热解温度对制备不同类型秸秆生物炭及其吸附去除Cu^(2+)的影响

Effects of the Pyrolysis Temperature on Cu^(2+) Removal Efficiency and Different Kinds of Straw Biochars

[目的]探讨热解温度对制备不同类型秸秆生物炭及其吸附去除Cu^(2+)的影响。[方法]以玉米、水稻、芝麻3类秸秆为原料于400~700℃热解炭化制备生物炭,探讨热解温度对秸秆生物炭的结构官能团、比表面积、孔径分布等结构及理化性质的影响,并评价生物炭对Cu^(2+)的吸附性能。[结果]生物炭的pH和比表面积随热解温度的升高而逐渐增大,而产率却逐渐稳定,其中热解温度的变化对水稻和芝麻秸秆生物炭的影响更为明显;此外,生物炭对Cu^(2+)的吸附效率与生物炭的种类和热解温度有关,升高热解温度有利于提高生物炭对Cu^(2+)的吸附去除率,且水稻和芝麻秸秆生物炭的吸附效率明显高于玉米秸秆生物炭,其中700℃下热解所制备的水稻和芝麻秸秆生物炭对Cu^(2+)的去除率可达100%。[结论]该研究可为控制农业环境污染提供科学依据。

[Objective]To study the e-ffectsof the pyrolysis temperature on Cu2＋ removal efficiency and different kinds of straw biochars. [ Method]Three kinds of raw materials including rice,corn and sesame straw were used to prepare the biochars at the pyrolysis temperatures of 400 - 700 ℃ under the nitrogen atmosphere. Effects of the pyrolysis temperature on the structure, physicochemical property and Cu^2＋ removal efficiency of different kinds of straw biochars were investigated. [ Result ] The results showed that pH and specific area of straw biochars increased while yields of biochars decreased with increasing pyrolysis temperature, and their effects of pyrolysis temperature on rice and sesame series biochar were obvious. The adsorption efficiency of biochar on Cu^2＋ was related to the types and pyrolysis temperature of the straw raw material,and in- creasing the pyrolysis temperature was helpful to improve the adsorption rate of biochar on Cu2~ removal. Moreover,the removal rate of Cu^2＋ on rice and sesame straw biochars were higher than that on corn straw biochar. Among them,the removal rate of Cu^2＋ on rice and sesame biochar prepared at 700 ℃ can reach to 100%. [ Conclusion]The study can provide scientific basis for controlling agricultural environmental pollution.