New organic–inorganic hybrid microporous organosilica having high metal ion adsorption capacity

Abstract

A new microporous organic–inorganic hybrid organosilica LHMM-2 containing a bis(propyliminomethyl)benzene moiety inside the framework has been synthesized hydrothermally without using any template or structure-directing agent. Powder XRD and TEM image analyses suggest a new disordered microporous structure with pores of dimension ca. 0.54 nm, and ¹³C and ²⁹Si MAS NMR and spectroscopic results indicate the presence of bridging organic bis(propyliminomethyl)benzene moiety in this framework. TPD-NH₃ results suggested that nearly 5 times as much bis(propyliminomethyl)benzene moiety is located inside the micropore walls (matrix) than in the surface of the pores. LHMM-2 shows very high adsorption capacity for metal cations like Fe³⁺, Cu²⁺ and Zn²⁺.