PREPARATION OF COBALT-SUPPORTED-SBA-15 CATALYSTS BY WET AND CO-IMPREGNATION METHODS FOR HYDROTREATING OF PYROLYZED ALPHA CELLULOSE

ELIZABETH SELIA N, Prof. Dr. Triyono, S. U.; Prof. Dra. Wega Trisunaryanti, M.S., Ph.D.Eng.

2018 | Skripsi | S1 KIMIA

Pembuatan katalis kobalt yang diembankan pada SBA-15 telah dilakukan. Kobalt di impregnasi pada SBA-15 menggunakan Co(NO3)2.6H2O sebagai garam precursor pada pelarut air untuk metode impregnasi basah. Metode ko-impregnasi dilakukan dengan cara menambahkan etilen glikol pada larutan Co(NO3)2.6H2O dengan rasio molar (Co:EG) 1:1 dan dicampur dengan SBA-15. Sampel Co/SBA-15 yang telah disintesis lalu dikalsinasi pada suhu 500 °C selama 5 jam, menghasilkan katalis CoO/SBA-15c dan CoO/SBA-15w, dilanjutkan dengan reduksi menggunakan gas H2 pada suhu 400 °C selama 3 jam dan menghasilkan katalis Co/SBA-15c dan Co/SBA-15w. Katalis-katais tersebut dikarakterisasi menggunakan adsorpsi NH3 (total situs asam), Spektrofotometer Serapan Atom (SSA), X-Ray Diffractometer (XRD), Transmission Electron Microscope (TEM), dan Gas Sorption Analyzer (GSA). Katalis yang telah dibuat digunakan untuk hydrotreating α-selulosa terpirolisis pada reaktor semi-batch pada suhu 450 °C selama 2 jam menggunakan aliran gas H2 (20 cm3 min-1). Kinetika pembentukan produk cair pada hydrotreating α-selulosa terpirolisis telah dipelajari. Hasil penelitian menunjukan bahwa katalis Co/SBA-15c merupakan katalis dengan performa terbaik dibanding katalis lainnya dengan keasaman sebesar 7,42 mmol g-1; kandungan Co sebesar 7,97%; luas area spesifik sebesar 432,263 m2 g-1; konversi produk cair sebesar 70,37%. Menggunakan Co/SBA-15w terdeteksi keasaman sebesar 6,33 mmol g-1; kandungan Co sebesar 6,43%; luas area spesifik sebesar 337,713 m2 g-1; konversi produk cair sebesar 72,72%. Studi kinetika menunjukan bahwa pembenukan produk cair pada hydrotreating α-selulosa terpirolisis menggunakan orde pertama dengan konstanta laju (k) sebesar 0,0095 min-1.

Preparation of cobalt supported on SBA-15 catalysts had been done. Cobalt was impregnated on SBA-15 by the wet impregnation method using Co(NO3)2.6H2O as a salt precursor in aqueous solution. For the co-impregnation method, ethylene glycol (EG) was added into the Co(NO3)2.6H2O solution with a molar ratio (Co: EG) of 1:1 and was mixed with SBA-15. The synthesized Co/SBA-15 was calcined at 500 °C for 5 hours to produce CoO/SBA-15c and CoO/SBA-15w catalysts, followed by reduction by H2 gas at 400 °C for 3 hours and producing Co/SBA-15c and Co/SBA-15w catalyst. The catalysts were characterized using NH3 adsorption analyzer, Atomic Absorption Spectrophotometer (AAS), X-Ray Diffractometer (XRD), Transmission Electron Microscope (TEM), and Gas Sorption Analyzer (GSA). The prepared catalysts were used for hydrotreating of pyrolyzed α-cellulose in the semi-batch reactor at 450 °C for 2 hours under H2 gas stream (20 cm3 min-1). Kinetics of liquid production in the hydrotreating of pyrolyzed α-cellulose using Co/SBA-15w catalyst had been studied. The results showed that Co/SBA-15c has the best catalytic performance compared to the other catalysts with the acidity of 7.42 mmole g-1; Co content of 7.97%; specific surface area of 432.263 m2 g-1; conversion of liquid product of 70.37%. On the other hand, the Co/SBA-15w has the acidity of 6.33 mmole g-1; Co content of 6.43%; specific surface area of 337.713 m2 g-1; conversion of liquid product of 72.72%. Kinetic study showed that the formation of liquid product from hydrotreating of pyrolyzed α-cellulose followed the first order model with a rate constant (k) of 0.0095 min-1.

Kata Kunci : Cobalt, SBA-15, Alpha cellulose, Pyrolysis, and Hydrotreating