红壤对铝锰离子的吸附特征 Ⅳ.铝锰交换钙钾离子的化学现象

铝、锰离子与钙或钾质固相之间的交换吸附也出现非等当量交换和非电性吸附,而钙、钾离子对交换反应则为电性吸附;非电性吸附量决定于固相表面的场强,也与离子的水解性质和价数有关,其中以铝离子在砖红壤、红壤中的非电性吸附最为强烈;从能量角度综合说明了k、K、1/ n 与ΔF的联系,铝离子的交换吸附具有最大的k、K和最小的1/ n,ΔF为负值;从热力学进一步证论了红壤铝质化的机理,在自然条件下红壤酸化应是一个连续的自发和不可逆过程。

EXCHANGE-ADSORPTION CHARACTERISTICS OF ALUMINIUM AND MANGANOUS IONS BY RED SOILS Ⅳ. CHEMICAL PHENOMENON FOR EXCHANGE OF CALCIUM/POTASSIUM ION BY ALUMINIUM/MANGANOUS IONS

Nonequivalent exchange and nonelectrostatic adsorption also appeared during exchange-adsorption between Ca-/K-solid phase and aluminium/manganousions,while exchange reaction for calcium and potassiumion pair was electrostatic adsorption.Amount of nonelectorstatic adsorption was controlled both by field intensity of solid surface and hytrolysis nature of ion and its valence number,in which aluminium had the largest value in laterite.The relation between k,K,1/n and ΔF was comprehensively explained from enengy concept,exchange adrorption of aluminium with the largest k,K and the smallest 1/n, hence with negative ΔF.The mechanism for basicions to aluminium transformation in red soil,namely acidification,which was an irreversible and continuously spontaneous proccesses under natural conditions,was proved in thermodynamics.