Sintesis Biodiesel Minyak Ampas Tahu Terkatalisis Lempung Termodifikasi Kalsium Oksida dengan Pemanasan Microwave

Abstract

Biodiesel telah menjadi sumber energi alternaltif yang terus dikembangkan. Pada penelitian ini telah dilakukan sintesis biodiesel dari minyak ampas tahu menggunakan katalis lempung termodifikasi Kalsium Oksida (CaO) dengan pemanasan microwave untuk menghasilkan biodiesel. Sintesis Katalis lempung termodifikasi CaO menggunakan metode impregnasi basah. Sistesis biodiesel dari minyak ampas tahu melalui reaksi transesterifikasi dengan variasi jumlah katalis lempung termodifikasi CaO 1, 2, 3, 4, 5 % (b/b) dan variasi daya microwave 150, 300, 450, 600, dan 800 watt. Katalis Lempung termodifikasi CaO dikarakterisasi SEM EDX (Scanning Electron Microscopes/Energy Dispersive X-Ray) dan uji kebasaannya dengan metode Hammet. Produk biodiesel dikarakterisasi dengan Gas Chromatography-Mass Spectroscopy (GC-MS). Hasil karakterisasi menunjukkan bahwa biodiesel minyak ampas tahu telah berhasil disintesis. Biodiesel optimum dicapai pada jumlah katalis lempung termodifikasi CaO sebesar 3% dan daya microwave 600 watt dengan waktu reaksi 15 menit sebesar 90%. Terbentuknya biodiesel dibuktikan dengan beberapa puncak metil ester yaitu metil oleat (59,88%), metil palmitat (36,74%), metil stearat (2,94%), dan metil miristat (0,28%).

Biodiesel has become an alternative energy source that continues to be developed. In this study, biodiesel was synthesized from tofu dregs oil using a clay modified calcium oxide (CaO) catalyst with microwave heating to produce biodiesel. Synthesis of clay modified CaO catalyst using wet impregnation method. Synthesis of biodiesel from tofu dregs oil through transesterification reaction with variations in the amount of modified clay catalyst CaO 1, 2, 3, 4, 5 % (w/w) and variations in microwave power 150, 300, 450, 600, and 800 watts. The CaO-modified clay catalyst was characterized by SEM EDX (Scanning Electron Microscopes/Energy Dispersive X-Ray) and tested for basicity using the Hammet method. The biodiesel products were characterized by Gas Chromatography-Mass Spectroscopy (GC-MS). The characterization results show that the tofu dregs oil biodiesel has been successfully synthesized. Optimum biodiesel was achieved at 3% CaO-modified clay catalyst and 600 watt microwave power with a reaction time of 15 minutes by 90%. The formation of biodiesel was evidenced by several peaks of methyl esters, namely methyl oleate (59.88%), methyl palmitate (36.74%), methyl stearate (2.94%), and methyl myristate (0.28%).