Room temperature fabrication of cobalt mullite for the snappy adsorption of cationic and anionic dyes

Abstract

Cobalt mullite adsorbent for the robust adsorption performance towards Victoria Blue (VB) and Metanil Yellow (MY) is fabricated by the sol-gel method at room temperature using dipropylamine as a structuredirecting agent. The synthesized adsorbent is characterized by XRD, FT-IR and HRTEM. From these analyses, it is found that dipropylamine binds with the alumina and cobalt oxide which makes it into tetrahedral to octahedral form. This interaction causes the formation of cobalt mullite. It is observed that trigonal alumina and orthorhombic cobalt mullite are interlinked to form a hybrid network. The special feature of adopting this adsorbent for the adsorption of VB and MY is that it has a large amount of Brønsted acid site because of the octahedral coordination of Al and Co. The large availability of acid sites HighlightsCobalt Mullite is successfully fabricated by sol-gel method at room temperature.Aluminosilicate has tetrahedral framework, but introduction of Co 2+ into it make a hybrid network of tetrahedral and octahedral resulted in the formation of cobalt mullite in the framework.The hybrid framework generate more acidity which aid faster adsorption rate with higher adsorption capacity of VB and MY.