Penggunaan Katalis Nikel Fosfida Berpenyangga Zeolit Alam untuk Optimasi Reaksi Esterifikasi Distilat Asam Lemak Sawit menjadi Biodiesel menggunakan Responce Surface Methodology-Box Behnken Design

Abstract

<p><strong>ABSTRAK. </strong>Biodiesel merupakan <em>biofuel</em> generasi pertama, bersifat terbarukan, dan ramah lingkungan yang dapat menggantikan bahan bakar diesel. Bahan bakunya dapat berupa distilat asam lemak sawit (DALMS) yang merupakan produk samping pengolahan minyak sawit mentah, memiliki kadar asam lemak tinggi dan bersifat <em>nonedible</em>. Sintesis biodiesel dari DALMS dilakukan melalui reaksi esterifikasi menggunakan katalis nikel fosfida berpenyangga zeolit alam (NiP/Za). Tujuan penelitian ini adalah menentukan karakteristik katalis dan kondisi optimum esterifkasi DALMS menjadi biodiesel menggunakan <em>Response Surface Methodology-Box Behnken Design </em>(RSM-BBD). Zeolit alam diberi perlakuan desilikasi dan aktivasi serta katalis disintesis dengan impregnasi basah. Esterifikasi dilakukan pada waktu 2 – 4 jam, suhu 45 – 65 ℃, konsentrasi katalis 5% – 15% (b/b). Hasil karakterisasi menunjukkan bahwa katalis memiliki fase kristal Ni<sub>2</sub>P dengan munculnya puncak pada 2θ: 40,5; 44,5; dan 47,21<sup>o</sup>, ukuran kristal 28,64 nm, luas permukaan 35,577 m<sup>2</sup>/g, volume pori 0,094 cc/g, dan diameter pori 3,8306 nm. Parameter waktu dan suhu berpengaruh signifikan terhadap konversi. Kondisi optimum esterifikasi DALMS menjadi biodiesel didapatkan pada suhu 45 ℃, waktu 4 jam, dan konsentrasi katalis 6% dengan konversi 4,67%.</p><table width="100%" border="0" cellspacing="0" cellpadding="0"><tbody><tr><td valign="top" width="82%"><p><strong>ABSTRACT. <em>The use of Natural Zeolite-Supported Nickel Phosphide Catalyst to Optimize the Esterification Reaction of Palm Fatty Acid Distillate into Biodiesel using Response Surface Methodology-Box Behnken Design. </em></strong>Biodiesel is a renewable and environmentally friendly first-generation biofuel that can replace diesel fuel. The raw material can be palm fatty acid distillate (DALMS), a by-product of crude palm oil processing, which has a high fatty acid content and is nonedible. An activated natural zeolite-supported nickel phosphide catalyst (NiP/NZ) makes the esterification reaction easier, which turns DALMS into biodiesel. This study aimed to determine the characteristics of the catalyst and the optimum conditions for the esterification of PFAD into biodiesel using the Response Surface Methodology-Box Behnken Design (RSM-BBD). Natural zeolite was desilicated and activated. Then, the catalyst was synthesized by wet impregnation. Esterification was performed for 2 ‒ 4 h at a temperature of 45 – 65 ℃ and a catalyst dosage of 5% – 15% (w/w). The tests revealed that the catalyst consists of Ni<sub>2</sub>P crystals, exhibiting diffraction peaks at 2θ 40.5, 44.5, and 47.21°. The crystal size is 28.64 nm and the catalyst has a surface area of 35.577 m<sup>2</sup>/g, a pore volume of 0.094 cc/g, and a pore diameter of 3.8306 nm. Time and temperature parameters significantly affected the conversion of DALMS. The optimum condition for DALMS esterification into biodiesel was obtained at 45 ℃, 4 h, and 6% catalyst concentration with 4.67% conversion.<strong></strong></p></td></tr></tbody></table>