秸秆生物质炭对重金属Cd吸附效果的研究

Study on the Adsorption Effect of Straw Biochar on Heavy Metal Cd

为探究秸秆生物质炭对重金属Cd吸附的影响因素,比较不同条件下小麦、玉米和稻草秸秆生物质炭对重金属Cd吸附性能的影响。小麦和稻草秸秆生物质炭的吸附机理都符合准二级动力学模型,而玉米秸秆生物质炭的吸附机理符合Langmuir方程。三种秸秆生物质炭中的元素占比和产炭率均受到热解温度和时间的影响。另有实验研究表明玉米和稻草秸秆生物质炭对Cd的吸附能力在pH值7~8区间内,吸附效果相对较好。同时干湿交替老化过程的生物质炭吸附作用显著降低。通过探究三种秸秆生物质炭对重金属Cd的吸附效果,为重金属Cd选择合适吸附剂提供理论支持。

In order to explore the influencing factors of straw biochar on the adsorption of heavy metal Cd,the effects of wheat,maize and straw biochar on the adsorption performance of heavy metal Cd under different conditions were compared.The adsorption mechanism of wheat straw biochar conformed to the quasi-secondary kinetic model,while the adsorption mechanism of corn straw biochar conformed to the Langmuir equation.The proportion of elements in the three types of straw biochar and the charcoal production rate were affected by the pyrolysis temperature and time.Other experimental studies have shown that the adsorption capacity of corn straw biochar on Cd is in the pH value 7~8 range,and the adsorption effect is relatively good.At the same time,the adsorption effect of biochar in the alternating aging process of dry and wet was significantly reduced.By exploring the adsorption effect of three kinds of straw biochar on heavy metal Cd,this paper provides theoretical support for the selection of suitable adsorbents for heavy metal Cd.