中文摘要：

以蔬菜废弃物（芹菜）为原料,采用限氧裂解法制备了500℃下的蔬菜废弃物基生物炭,利用SEM扫描电镜、EDS能谱分析、CHN元素分析、FTIR红外光谱、比表面积及孔径分析等方法表征生物炭的物理化学性质,探究生物炭对水溶液中Pb（Ⅱ）的吸附特性及其影响因素。结果表明,500℃下制备的废弃芹菜生物炭孔隙较少,具有较小的比表面积和丰富的官能团。废弃芹菜生物炭对Pb（Ⅱ）具有良好的吸附效果,在初始pH值为5、投加量为0.8 g/L、初始质量浓度为400 mg/L时,其最大吸附量为240.5 mg/g,且投加量、初始质量浓度和体系pH值的影响强烈。废弃芹菜生物炭对Pb（Ⅱ）的吸附在5 min内达到平衡,吸附过程更符合准二级动力学模型（R^2〉0.99）,表明其吸附速率主要受化学作用控制。同时吸附速率还受初始质量浓度的影响,初始质量浓度越低,吸附过程越先达到平衡。在试验范围内,等温吸附Langmuir模型和Freundlich模型都适合描述废弃芹菜生物炭对Pb（Ⅱ）的吸附过程。

英文摘要：

This paper takes it as its research objective to study the biochar in adsorbing lead（Pb（Ⅱ）） in the aqueous solution,and in turn to explore its adsorptive features.In order to study the adsorptive features of biochar,we have done a lot of experiments.First of all,we have chosen biochar from the waste-celery（Apium graveolens L.） as a raw material for preparing the adsorption agent via the pyrolyzation at a temperature of 500 ℃ in a condition with the limited amount of oxygen.And,secondly,the physicochemical properties of biochar can be characterized by using a SEM,EDS,CHN elemental analyzer to analyze its FTIR surface area and pore size.Thirdly,we have examined the effects of the dosage,the initial concentration,the pH value,the time length and the temperature adopted on the Pb（Ⅱ）-removing process and removing rate in our experiments,in addition to the analysis of the adsorption isotherm and adsorption kinetics regularity.The results of the said experiments indicate that the biochar of the discarded celery has left fewer pores after the experiment and a much smaller surface area though still functioning well.What is more,it can be found that,the adsorption efficiency can be made so high as 240.5 mg/g on the condition when the initial pH remains5 at the dosage of 0.8 g/L with the initial concentration being 400mg/L.Furthermore,the adsorption capacity and the removal efficiency curves also indicate that the biochar adsorption of Pb（Ⅱ）functions most efficiently in the dosage range between 0.5-1 g/L at the optimal initial concentration of 200 mg/L.We have made it also clear that the adsorption capability of the heavy metal contaminants tends to be dependent on some reaction factors,particularly that of pH.The absorption of the lead-affected pH value by the waste-celery biochar has been verified by our sequentially designed batch experiments.It has been made clear that the Pb（Ⅱ）adsorbed by the biochar tends to increase with the increase of the pH value from 1.49 to 5.33.Kinetic analysis