活性炭在不同浓度NaNO_3溶液中对硝基苯的吸附

研究了活性炭在不同浓度NaNO3溶液中对硝基苯的吸附行为,着重考察活性炭对硝基苯的吸附规律。结果表明,活性炭对硝基苯的吸附量大、吸附速度快,其吸附动力学可以用Lagergren伪二级速率方程很好拟合,吸附过程是双速过程;活性炭对硝基苯的吸附等温线符合Langmuir吸附等温式;不同浓度NaNO3溶液,对活性炭吸附硝基苯有很大影响。吸附动力学和吸附等温线实验均表明在低浓度和高浓度的NaNO3溶液中,活性炭对硝基苯的吸附量小于其在无NaNO3溶液中对硝基苯的吸附量,而在中等浓度的NaNO3溶液中,活性炭对硝基苯的吸附量大于其在无NaNO3溶液中对硝基苯的吸附量。

Adsorption of nitrobenzene on activated carbon in NaNO_3 solutions at different concentration

The adsorption behavior of activated carbon for nitrobenzene in various concentrations of NaNO_3 so-lutions was studied to investigate the law of nitrobenzene adsorption on active carbon. The results indicated that acti-vated carbon had great capacity and rapid speed for nitrobenzene adsorption. The process of adsorption was the two-speed process, and could be well described by pseudo second order model. The batch experiments data obeyed the Langmuir isotherm model, which indicated that the adsorption behavior was monolayer adsorption. The concentra-tions of NaNO_3 had significant impact on absorption capacity of active carbon, the capacity in low (0.001 mol/L) or high (0.100 mol/L) concentrations of NaNO_3 solutions was less than that in the solution without NaNO_3. In moder-ate concentration (0.010 mol/L) of NaNO_3 solution, however, the adsorption capacity was more than that in the so-lution without NaNO_3.