柚子皮生物碳质对4-氯硝基苯的吸附动力学及吸附平衡特征  

Kinetics and equilibrium of 4-nitrochlorobenzene adsorption on biological carbon prepared by pomelo peel

作　　者：李登勇[1] 吴超飞[1] 韦朝海[1] 卢彬 

机构地区：[1]华南理工大学环境科学与工程学院,广州510006 [2]广州境天环保科技有限公司,广州510640

出　　处：《环境工程学报》2010年第3期481-486,共6页Chinese Journal of Environmental Engineering

基　　金：国家自然科学基金资助项目(20777018);国家"863"高技术研究发展计划项目(2006AA06Z378);"十一五"国家科技支撑计划重点项目(2008BAC32B06-1)

摘　　要：考虑到水环境或工业废水中低浓度、低溶解度有机氯化物的普遍存在,拟构建仿生吸附原理分离低剂量组分,选用柚子皮为生物质代表,在炭化温度为600℃的条件下制备生物碳质吸附剂,考察4-氯硝基苯(pCNB)的吸附特征数据,通过观察等温吸附模型和吸附动力学方程,分析了可能的吸附机理。研究结果表明,实验在25±1℃条件下,当初始浓度为35 mg/L,pCNB的吸附去除率为85.88%,吸附过程分成2个阶段,第1阶段为物理吸附,第2阶段为化学吸附,8 h达到吸附平衡;吸附反应符合二级动力学方程(R2=0.999),动力学参数k2为1.450 g/(mg.h),平衡吸附量qe为30.06 mg/g;吸附等温线结果表明,生物碳质对pCNB的吸附可以用Langmu ir模型很好描述,表面吸附在生物碳质对pCNB的吸附过程中占主导地位,柚子皮生物碳质对pCNB的最大吸附量达到64.52 mg/g,是从低浓度含pCNB废水中去除目标污染物的廉价与良好吸附剂。Considering the existence of the organic chlorides with low concentration and solubility in water environment or industrial wastewater,the simulation of a biomimetic adsorption principle to separate the low-dose component from water was studied.Pomelo peel was selected as the biomass and the carbonaceous adsorbents were prepared at 600℃ to investigate the pCNB＇s adsorption efficiency.The adsorption mechanism was proposed by studying the effect of substrate concentration on the adsorption effects,adsorption isotherm model and adsorption kinetic equation.It was found that pCNB removal efficiency was 85.88% and the first adsorption stage was physical adsorption,the second was chemical adsorption when its initial concentration was 35 mg/L at 25±1℃ and pCNB adsorption reached a balance after 8 h.The adsorption reaction was consistent with second-order kinetic equation（R2 =0.999）,kinetic parameter（k） was 1.450 g/（mg·h）,equilibrium adsorption capacity（qe） was 30.06 mg/g.Adsorption isotherm results showed that pCNB adsorption by biological carbon could be described well with Langmuir model,and surface absorption played a leading role in the process of pCNB adsorption into biological carbon.The largest amount of pCNB adsorption by pomelo peel prepared biological carbon was up to 64.52 mg/g,suggesting that the biological carbon could remove pCNB with low concentration in wastewater as a cheap and effective adsorbent.

关 键 词：生物碳质 动力学 仿生吸附 4-氯硝基苯 

分 类 号：X703[环境科学与工程—环境工程]