摘要
以凹凸棒石（AT）为导向硬模板，葡萄糖和氨水为原料，采用水热碳（C）化法一步制备出氨基化碳化凹凸棒石复合粉体，并用扫描电子显微镜、Fourier红外光谱、元素分析、Zeta电势、Raman光谱、热重分析对复合粉体进行表征分析，研究复合粉体对水中Cr（1Ⅵ）的吸附一还原性能。结果表明：氨基化碳化凹凸棒石复合粉体表面富含含氧基团（如羟基、羧基、酮基等）及氨基等活性基团。复合粉体对Cr（Ⅵ）和总铬去除率显著高于碳化凹凸棒石和AT，但和活性炭没有显著差异。复合粉体对Cr（Ⅵ）去除率显著高于总铬，表明复合粉体具有一定的还原性能；Cr（Ⅵ）和总铬去除率均随着Na2s04浓度的增加而减小。对总铬的吸附动力学过程符合准二级动力学模型。对总铬吸附过程适合用Langmuir模型来描述，在288、298、308、318和328K时，最大吸附量分别为81．5、92．6、109．9、120．5和132．7mg／g。在研究的温度范围内，Gibbs自由能变为-16．5～20．8kJ／mol，焓变为15．6kJ／mol，熵变为110．9～114．1J／（mol·K），表明该吸附是自发、吸热和熵增过程。
The AT@C-NH2 （amino-functionalized attapilgite@carbon composite） samples were synthesized via one-step hydrothermal carbonization of glucose and ammonia as raw materials, and using attapulgite as a hard template. The as-prepared composite powder was characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, chemical element analysis, Zeta potential measurement, Raman spectroscopy and thermo-gravimetric analysis, respectively. The adsorption and reduction properties of AT@C-NH2 were conducted through sequential batch adsorption experiments. The results indicate that oxygen-containing groups and amino groups are supported on the surface of AT@C-NH2, The removal rates of Cr （Ⅵ） and total chromium of AT@C-NH2 are greater than those of AT@C and AT, and little difference ofCr （Ⅵ） and total chromium removal rates between AT@C-NH2 and activated carbon was observed. The removal rate of Cr （Ⅵ） is greater than that of total chromium, indicating that AT@C-NH2 has a certain reducibility. The removal rates of Cr （Ⅵ） and total chromium reduce with the increase of sodium sulfate concentration, The adsorption kinetics for total chromium follows the pseudo second order kinetic model. The adsorption isotherms for total chromium can be described by the Langmuir equation, and the maximum adsorption capacities are 81.5, 92.6, 109.9, 120.5 and 132.7 mg/g at 288, 298, 308, 318 and 328 K, respectively. According to the three important thermodynamics parameters （i.e.,△H=-15.6 kJ/mol,-16.5≤△G≤-20.8 kJ/mol, and 110.9≤△S≤114.1 J/（mol-K））, the adsorption process is a spontaneous, endothermic and entropy increasing process.
作者
王诗生
盛广宏
宋西珍
王萍
于冬冬
练建军
WANG Shisheng;SHENG Guanghong;SONG Xizhen;WANG Ping;YU Dongdong;LIAN Jianjun(School of Energy and Environment, Anhui University of Technology, Ma＇anshan 243032, Anhui, China;Water Purification by Biofilm Method and Utilization, Engineering Research Center of Ministry of Education, Anhui University of Technology, Ma＇anshan 243032, Anhui, China)
出处
《硅酸盐学报》
EI
CAS
CSCD
北大核心
2018年第5期707-714,共8页
Journal of The Chinese Ceramic Society
基金
国家自然科学基金(41401553,51709001)资助项目
关键词
凹凸棒石
葡萄糖
氨水
六价铬
吸附-还原
attapulgite
glucose
ammonia
hexavalent chrome
adsorption and reduction
作者简介
王诗生（1975-），男，博士，副教授。
