摘要
目的探究硝酸改性活性炭对水中百草枯的吸附效果。方法以椰子壳为原料、硝酸为活化剂加热,制备椰壳活性炭,以制得的最优炭YK-7为研究对象,探究百草枯溶液pH、溶液初始浓度、活性炭投加量、振荡速度、温度对百草枯吸附效果的影响,采用Boehm滴定法和液态氮吸附对活性炭进行了表征。结果表明在弱碱环境下,有利于百草枯的吸附;提高百草枯初始质量浓度和温度均可以提高吸附量,增加投加量却不利于吸附量的增加;在硝酸改性的基础上热处理可以进一步提高吸附量。结论硝酸改性提高了百草枯的吸附量和吸附速率,吸附过程受溶液pH、初始浓度、活性炭投加量、振荡速度和温度的影响,其吸附百草枯的行为符合准二级动力学模型。并且吸附是一个吸热过程,具有一定的化学吸附作用。
Objective To explore the effects of nitric acid-modified activated carbon on absorption efficacy of paraquat in water.Methods With coconut shell as raw material and nitric acid as activator,coconut shell activated carbon was prepared,which produced the optimal carbon YK-7 as the research object.The effects of paraquat solution pH,solution initial concentration,activated carbon additive quantity,shock velocity and temperature on the adsorption efficacy of paraquat were investigated.Boehm titration and liquid nitrogen adsorption were performed to analyze the adsorption characterization of activated carbon.Results The environment of weak base was helpful for paraquat adsorption.The increased paraquat initial concentration and temperature improved the adsorption quantity.Increase of the dosing quantity was not conducive to increasing the adsorption quantity.Nitric acid-modified adsorption heat treatment increased absorption efficacy.Conclusion Nitrate modification could improve the adsorption capacity and adsorption rate of paraquat,which was dependent on the solution pH,initial concentration,activated carbon adsorption process additive amount,the influence of the shock speed and temperature.The adsorption behavior of paraquat fitted level 2 dynamic model.Adsorption was an endothermic process and had a certain chemical adsorption.
作者
范凯轩
张鹃
刘雨瑶
Fan Kaixuan;Zhang Juan;Liu Yuyao(Department of Analytical Chemistry,School of Pharmacy,Zunyi Medical University,Zunyi Guizhou 563099,China)
出处
《遵义医科大学学报》
2022年第4期444-449,共6页
Journal of Zunyi Medical University
关键词
活性炭
改性
百草枯
吸附
activated carbon
modification
paraquat
adsorption
