Chitosan/Inorganic Porous Materials And Its Adsorption Capbility For Cu²⁺,Pb²⁺

Some industrial processes result in the release of heavy metals into the aquatic ecosystem. This has led to increasing concern about the effects of toxic heavy metals as environmental pollutants. The development of adsorption and separation technology has a better application in the future. The need for economical, effective, and safe methods for removal of heavy metals from wastewater has directed attention to low-cost natural sorbents. So macroporous materials and porous composite materials with high surface areas or high efficiency have been to be a trend in the treatment of wastewater.In this dissertation, porous composite materials were fabricated from chitosan and inorganic materials such as zeolite and graphite oxide through ice template- unidirectional freeze-drying technology, and the factors that affected the porous structure of the composite porous materials were explored. The structure of porous composites materials were characterized by IR and SEM and their properties were tested through percent water absorption. Meanwhile, the absorbing ability for the metallic ions such as Cu²⁺ and Pb²⁺ was investigated and some factors such as amount,crossling,pH,time,EDTA et al for metal absoring ability were confirmed. In the end, the desorption rate and reused efficiency of porous composites materials were also investigated.The results appeares that chitosan porous material as a effective coagulating agent has much better adsobring ability for metallic ions such as Cu²⁺ and Pb²⁺ than chitosan particles, especially for Pb²⁺. The major factors of affecting absorption are pH and chelaing action of EDTA and chitosan, which plays an important part during the adsorption. As compared with chitosan porous material, CS/Zel porous composite has poor adsorption, but CS/GO porous composite possesses resirable characteristics. Not only does it present high adsorped capcity for Cu²⁺ and Pb²⁺, but also it is easy to regeneration and reuse for many times in the practical treatment.