摘要
以玉米秸秆为原料,在300、450℃和600℃下裂解得到3种生物炭,通过批处理实验讨论了溶液初始pH值和裂解温度对玉米秸秆及其生物炭吸附Cr(Ⅵ)的影响,并用吸附动力学模型和等温吸附模型对实验结果进行拟合。结果表明:对于同种吸附材料而言,溶液初始pH值越低,玉米秸秆及其生物炭对Cr(Ⅵ)的吸附量越大;当溶液初始pH值为3或5时,对Cr(Ⅵ)的吸附性能大小顺序为:玉米秸秆>生物炭300℃>生物炭450℃>生物炭600℃;当溶液初始pH=1时,对Cr(Ⅵ)的吸附性能大小顺序为:生物炭300℃>玉米秸秆>生物炭450℃>生物炭600℃,且生物炭300℃对Cr(Ⅵ)的最大吸附量约为141.24 mg·g^(-1)。可见,溶液初始pH值越低,生物炭的裂解温度越低,越有利于生物炭对Cr(Ⅵ)的吸附。
Batch experiments were performed on Cr（ Ⅵ ） adsorption using four straw-based materials including corn straw and three kinds of biochar pyrolysed at 300 ℃, 450 ＊C and 600 ℃, respectively. The results showed that the Cr（ Ⅵ ） adsorption were significantly affected by initial pH and pyrolysis temperature. The data were described by kinetic and isotherm models, and showed that the adsorption of Cr（ Ⅵ ） was increased with the decrease of initial pH. The removal rates of Cr（ Ⅵ ） were decreased with the increase of the pyrolysis temperature at pH=3 or pH=5. The biochar pyrolysed at 300 ℃ had the best capability of removing Cr（ Ⅵ ） from aqueous solution at pH=l, and the maxi- mum adsorption quantity was 141.24 mg＂ g-1 approximately. It observed that both the lower initial pH and the lower pyrolysis temperature had positive effects on the removal of Cr（ Ⅵ ） from aqueous solution.
出处
《农业资源与环境学报》
CAS
2016年第5期443-448,共6页
Journal of Agricultural Resources and Environment
基金
国家级创新项目(201610019027)
