HIDRORENGKAH KATALITIK MINYAK SAWIT MENJADI FRAKSI BIOFUEL CAIR MENGGUNAKAN KATALIS Cr/ZEOLIT ALAM AKTIF

Gaspar Bao Balabuana, Prof. Dr. rer. nat. Karna Wijaya, M.Eng.

2011 | Tesis | S2 Ilmu Kimia

Telah dipelajari preparasi, karakterisasi dan uji aktivitas katalis Cr/Zeolit alam aktif dalam reaksi hidrorengkah minyak sawit menjadi fraksi biofuel cair. Zeolit alam yang diperoleh dari Klaten diaktivasi dengan asam sulfat 1 M sehingga diperoleh sampel zeolit alam aktif (ZZA). Preparasi katalis dilakukan dengan metode impregnasi larutan garam prekursor Cr(NO3)3.9H2O pada sampel zeolit alam aktif, dilanjutkan dengan kalsinasi, oksidasi, dan reduksi, sehingga diperoleh katalis Cr/Zeolit alam aktif. Karakterisasi katalis meliputi penentuan situs TO4 (T = Si atau Al) dalam zeolit yang diamati dengan spektrometri inframerah (FT-IR) dan situs asam Bronsted-Lewis, penentuan keasaman dengan metode adsorpsi uap basa amoniak dan piridin, kristalinatas katalis dengan metode difraksi sinar-X (XRD), serta porositas katalis dianalisis dengan Surface Area Analyzer. Reaksi hidrorengkah minyak kelapa sawit dilakukan dengan menggunakan reaktor fixed-bed pada suhu 450oC dan laju alir H2 20 mL/menit, pada variasi rasio umpan/katalis 1/1, 2/1 dan 3/1 dengan dilakukan preparasi awal pada minyak kelapa sawit. Analisis produk cair menggunakan kromatografi gas, untuk menghitung fraksi bensin, minyak tanah dan diesel. Hasil penelitian menunjukkan bahwa aktivasi asam dan pengembanan pada sampel zeolit logam dapat meningkatkan keasaman sampel. Sampel Zeolit alam aktif memiliki luas permukaan spesifik 162,46 m2/g, katalis Cr/Zeolit alam aktif 74,54 m2/g. Konversi produk cair tertinggi sebesar 82,05% dihasilkan pada perbandingan umpan/katalis 2/1 dengan preparasi awal umpan melalui reaksi esterifikasi.

Preparation, characterization and activity test of Cr/Activated natural zeolite in hydrocracking of palm oil to liquid biofuels have been examined. The natural zeolite were obtained from Klaten was activated by sulfate acid 1 M so that obtained the activated natural zeolite sample. Catalyst preparation of Cr onto activated natural zeolite was conducted with impregnation method using salt precursor Cr(NO3)3.9H2O followed by calcination, oxidation, and reduction to obtain catalyst Cr/Activated natural zeolite. Catalyst characterization includes determination of the site TO4 (T = Si or Al) in zeolites observed with FT-IR, Bronsted and Lewis acid and catalyst acidity using ammonia and pyridine bases adsorption, crystalinity using X-Ray diffraction (XRD), and catalyst porosity using Surface Area Analyzer. Hydrocracking reaction of palm oil was carried out in a fixed-bed reactor at 450o C and H2 flow rate of 20 mL/minute in feed/catalyst ratio of 1/1, 2/1 and 3/1. Pretreatment of palm oil was conducted by heating, esterification method, or adding with methanol. The liquid product of hydrocracking analyzed by gas chromatography. The research results showed that acid treatment and metal impregnation on to the zeolite sample increased its acidity. The activated natural zeolite and Cr/ Activated natural zeolite samples have specific surface area of 162.46 m2/g and 74.54 m2/g, respectively. The highest conversion of liquid product was 82.05% produced at ratio of feed/catalyst of 2/1 with esterification method in pretreatment of palm oil.

Kata Kunci : Katalis Cr/Zeolit alam aktif, hidrorengkah katalitik, minyak sawit, biofuel.