Effect of binders on porous properties, surface chemical properties and adsorption characteristics of granular adsorbents from sewage sludge

Abstract

To investigate the influence of binders on porous properties, surface chemical properties and methylene blue adsorption characteristics of granular adsobents from sewage sludge, four samples (G1, G2, G3 and G4) respectively using soluble starch, sodium carboxymethyl cellulose, sodium silicate and calcium sulfate as binders and a sample without binder (G0) were prepared by carbonization method. The pore structure and surface characterization of samples prepared show that G1 and G2 have many microporous and mesoporous pores while the activation of sodium silicate and calcium sulfate cause that G1 and G2 are typical mesoporous adsorbents. The FTIR spectra of all samples suggest that the major differences of surface functional groups are between (1000 – 1200) cm–1 and (400 – 800) cm–1. Langmuir model fitted the methylene blue (MB) adsorption data better, and the MB adsorption of G0, G1, G2, G3 and G4 are 56.50, 40.32, 33.44, 29.33 and 71.94 mg/g, respectively.