Sintesis dan Karakterisasi Biodiesel dari Minyak Jelantah dengan Katalis Heterogen Cangkang Telur Burung Puyuh-SiO2

Abstract

Minyak jelantah dan cangkang telur burung puyuh berpotensi dimanfaatkan sebagai bahan baku biodiesel dan prekursor katalis heterogen. Penelitian ini bertujuan mengevaluasi pengaruh suhu kalsinasi katalis CaO-SiO2 berbasis cangkang telur burung puyuh dan suhu transesterifikasi terhadap rendemen serta mutu biodiesel. Katalis disintesis melalui impregnasi basah dengan SiO2 20% (b/b) dan KOH 11% (b/b), kemudian dikalsinasi pada 600, 700, dan 800 °C. Reaksi transesterifikasi minyak jelantah dilakukan pada 50, 60, dan 70 °C selama 120 menit menggunakan rasio molar minyak:metanol 1:9 dan katalis 5% (b/b). Katalis dikarakterisasi menggunakan SEM, FTIR, XRD, dan BET, sedangkan biodiesel diuji berdasarkan rendemen, densitas, dan bilangan asam. Kondisi optimum diperoleh pada kalsinasi 800 °C dan transesterifikasi 60 °C, menghasilkan rendemen 87,80%, densitas 886,70 kg/m³, dan bilangan asam 0,2731 mg KOH/g. Densitas dan bilangan asam tersebut memenuhi batas SNI 7182:2015.

Waste cooking oil and quail eggshells have the potential to be used as raw materials for biodiesel and precursors for heterogeneous catalysts. This study aims to evaluate the effect of calcination temperature of quail eggshell-based CaO-SiO2 catalyst and transesterification temperature on biodiesel yield and quality. The catalyst was synthesized by wet impregnation with 20% (w/w) SiO2 and 11% (w/w) KOH, then calcined at 600, 700, and 800 °C. The transesterification reaction of waste cooking oil was carried out at 50, 60, and 70 °C for 120 minutes using an oil:methanol molar ratio of 1:9 and 5% (w/w) catalyst. The catalyst was characterized using SEM, FTIR, XRD, and BET, while the biodiesel was tested based on yield, density, and acid number. The optimum conditions were obtained at 800 °C calcination and 60 °C transesterification, resulting in a yield of 87.80%, a density of 886.70 kg/m³, and an acid number of 0.2722 mg KOH/g. These density and acid number meet the limits of SNI 7182:2015.