Studies On Syntheses And Adsorption Properties For Metal Ions Of Novel Chelating Adsorbents

The environmental pollution of heavy metal ions(HMI) has already become serious problems that influence the survival environment of human being and other creatures. It will have wide application prospect in environment protection, resources recovery and reclamation to find a good and cheap adsorbent, which are both environmental friendly and can adsorb HMI effectively. In this thesis, three kinds of chelating resins that function as adsorption and separation were prepared. The structures were characterized by FTIR. The properties of the chelating adsorption and the mechanism for many metals ions were studied.1. Two new types of snake-cage type cellulose chelating resins were synthesized by using new methods. The optimum synthesis conditions, the selling properties and reclamation were discussed. Their static adsorption properties for Cd~2+, Pb~2+, Fe~2+, Mn~2+, Pd~2+, Ag~+, Cr~3+, Hg~2+, as well as adsorption mechanism etc. were also systematically investigated. The experimental results showed that: (1) The above-mentioned resins had many advantages such as simple producing process, low cost, swelling in acid or base solutions without flowing away, easily degraded in nature and no secondary repollution. (2) The resins had also powerful adsorption capacities for Cd~2+, Ag~+, Cr~3+, Pb~2+, especially Cd~2+, Ag~+, which were 3~4 mmol-g~-1, what's more, they had also high adsorption capacities after being regenerated. Therefore, the resins are promising to be widely used in dealing with industrial sewage containing Cd~2+, Cr~3+, Pb~2+and recovering Ag~+. (3) From the study of adsorption dynamics, it could be found out that there were more than one mechanism during adsorption process .The snake resin and cage resin had the complication reactions with the metal ions. (4) From the study of isothermal adsorption, it was demonstrated that adsorption process could be described by the Langmuir or Freundlich equation within the range of experimental concentrations and was monomolecular adsorption. (5) The optimum pH, which was the major factor influencing the adsorption of the metal ions, was 5~6. The lower temperature was suitable to adsorption.