本实验选用由芦苇秸秆制备的生物炭，通过研究吸附等温线、吸附动力学以及生物炭投加量和溶液pH对生物炭吸附Ni2＋的影响，以确定其对水体中Ni2＋的吸附特性．结果表明，Ni2＋初始浓度在0．5—12 mg·L－1范围内，Langmuir模型能很好地描述生物炭对Ni2＋的等温吸附规律，其理论饱和吸附量为12．10 mg·g－1，与实际饱和吸附量11．93 mg·g－1相近．生物炭对Ni2＋的吸附动力学过程符合准二级动力学模型，通过颗粒内扩散方程可得具体吸附过程由膜扩散和内扩散共同控制．随投加量增加，生物炭对Ni2＋的吸附量下降，而去除率则上升，当投加量＞30 mg时，Ni2＋的去除率接近100％．溶液pH值在1—12范围内，Ni2＋的去除率随pH值的升高而增加，当pH ＞10时，Ni2＋的去除率同样接近100％．
Adsorption isotherm, kinetics and influcing factors such as biochar mass and solution pH were investigated to determine the adsorption characteristics of Ni2+ onto reed straw biochar in aqueous solution. The results showed that the adsorption isotherm of Ni2+ onto biochar could be well described by Langmuir model with Ni2+concentration between 0.5 mg·L-1 and 12 mg·L-1, and the theoretical maximum adsorption was 12.10 mg·g-1 , which was in good accordance to the experimental value (11.93 mg·g-1). The adsorption process could be well fitted by pseudo?second?order model, and through intraparticle diffusion model, the specific process was controlled by both membrane diffusion and internal diffusion. With increasing biochar mass, Ni2+ adsorption decreased but its removal rate increased. When the mass was above 30 mg, the removal rate approached 100%. In the pH range of 1—12, the removal rate of Ni2+ enhanced significantly with increasing pH in aqueous solution. When the pH was above 10, the removal rate also approached 100%.
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