研究独居石与捕收剂水杨羟肟酸的作用过程,考察了p H值、药剂浓度、时间等因素对矿物可浮性及水杨羟肟酸离子在矿物表面吸附热力学及动力学的影响。结果表明,独居石在中性和弱碱性条件下上浮率超过90%;水杨羟肟酸离子在独居石表面的吸...研究独居石与捕收剂水杨羟肟酸的作用过程,考察了p H值、药剂浓度、时间等因素对矿物可浮性及水杨羟肟酸离子在矿物表面吸附热力学及动力学的影响。结果表明,独居石在中性和弱碱性条件下上浮率超过90%;水杨羟肟酸离子在独居石表面的吸附符合Langmuir模型,吸附过程吉布斯自由能变化-28.5 k J/mol,理论饱和吸附量为1.94×10^(-5)mol/g,吸附平衡常数为1.11×10~5L/mol。吸附过程平均吸附能19.5 k J/mol,说明水杨羟肟酸离子在独居石表面的吸附为化学吸附,吸附过程符合准二级动力学模型,速率常数5.3×10~4 g/(min·mol),捕收剂离子在矿物界面表膜中的扩散过程是浮选过程的控制步骤。展开更多
Salicylhydroxamic acid(SHA) was covalently bound onto crosslinked polystyrene spheres(CPSs) via the Friedel-Crafts alkylation reaction between chloromethylated CPSs and SHA in the presence of SnCI4 as the Lewis ac...Salicylhydroxamic acid(SHA) was covalently bound onto crosslinked polystyrene spheres(CPSs) via the Friedel-Crafts alkylation reaction between chloromethylated CPSs and SHA in the presence of SnCI4 as the Lewis acid catalyst. The resulted SHA-CPSs possessed very strong chelating ability for heavy metal ions. In particular, the saturated adsorption amount of SHA-CPSs for Cu2+ ions could reach as high as 34.2 mg/g at 318 K. The chelating capability of SHA-CPSs towards heavy metal ions was pH and temperature dependent. SHA-CPSs also showed se- lective metal coordination with the chelating capacity decreasing in the order of Cu2+ 〉Zn2+〉〉Pb2+. The adsorption isotherms conformed well to the Langmuir model, and the adsorption process was found to be entropy-driven and endothermic. Besides, SHA-CPSs possessed the excellent reusability.展开更多
文摘研究独居石与捕收剂水杨羟肟酸的作用过程,考察了p H值、药剂浓度、时间等因素对矿物可浮性及水杨羟肟酸离子在矿物表面吸附热力学及动力学的影响。结果表明,独居石在中性和弱碱性条件下上浮率超过90%;水杨羟肟酸离子在独居石表面的吸附符合Langmuir模型,吸附过程吉布斯自由能变化-28.5 k J/mol,理论饱和吸附量为1.94×10^(-5)mol/g,吸附平衡常数为1.11×10~5L/mol。吸附过程平均吸附能19.5 k J/mol,说明水杨羟肟酸离子在独居石表面的吸附为化学吸附,吸附过程符合准二级动力学模型,速率常数5.3×10~4 g/(min·mol),捕收剂离子在矿物界面表膜中的扩散过程是浮选过程的控制步骤。
基金the National Young Scientists Fund of China(No.21307116), the Natural Science Foundation of Shanxi Province of China(No.2014011017-5), the Project for the Outstanding Innovative Teams of Higher Learning Institutions of Shan- xi Province, China(No.201504) and the Fund Program for the Scientific Activities of Selected Returned Overseas Professionals in Shanxi Province, China(No.20140828).
文摘Salicylhydroxamic acid(SHA) was covalently bound onto crosslinked polystyrene spheres(CPSs) via the Friedel-Crafts alkylation reaction between chloromethylated CPSs and SHA in the presence of SnCI4 as the Lewis acid catalyst. The resulted SHA-CPSs possessed very strong chelating ability for heavy metal ions. In particular, the saturated adsorption amount of SHA-CPSs for Cu2+ ions could reach as high as 34.2 mg/g at 318 K. The chelating capability of SHA-CPSs towards heavy metal ions was pH and temperature dependent. SHA-CPSs also showed se- lective metal coordination with the chelating capacity decreasing in the order of Cu2+ 〉Zn2+〉〉Pb2+. The adsorption isotherms conformed well to the Langmuir model, and the adsorption process was found to be entropy-driven and endothermic. Besides, SHA-CPSs possessed the excellent reusability.