Adsorption capacity of wollastonite based adsorbents with porous structure controlled with different progeny agents

Abstract

Porous wollastonite (WL) based adsorbents were fabricated by a pressureless sintering process by using low molecular weight poly(methyl methacrylate) (PMMA), nanocellulose (NC) and yeast as the pore forming agents. WL based adsorbents were synthesized in two step process. In the first step, calcium carbonate and methylhidrogen cyclosiloxane were mixed with isopropyl alcohol, dried and calcined at 250 °C. Second step included WL mixing with porogen, followed by controlled calcination and on that way the sintered materials with randomly distributed pores were obtained. The effectiveness of the synthesis steps as well as material properties, i.e., the pore morphology were determined by FTIR analysis and scanning electron microscopy (SEM), respectively. The pore morphology and adsorption capacity was changed dramatically by changing the pore forming agent. The highest adsorption capacity was obtained when NC was used as the pore forming agent. Obtained materials showed moderate adsorption capacities of 10.56, 8.42 and 11.33 mg/g with respect to As5+, Cr6+ and phosphate, respectively. The con centrations of heavy metal ions were determined by using Ion chromatography coupled with mass spectrometry (ICP-MS).