摘要
采用静置吸附法,以芹菜渣为生物吸附剂,研究了其对Pb2+的吸附作用、吸附过程的影响因素、热力学和动力学行为。结果显示:芹菜渣对Pb2+的吸附率随其粒径的减小而增大;Pb2+初始浓度相同时,吸附率随芹菜渣加入量的增加而增大,芹菜渣加入量相同时,吸附率随Pb2+初始浓度的增加而增大;正交试验得到3因素对吸附效果的影响程度顺序为pH值>时间>温度,最优吸附条件为pH值4、吸附温度50℃、吸附时间5 h;芹菜渣对Pb2+的吸附以单分子层吸附为主,Freundlich吸附等温式能较好的描述其吸附热力学情况;芹菜渣对Pb2+吸附先是快速吸附,吸附时间超过40 min后为慢速吸附,芹菜渣对Pb2+的吸附动力学可以用二级动力学模型描述;对于50 mg/L的Pb2+溶液,芹菜渣为吸附剂时的最佳固液比为15 g/L;芹菜渣对低浓度(≤20 mg/L)Pb2+溶液的吸附效果好于活性炭。
By adsorption, this paper systematically studies adsorption and adsorption mechanism of Pb2＋ by celery residue. Experimental results showe that： with the smaller size of celery residue, Pb2＋. adsorption rate is increased. Under the same Pb2＋ initial concentration, with the addition of more celery residue, Pb2＋ adsorption rate is increased. Under the same addition amount of celery residue, with the addition of Pb2＋ initial concentration, adsorption rate is also increased. Orthogonal tests show that： the optimum adsorption conditions for the wastewater pH is 4, the temperature is 50 % and soaking time is 5 hour. The influence order of 3 factors is pH, soaking time and temperature. Celery residue on Pb2~ adsorption with single molecule layer absorption dominant, and adsorption isotherm is fit to Freundlich adsorption isotherm. The adsorption rate for celery residue to Pb2＋ is quick at the beginning, and then becomes slowly after 40min. Second kinetic model better describes the adsorption kinetics of celery residue. The best s/1 radio of Pb2＋ （50 mg/L） adsorption by celery residue is 15 g/L. In the low concentration of Pb2＋ solution（ ≤ 20 mg/L）, the adsorption of celery residue is better than activated carbon.
出处
《食品与发酵工业》
CAS
CSCD
北大核心
2011年第10期100-104,共5页
Food and Fermentation Industries
基金
山西省高校科技开发项目(20110021)
山西省青年科技研究基金(2011021031)
关键词
芹菜渣
PB2+
生物吸附
吸附等温线
吸附动力曲线
固液比
celery residue, Pb2＋ , biosorption, adsorption isotherm, dynamic adsorption curve, S/L radio
