Konversi lemak itik menjadi biodiesel dengan katalis zeolit alam teraktivasi H2SO4 dan NaOH

KURNIA, Ahmad Taufiq, Akhmad Syoufian, S.Si., Ph.D

2009 | Tesis | S2 Ilmu Kimia

Telah dilakukan penelitian konversi lemak itik menjadi biodiesel menggunakan zeolit alam yang diaktifasi dengan asam sulfat ( H2SO4) 0,1 M dan NaOH. Karakterisasi H-Zeolit meliputi keasaman dengan metode gravimetri, diffraksi sinar X, FT-IR dan Scanning Electron Microscopy ( SEM ). Sebelum reaksi transesterifikasi, dilakukan reaksi esterifikasi lemak itik dengan katalis HZeolit dalam metanol sebagai perlakuan awal lemak itik yang mengandung asam lemak bebas tinggi. Rasio persentase H-Zeolit terhadap media bervariasi, yaitu 1,25 %; 2,50 %; 3,75 % dan 5 %. Reaksi dilanjutkan dengan katalis basa NaOH dalam media metanol. Sebagai pembanding, dilakukan juga perlakuan awal lemak itik dengan asam sulfat 1,25 % sebelum reaksi transesterifikasi terkatalilis basa dengan metode yang sama. Proses esterifikasi dan transesterifikasi dilakukan di dalam reaktor biodiesel dengan temperatur 40 oC selama 4 jam. Biodiesel yang diperoleh dianalisis dengan Gas chromatography – Mass spectroscopy (GCMS), 1H-NMR dan analisis sifat fisiknya dengan metode ASTM Hasil penelitian menunjukkan bahwa aktifasi asam tidak merusak struktur zeolit dan meningkatkan keasaman. Protipe reaktor biodiesel dapat digunakan untuk sintesis biodiesel dari lemak itik. Biodiesel tertinggi dihasilkan pada konsentrasi H-Zeolit 3,75 % (b/b) yaitu 53,01 %

Conversion of duck’s fat into biodiesel using H2SO4 activated natural zeolite catalyst has been carried out. Natural Zeolite was activated by sulfuric acid 1 M. The characterization of H-Zeolit included the acidity was determined by a gravimetric method, X-ray diffractometry, FT-IR and Scanning Electron Microscopy (SEM). Before transesterification reaction, duck’s fat was esterified over H-Zeolite catalyst in methanol medium as a pretreatment for reducing free fatty acid content. H-Zeolit ratio by weight towards fat and methanol was varied, there were 1.25%, 2.50%, 3.75% and 5.00%. The reaction was continued by constant ratio of base catalyst (technical NaOH) in the methanol medium. As comparison, pretreatment of duck’s fat also has been done over 1.25% liquid catalyst used (sulfuric acid), before base catalytic transesterifikasi reaction by the similar method. Esterification and transesterification processes were done in the reactor conducted at temperature 40 °C for 4 hours. Biodiesel was analyzed with Gas Chromatography-Mass Spectroscopy (GC-MS), and 1H-NMR and their physical properties was analyzed using ASTM methods. The research results showed that acidification gave no destruction of zeolite structure and increased its acidity. The prototype biodiesel reactor could be used for biodiesel synthesis from duck’s fat. The highest conversion of biodiesel was 53.01% achieved by H-Zeolite catalyst 3.75% (w/w). Based on the ASTM data, the biodiesel was qualified as diesel fuel and has characters of SNI Biodiesel and automotive diesel fuel.

Kata Kunci : Aktifasi Zeolit alam,Biodiesel,Asam lemak bebas,Lemak itik, Activated Natural Zeolite; Biodiesel; free fatty acid, duck’s fat