Development of nano-silver doped zeolite A synthesized from Nigerian Ahoko kaolin for treatment of wastewater of a typical textile company

Abstract

In this work, nano-silver synthesized with mango leaf extract as a reducing agent was doped onto synthesized zeolite A (SZA), produced from Nigerian kaolin via green synthesis route. The produced adsorbents were characterized using X-ray fluorescence (XRF), X-ray powder diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), Fouriertransform infrared spectroscopy (FTIR) and Brunauer–Emmett–Teller (BET) surface analysis, in addition, it is to be used for the treatment of local textile effluent. The physicochemical parameters of the effluent were analyzed using standard methods. The HRTEM micrographs revealed well dispersed AgNPs on SZA and the BET surface area revealed high surface areas of 119.98m2/g and 436.44m2/g for SZA and silver-doped zeolite A (SDZA), respectively. The array of removal of the pollutants was BOD>COD>CN->Cl->NO2 ->TOC for SZA and CN->BOD>COD>NO2 ->Cl->TOC for SDZA, with the doped adsorbent removing the higher pollutants in all cases. Isothermal models indicated that Jovanovic model (R2>0.999) was most suitable for describing the adsorption process, which conformed to pseudo-second order kinetics with intraparticle diffusion of micropore type. The thermodynamic studies showed spontaneous and endothermic reactions.