Thermodynamics of Cr(Ⅵ)Adsorption in Biological Adsorbent by Calcined Shrimp Shells

Used raw shrimp shells as raw material were prepared into biomass carbon materials at the N₂ environment by tube furnace,which were characterized by field emission scanning electron microscopy(FE-SEM),transmission electron microscope(TEM),automatic surface area and pore size analyzer,X-ray single crystal diffraction(XRD)and infrared spectrometer(IR). Then the adsorption characteristics of shrimp shells biomass carbon for Cr(Ⅵ)was analyzed. The results showed that shrimp shells biomass carbon was activated at the temperature of 800℃,which presented at the high surface area(up to 137.942 m²/g)was 4 times before activation and the main component was CaO. It was also found that biomass carbon dosage and pH had a great effect on the adsorption capacity of Cr⁶⁺,and the adsorption of Cr⁶⁺ was conformed with Freundlich and Langmuir adsorption isotherm model. Therefore,the shrimp shells biomass had good adsorption properties,which could be made into a natural green water treatment agent.