Research On Synthesis And Characterization Of Novel Multi-functional Group Chelate Fibers And Their Adsorption Properties Of Heavy Metal Ions

With the rapid development of modern science and technology, the effluents from factories flowed into the groundwater system, polluted our water resources. Heavy metals are great contaminants to environment, once enter into water or soil, it is difficult to be remove, even with trace amount. They were linked with risks for human beings such as delayed development, various cancers, kidney damage, even death in some cases. Nowadays, a number of technologies have been used to remove heavy metals from aqueous solutions primarily including chemical precipitation, coagulation and flocculation, chemical reduction-oxidation, electrochemical treatment, ion-exchange and adsorption. However, most of them have disadvantages such as secondary pollutions, inefficiency, and uneconomical.Chelate fibers were known as novel valuable adsorbent materials because of their excellent properties. In this paper, two chelating fibers containing different functional groups were produced by modifying polyacrylonitrile fiber, and their functional groups were characterized to confirm by infrared spectroscopy. The impact of pH, adsorption time, initial metal ions concentration, and adsorption temperature on chelate fibers adsorption properties were studied. It was found that, two kinds of chelating fibers had good adsorption effect on Cu2+. The adsorption kinetics results indicated that the two types of chelating fibers followed second order model. Thioamide fiber adsorption process was controlled by particle diffusion. Hydroxamic acid fiber adsorption process was controlled by chemical adsorption and particle diffusion, but mainly by chemical adsorption. The thermodynamic data showed the behavior Cu2+absorbed on two chelating fibers accord with Langmuir equivalent temporation adsorbing model, the adsorption was a monolayer one. In the Proeess,△H is Plus and△G is negative, indicated that the adsorption of two kinds of chelating fibers for Cu2+is spontaneous and endothermic. Both the adsorbent could be regenerated at least six cycles without visible loss of adsorption capacities.The process parameters of adsorption in practical application were simulate through pilot scale experiments, which found that hydroxamic acid fibers was environmentally friendly materials with fine adsorption properties, and could be reuse. They can effectively remove heavy metal ions in wastewater, are suitable to be extended to practical applications.