Aceh Local Dolomite Modified by Alkali Metals as a Low-Cost Solid Inorganic Catalyst for Biodiesel Synthesis

Abstract

Solid inorganic-based catalyst which mainly contains calcium oxide and magnesium oxide has been successfully prepared from local Aceh dolomite minerals. The calcination process of dolomite particles (150 μm) in the air environment for 4 hours changed those calcium and magnesium carbonates compounds into their oxide form, which are subsequently referred to as inorganic oxides. Furthermore, the calcined local dolomite has been chemically modified using alkaline metal precursors (lithium, sodium and cesium precursors). Physicochemical investigation on the modified dolomite indicated that introduction of lithium metal on modified dolomite surface has a positive impact on increasing the number and strength of basic sites on the catalyst. The modified catalyst had proved its catalytic activity for biodiesel synthesis with the yield values of 82;78;51 respectively.