than flotation for removing silica from the coarse fractions.The P_2O_5 grade of the coarse fractions is increased to about 30%by scrubbing and the product yields are higher than those obtained by flotation.The silica in the fine fraction is separated by reverse flotation.An alkyl amine salt(DAH)is an effective collector and the P_2O_5 grade of the fine fraction can be increased by 7%to beyond 30%under acidic conditions.The higher zeta potential obtained using DAH suggests that it is more strongly absorbed onto the ore particles than the other cationic collectors. FTIR and XPS results confirm physical absorption of the cationic collector onto the ore surface.They also indicate that calcite is dissolved at low pH values,which increases the Si concentration on the ore surface.展开更多
根据不同地区的生态环境,采用广泛性筛选,用解离目标矿物复筛方法,寻找开发出性能优异的具有良好应用前景的解磷细菌。采用该方法,从贵州铜仁万山钾矿产区分离培育出一株解磷菌株,命名为TK.1。通过细菌生理生化测试,形态学观察,16S r DN...根据不同地区的生态环境,采用广泛性筛选,用解离目标矿物复筛方法,寻找开发出性能优异的具有良好应用前景的解磷细菌。采用该方法,从贵州铜仁万山钾矿产区分离培育出一株解磷菌株,命名为TK.1。通过细菌生理生化测试,形态学观察,16S r DNA同源性分析,NCBI数据库对比分析研究,该菌属于节杆菌属。TK.1菌株与商业菌巨大芽孢杆菌解离煤矸石的对比研究表明:TK.1菌株解磷指标及效果优于巨大芽孢杆菌,是一株性能优异的解磷细菌。新型解磷细菌的开发,使煤矸石有可能成为生产微生物矿物肥料的原料,解决煤矸石污染问题,对环境保护和可持续性发展具有重要意义。展开更多
自燃煤矸石作为吸附剂对水溶液中的磷酸盐有较好的吸附去除作用。通过改变时间、溶液初始浓度和温度等条件,研究了自燃煤矸石对磷酸盐的吸附反应。结果表明,在298 K的条件下,自燃煤矸石对磷的最大饱和吸附量可达7.07mg·g^(-1),吸...自燃煤矸石作为吸附剂对水溶液中的磷酸盐有较好的吸附去除作用。通过改变时间、溶液初始浓度和温度等条件,研究了自燃煤矸石对磷酸盐的吸附反应。结果表明,在298 K的条件下,自燃煤矸石对磷的最大饱和吸附量可达7.07mg·g^(-1),吸附平衡时间约为120 h,而且吸附数据符合Langmuir等温吸附模式。动力学研究数据表示,其吸附过程符合伪二级动力学模式和颗粒内扩散模式,证明了吸附过程中同时发生了化学吸附和物理吸附。吸附热力学参数自由能变ΔG为(-10.52,-11.74,-14.89)k J·mol^(-1),焓变ΔH为46.96 k J·mol^(-1)和活化能E为63.71 k J·mol^(-1),证明了吸附过程属于自发的吸热反应,是属于物理吸附和化学吸附的共同作用。展开更多
基金the National Key Technology R&D Program of China forthe support of this work(No.2007BAE58B01).
文摘Selective separation of silica from a siliceous-calcareous phosphate ore that had been sieved into different size fractions is investigated by a combination of chemical analysis,zeta potential measurement and FTIR and XPS techniques.Scrubbing is a better choice than flotation for removing silica from the coarse fractions.The P_2O_5 grade of the coarse fractions is increased to about 30%by scrubbing and the product yields are higher than those obtained by flotation.The silica in the fine fraction is separated by reverse flotation.An alkyl amine salt(DAH)is an effective collector and the P_2O_5 grade of the fine fraction can be increased by 7%to beyond 30%under acidic conditions.The higher zeta potential obtained using DAH suggests that it is more strongly absorbed onto the ore particles than the other cationic collectors. FTIR and XPS results confirm physical absorption of the cationic collector onto the ore surface.They also indicate that calcite is dissolved at low pH values,which increases the Si concentration on the ore surface.
文摘根据不同地区的生态环境,采用广泛性筛选,用解离目标矿物复筛方法,寻找开发出性能优异的具有良好应用前景的解磷细菌。采用该方法,从贵州铜仁万山钾矿产区分离培育出一株解磷菌株,命名为TK.1。通过细菌生理生化测试,形态学观察,16S r DNA同源性分析,NCBI数据库对比分析研究,该菌属于节杆菌属。TK.1菌株与商业菌巨大芽孢杆菌解离煤矸石的对比研究表明:TK.1菌株解磷指标及效果优于巨大芽孢杆菌,是一株性能优异的解磷细菌。新型解磷细菌的开发,使煤矸石有可能成为生产微生物矿物肥料的原料,解决煤矸石污染问题,对环境保护和可持续性发展具有重要意义。
文摘自燃煤矸石作为吸附剂对水溶液中的磷酸盐有较好的吸附去除作用。通过改变时间、溶液初始浓度和温度等条件,研究了自燃煤矸石对磷酸盐的吸附反应。结果表明,在298 K的条件下,自燃煤矸石对磷的最大饱和吸附量可达7.07mg·g^(-1),吸附平衡时间约为120 h,而且吸附数据符合Langmuir等温吸附模式。动力学研究数据表示,其吸附过程符合伪二级动力学模式和颗粒内扩散模式,证明了吸附过程中同时发生了化学吸附和物理吸附。吸附热力学参数自由能变ΔG为(-10.52,-11.74,-14.89)k J·mol^(-1),焓变ΔH为46.96 k J·mol^(-1)和活化能E为63.71 k J·mol^(-1),证明了吸附过程属于自发的吸热反应,是属于物理吸附和化学吸附的共同作用。
