Pemanfaatan Nanokatalis CaO/Lumpur Lapindo pada Reaksi Transesterifikasi Minyak Jelantah Menjadi Biodiesel

Utilization of CaO/Lumpur Lapindo Nanocatalists in the Transesterification Reaction of Waste Cooking Oil into Biodiesel

Peningkatan penggunaan bahan bakar fosil secara global menyebabkan penipisan cadangan energi serta dampak negatif lain seperti polusi udara dan pemanasan global. Salah satu alternatif bahan bakar yang sifatnya dapat diperbarui dan lebih ramah lingkungan adalah biodiesel. Penelitian ini bertujuan untuk mensintesis biodiesel dari minyak jelantah melalui reaksi transesterifikasi dengan bantuan nanokatalis berbasis Lumpur Lapindo yang terimpregnasi kalsium oksida. Kalsium oksida diperoleh dari dekomposisi kalsium asetat. Variasi konsentrasi impregnasi kalsium oksida yang digunakan adalah 0%, 20%, 30%, dan 40%. Nanokatalis dibuat melalui proses ball milling selama 1 jam pada kecepatan 4000 rpm dengan rasio berat bola terhadap katalis sebesar 12:1, menghasilkan nanokatalis ₀CaO/LM, ₂₀CaO/LM, ₃₀CaO/LM, dan ₄₀CaO/LM. Karakterisasi katalis dilakukan dengan FTIR, XRD, XRF, PSA, dan SEM. Reaksi transesterifikasi berlangsung pada suhu 65°C selama 2 jam, dengan rasio mol minyak terhadap metanol 1:9 dan berat katalis 3% dari berat minyak. Hasil rendemen terendah diperoleh pada katalis ₀CaO/LM sebesar 77,36%, dan tertinggi pada ₄₀CaO/LM sebesar 93,27%. Biodiesel dikarakterisasi menggunakan GC-MS, menghasilkan persentase metil ester tertinggi pada biodiesel ₀CaO/LM, yaitu 99,26%, serta nilai densitas 929,4 kg/m³, viskositas 4,52 mm²/s (cSt), kadar air 0,097%, dan bilangan asam 0,50 mg-KOH/g.

The increasing use of fossil fuels globally leads to the depletion of energy reserves and other negative impacts such as air pollution and global warming. One alternative fuel that is renewable and more environmentally friendly is biodiesel. This study aims to synthesize biodiesel from waste cooking oil through a transesterification reaction using a Lapindo mud-based nanocatalyst impregnated with calcium oxide. The calcium oxide was obtained from the decomposition of calcium acetate. The variations in calcium oxide impregnation concentration used were 0%, 20%, 30%, and 40%. The nanocatalyst was prepared using a ball milling process for 1 hour at a speed of 4000 rpm with a ball-to-catalyst weight ratio of 12:1, resulting in nanocatalysts ₀CaO/LM, ₂₀CaO/LM, ₃₀CaO/LM, and ₄₀CaO/LM. Characterization of the catalysts was done by FTIR, XRD, XRF, PSA, and SEM. The transesterification reaction took place at 65°C for 2 hours, with an oil-to-methanol mole ratio of 1:9 and a catalyst weight of 3% of the oil weight. The lowest yield was obtained at ₀CaO/LM catalyst of 77.36%, and the highest at ₄₀CaO/LM of 93.27%. The biodiesel was characterized using GC-MS, resulting in the highest percentage of methyl esters in the ₀CaO/LM biodiesel, which was 99.26%, as well as a density value of 929.4 kg/m³, viscosity of 4.52 mm²/s (cSt), moisture content of 0.097%, and acid number of 0.50 mg-KOH/g.