CAJ | 학술논문

从pH的影响、等温吸附、吸附动力学和热动力学4个方面研究了向日葵根分泌物对黄壤吸附Cd~(2+)的行为的影响.随着pH的升高,黄壤对Cd~(2+)的吸附量都升高,而且在pH为3～8的范围内,根分泌物的存在都减少了黄壤对Cd~(2+)的吸附.不论有否根分泌物存在,Langmuir方程和Freundlich方程能满意地描述黄壤对Cd~(2+)的等温吸附行为,黄壤对镉的吸附动力学符合拟二级速率方程,是一个墒减的放热的自发反应.向日葵根分泌物的存在抑制了黄壤对镉的吸附容量和吸附速率,并一定程度上降低了吸附过程的自发性.
종pH적영향、등온흡부、흡부동역학화열동역학4개방면연구료향일규근분비물대황양흡부Cd~(2+)적행위적영향.수착pH적승고,황양대Cd~(2+)적흡부량도승고,이차재pH위3～8적범위내,근분비물적존재도감소료황양대Cd~(2+)적흡부.불론유부근분비물존재,Langmuir방정화Freundlich방정능만의지묘술황양대Cd~(2+)적등온흡부행위,황양대력적흡부동역학부합의이급속솔방정,시일개상감적방열적자발반응.향일규근분비물적존재억제료황양대력적흡부용량화흡부속솔,병일정정도상강저료흡부과정적자발성.
The effects of root exudates from Helianthus annuus on Cd~(2+) adsorption to yellow earth were investigated in the present study. It was found that root exudates generally inhibited adsorption of Cd~(2+) onto yellow earth. Cd~(2+) adsorption capacity increased on increasing of solution pH and the presence of root exudates reduced Cd~(2+) adsorption capacity at pH 3 - 8-Cd~(2+) isothermal adsorption could be well represented with both Langmuir and Freundlich equations, and the adsorption kinetics with pseudo-second order equation. Cd~(2+) adsorption capacity to yellow earth is a spontaneous exothermic reaction.The presence of root exudates reduced the adsorption capacity and adsorption rate.