Biosorption of strontium ion by immobilised Aspergillus niger
Biosorption of strontium by Aspergillus niger immobilised in calcium alginate has been studied. The experimental data showed that immobilised A. niger was effective in removing Sr2+ from aqueous solution. The optimal pH and temperature were 3.0LC and 25LC, respectively. Pseudo second-order model was applicable to all the sorption data over the entire time range. Intraparticle diffusion was not the only rate-limiting step. Sorption data conformed well to both Langmuir and Freundlich isotherm model. The maximum adsorption capacity (qmax) niger was 751.88mg/g. The FT-IR analysis showed that the mechanism involved in biosorption of Sr2+ by A. niger was mainly attributed to Sr2+ binding of groups of amide groups I and II.
Keywords: Aspergillus niger, biosorption, heavy metals, immobilisation, strontium, calcium alginate, adsorption capacity