Biosorption Of Nickel And Copper Onto Treated Alga Undaria Pinnatifida

Biosorption of nickel and copper ions from aqueous solution onto treated alga biomass Undaria pinnatifida which was artificially cultured in Dalian has been studied and the Langmuir,Freundlich and Temkine equilibrium isotherms,pseudo-first-order,pseudo-second -order and intra-particle diffusion kinetic model were determined respectively.Mechanism and membrane reactor experiment are brought at the second and final part.Within the test range(initial concentration 5-50 mg/L,biosorption doze 0.1-0.5 g,pH 3-7), biosorption performance for metal ions showed an increase in specific metal uptake capacity with an increasing in initial ions concentration and decreasing in biosorbent doze.The optimized condition of pH value for nickel and copper is 4.7 and 4.0 respectively,while contact time is about 100 min.At equilibrium,the maximum total uptake by Undaria pinnatifida was 24.71 mg/g for nickel and 38.82 mg/g for copper.The results for nickel and copper fit well to the Langmuir and the Temkin isotherm respectively.Pseudo-second-order model described well the sorption kinetic of nickel and copper ions in comparison to pseudo-first-order and intra-particle diffusion kinetic model.Then the mechanism about the adsorbent and the ions has been discussed.It is deemed to the adsorbent was changed from a catenarian to a retiary structure after treated.It is propitious to adsorb the metal ions.Ions of the solution can be considered to be[M²⁺]than[M(OH)⁺]at the optimized pH value.FTIR results indicate that the CaCl₂ treated biosorbent impacted the -OH and C=O stretching.It means that adsorption is closely contact with the -COOH.It also indicate that the ion on the biomass surface may not only due to the ion exchange but also due to the chelation interaction during the adsorption process.The final part aims at developing a simple and practical methods to study the effect of a submerged membrane adsorption hybrid system.Adsorption kinetic study was first carried out with treated biomass for removing copper ions from a synthetic wastewater.A series of short-term experiments were conducted with preadsorption at different operating conditions such as biosorption time and continuous.Biosorption performance for the membrane reactor show a higher capacity to the higher initial concentration.It has a ion removal of 50%at the intial concentration 45mg/L and 80%at the intial concentration 10mg/L.It is suggested that a multipolar reacter can be used for reclaiming the metal ions.