Adsorption Of Low-concentration Cu(â…¡) Ion With Chitosan

In this study,the related fundamental issues of treating the low Cu(â…¡) ion concentration in wastewater,using the adsorption technique were carried out to provide theoretics direction for further application.Select the degree of deacetylation of chitosan was 90.75%and molecular sieves type 4A as adsorption material,membrane had been made through the method of doctor-blade casting process and loaded molecular sieve,Comparative study of adsorption properties.In the static adsorption experiment on chitosan particle,the results indicated that the equilibrium time was about 8 h;high temperature was good for the adsorption.The best pH was about 8～9.Adsorption of low initial concentration of copper ion water can be made good adsorption.The sequence of the reaction condition that effected the adsorption is:CTS Amount＞reaction temperature＞reaction time＞pH.Adsorption process of chitosan membranes shorter time than particles,and other factors affecting the adsorption effect is similar to,12um thickness better absorption.The adsorption equilibrium time of molecular sieve type 4A is 2.5 h;The best pH was about 7;The sequence of the reaction condition that effected the adsorption for molecular sieve is:the initial Cu²⁺concentration＞reaction temperature＞reaction time.The adsorption factors of chitosan loaded molecular sieve influenced by the molecular sieve,longer than molecular sieve adsorption equilibrium time has been extended to 5h.The study of the kinetic equation on chitosan particles,molecular sieve membrane and its load after by dynamic adsorption experiments,the result in line with the mechanism of monolayer adsorption.The results showed the kinetics of ion exchanging was controlled by liquid film diffusion.The initial adsorption time of 30min to lh to achieve saturated adsorption amount of 90%The behavior of the chitosan,membrane and molecular sieve adsorption and exchange process was studied.Freundlich isotherm was more suitable for simulating the adsorption.The thermodynamic study of the adsorption process showed that the Cu adsorption-ion exchange process is spontaneous,endothermal,and the entropy is positive.The fourier transform infrared(FTIR) spectroscopy on blank and copper-loaded demonstrated that the groups of NH₂ and OH on particle involved in the coordination and NH₂ on membrane is better,the crystal structure change show that molecular sieve adsorption is the physics and chemistry of the dual role.