Alumina/activated carbon nano-composites: Synthesis and application in sulphide ion removal from water

An investigation of adsorption of sulphide ion (S^2-) in water onto carbon/alumina nano-composites synthesized from aluminium carboxylate precursors, in presence of HCl, NaOH, NaCl and surfactant is reported in this paper. A controlled oxygen free pyrolytic technique has been adopted for the synthesis of nano-composites, using acetate, acetyl acetonate, lactate and distearate of aluminium and activated carbon. XRD, SEM and TEM studies of the composites show that they contain clusters made of nano carbon particles of size 50-130nm into which nano alumina particles of size around 10nm are dispersed. While applying the adsorption data in Langmuir, Freundlich, Temkin and Dubinin-Raduskevich isotherm models, the data fit well with Langmuir model. All composites have increased porosity and decreased surface area compared to bare carbon. The adsorption capacity of composites obtained from acetate and lactate are higher and are found to be in the range of 71-200mg/g.