Study of quench effect on heavy metal uptake efficiency by an aluminosilicate-based material

Quench is a widely used technique in organic synthesis or inorganic material treatment but only limited studies have been performed on aluminosilicate. In this work, the quench effect on the textural properties and surface functional groups has been studied by the functionalization of a waste-derived aluminosilicate material. The porous structure has been changed in the presence of a quench reagent. We consider that this difference originated due to the prevention of replacement of potassium atoms in surface ion-exchange sites by hydrogen atoms. Surface characterization including SEM, XPS and FTIR further confirmed the preservation of SiOK functional groups. Meanwhile, due to the differences between the electronegativities of potassium atoms and hydrogen atoms the ion-exchange ability for heavy metals of the quenched samples was significantly enhanced and this has been validated by adsorption experiments with various kinds of metals. The mass balance for leaching calcium and potassium atoms also revealed that the enhanced ion-exchange capacity was caused by the improved liberation of potassium and calcium atoms from the aluminosilicate network. Moreover, the leaching test for metal doped material shows a limited amount of metal leaching under acidic conditions, indicating the potential application of this material in industrial wastewater treatment or catalysis applications.