通过考察β-硅酸二钙(β-C2S)对腐殖酸钠的吸附动力学及热力学,研究了其对腐殖酸钠的吸附行为,并探讨了吸附前后β-C2S表面zeta电位的变化规律。结果表明:根据吸附等温曲线的相关数学模型拟合,得出β-C2S对腐殖酸钠的吸附过程符合Langmuir吸附等温式模型,同时符合二级吸附动力学。吸附自由能变为–20~0kJ/mol,表明此过程属于物理吸附和化学吸附共存,以物理吸附为主的自发吸热过程。表面zeta电位的测定表明在铝酸钠溶液中β-C2S表面带负电荷。
The characteristics of absorption of sodium humate on β-dicalcium silicate(β-C2S) were studied by investigating the absorptive thermodynamics and dynamics.The zeta-potential of β-C2S surface before and after sodium humate adsorpted on was analyzed.The results show that the adsorption process follows the comparatively isothermal adsorption equation of Langmuir according to the second order adsorption kinetics for the adsorption isotherm.All of Gibbs free-energy change are between 0 and –20kJ/mol,and the absorption process is a spontaneous endothermic process with the physical adsorption which is the main cause and chemical adsorption.The zeta potentials show that the surface of β-C2S has negative electrical charges in sodium aluminate solutions.