活化蛇纹石促进磷酸改性高岭土对K^+的吸附试验研究  

Enhanced Adsorption Study Test of Potassium Cation Using Kaolinite Modified by Phosphoric Acid with Activation of Antigorite

作　　者：祝雯霞 张其武[2] 李学伟 孔宁 吴李娜 雷治武 ZHU Wenxia;ZHANG Qiwu;LI Xuewei;KONG Ning;WU Lina;LEI Zhiwu(School of Resources Environment and Safety Engineering,University of South China,Hengyang 421001,China;School of Resource and Environmental Engineering,Wuhan University of Technology,Wuhan 430070,China;Research Center for Eco-Environmental Sciences,Chinese Academy of Sciences,Beijing 100085,China;Hunan Province Cooperative Innovation Center for Nuclear Fuel Cycle Technology and Equipment,University of South China,Hengyang 421001,China)

机构地区：[1]南华大学资源环境与安全工程学院,湖南衡阳421001 [2]武汉理工大学资源与环境工程学院,湖北武汉430070 [3]中国科学院生态环境研究中心,北京100085 [4]南华大学核燃料循环技术与装备湖南省协同创新中心,湖南衡阳421001

出　　处：《金属矿山》2020年第11期134-140,共7页Metal Mine

基　　金：湖南省教育厅科学研究项目(编号:18C0448);南华大学核燃料循环技术与装备协同创新中心开放基金项目(编号:2019KFQ06);南华大学博士启动基金项目(编号:190XQD070)。

摘　　要：磷酸改性高岭土材料表面附载活性强的氢基团,可以与K^+发生化学吸附作用,但吸附过程中交换出来的氢离子逐渐累积会影响吸附反应的进行。通过机械球磨蛇纹石,使其结构中的羟基活化溶出,中和累积的氢离子,以促进磷酸改性高岭土材料对K^+的吸附。考察了球磨转速、磷酸改性高岭土(KP)与活化蛇纹石(MAS)的用量比、吸附时间、硝酸钾初始浓度等因素的影响,试验结果表明:当蛇纹石的球磨转速为500 r/min,KP与MAS的用量比为0.6∶0.4,吸附时间为120 min,初始浓度为300 mg/L时,K^+的实际饱和吸附量为30.25 mg/g,达到了工业应用的水平。K^+吸附饱和后的KP/MAS在蒸馏水中进行试验时,仅有不到5%的K^+被溶出,在2%的柠檬酸溶液中溶出8 h后K^+接近全部溶出,说明产品在水中溶解度较低,而在弱酸性环境下具有较好的缓释特性,有利于植物根部对养分的吸收。The phosphoric acid-modified kaolin material was used to take a chemical adsorption with K^+due to the active hydrogen groups on the surface,but the accumulation of H+will affect the adsorption reaction.The hydroxyl groups of antigorite were activated to release OH-by milling.The OH-was dissolved to neutralize the accumulated H+to promote the adsorption of K^+.The effects of factors such as milling speed,mass ratio of phosphoric acid modified kaolin(KP)and activated serpentine(MAS),adsorption time,and different initial concentrations were investigated.The results showed that the ball milling speed was 500 r/min,mass ratio of KP to MAS was 0.6∶0.4,the adsorption time was 120 min,and the initial concentration was 300 mg/L,the actual saturated adsorption amount of K^+was 30.25 mg/g,which reaches the level of industrial application.When K^+was adsorbed and saturated KP/MAS was tested in distilled water,only less than 5%K^+was dissolved out,and nearly all K^+was dissolved out after 8 h in citric acid solution with concentration of 2%,indicating that the product had low solubility in water,and had good slow-release characteristics under weak acid environment,which was conducive to the absorption of nutrients by plant roots.

关 键 词：磷酸改性高岭土 蛇纹石 钾离子 机械化学 吸附方程 

分 类 号：TF841.2[冶金工程—有色金属冶金]