Preparation Of Chitosan-copper Beads And Its Application In Water Treatment

Chitosan,a natural organic polymer polysaccharide,has a wide range of sources and is easily degradable.Because of a large amount of amino groups,It can be easily used in combination with various substances(heavy metals,dyes,etc.).At the same time,It has a wide application prospects in water treatment,metal extraction and recycling.The main purpose of this paper is to prepare a chitosan composite material,based on the original chitosan,to increase the specific surface area and porosity of the material,thereby the adsorption capacity for heavy metals,dyes and other pollutants will be increased.The main work is to turn the chitosan acetic acid solution into beads by copper sulfate.Then,through the simple test of different contaminants by chitosan-copper besds,the selectivity of chitosan-copper beads to pollutants and their saturated adsorption capacity were be realized.The size and internal morphology of the chitosan-copper beads were adjusted by controlling the temperature of the chitosan acetic acid solution and the coagulating solution.Scanning electron microscopy(SEM),energy dispersive X-ray spectroscopy(EDX)and other characterization methods were used to observe the internal and external structural features of the chitosan-copper beads and the distribution of Cu.The results show that when the temperature of the coagulation bath is 50 °C,the acetic acid escapes at a uniform velocity.The internal structural is a honeycomb-like,and the distribution of the cell structure is uniform.Also the content and distribution of Cu are same.The formation mechanism of chitosan-copper beads was investigated by means of Fourier transform infrared spectroscopy and X-ray diffractometry(XRD).It can be found that the formation of beads is mainly due to the rock reaction with Cu ion and amino group in chitosan,which will form a metal skeleton structure.Through the static adsorption test of different dyes by chitosan-copper beads,it can be found that the adsorption of methyl orange(MO),Congo red(CR),and fluorescent peach B is higher.The ion exchange of different heavy metal ions by chitosan-copper beads shows that the effect of Cd and Cr was better.And the saturated exchange capacity of chitosan-copper beads of Cr and Cd was 74.30 mg/g(1.43 mmol/g)and 412.19 mg/g(3.68 mmol/g)respectively.Since both chitosan and Cu ion have excellent antibacterial properties,the properties of the resulting chitosan-copper beads are better than the raw materials themselves when the two interact.Antimicrobial tests on mold,Escherichia coli and Staphylococcus aureus by chitosan-copper beads revealed that the beads have long-term effective antibacterial effects against the above three strains.At the same time,it does not affect the physical and chemical properties of the beads themselves and can be used repeatedly.On account of the beads have good antibacterial effect on various dyes and heavy metal ions,and its antibacterial effect on various strains is obvious,it have broad application prospects in the field of water treatment.