Modification Of Chitosan And Study Of Its Adsorbent Activity

The adsorbent activity of heavy metal Cu2+ , Cr6+, Ni2+ , Co2+ by modified-chitosan is discussed in this article.First, by cross-experiment, the condition of the reaction of chitosan, NH4CNS and C1CH2COOH is researched. The best one is that proportion l:1.2:1.2,temperature 30 ,time 3h.Then NCTS which is water-soluble is synthesized.Second, use ECH as cross-bonding reagent. The best cross condition is that: dosage 0.7ml/gNCTS, time 8h.The production(CNCTS) is water-fast.Last, the static state adsorbent activity is studied from six aspect namely, adsorptive capacity , adsorptive kinetics , adsorptive isotherm medium acidity , adsorptive selectivity and regeneration.The experiment indicates that:(1)CNCTS does not fit to treat the oxidizing wastewater.(2)The adsorptive capacity of Cu2+, Ni2+ decreases with its value of 2.39mmol/g and 1.60mmol/g separately; the adsorptive capacity of Co2+ increases because of new function-group.(3)The adsorption process follows Langmuir isothermal equation, and the adsorptive speed is quicker than chitosan does.(4)The adsorption of Cu2+, Ni2+, Co2+ by the sorbent CNCTS is exothermic reaction(5)The sorbent CNCTS can select Cu2+ when Cu2+, Ni2+, Co2+ coexist; and select Co2+ when N i 2+, Co2+ coexist.(6)The sorbent CNCTS can be regenerated.