The Adsorption Effect and Influencing Factors of Straw Biochar on Cu (Ⅱ) Pollution in Brown Earth
Two kinds of straw biochar were made from cotton stalks and peanut straw with the method of limited oxygen thermal cracking under the temperature gradient of 350 ℃,500 ℃ and 650 ℃.The adsorption characteristics and remediation effect of the two kinds of biochar to Cu (Ⅱ) were studied by adsorption kinetics and isothermal adsorption experiments in Brown Earth.The results showed that the degree of carbonization and BET specific surface area increased with the increase of pyrolysis temperature,while oxygen functional groups decreased,the rates of H/C and O/C decreased gradually.The differences in adsorption effect and mechanism were found between the different kinds of biochar made in different temperatures.In addition,the effect of biochar on Cu (Ⅱ) adsorption could fit well with the secondary dynamics equation of Lagergren dynamics equation and Langmuir isotherm equation.The adsorption capacity increased with the increasing in pH,with the maximum at pH 6.5.And the absorption capacity of peanut biochar was more than that of cotton.SEM scan image showed that the surface feature and space structure of peanut straw biochar were significantly higher than those of cotton.The spectrum analysis of FTIR showed that the content of oxygen functional group in straw biochar decreased with the increase of pyrolysis temperature.In summary,peanut straw biochar had significant remediation effect on Cu (Ⅱ) pollution in Brown Earth of Shandong Province.
NETL
NSTL
万方数据
维普
