Modifikasi Mordenit dengan Perlakuan HNO3 dan/atau NaOH sebagai Katalis Pada Hydrotreating Alfa-Selulosa Terpirolisis

DESI SURYANI, Prof. Dra. Wega Trisunaryanti, M.Si., Ph.D.M.Eng; Prof.Drs. Karna Wijaya, M.Eng, Dr.rer.nat.

2018 | Skripsi | S1 KIMIA

Telah dilakukan modifikasi mordenit dengan perlakuan HNO3 dan/atau NaOH digunakan sebagai katalis pada hydrotreating alfa-selulosa terpirolisis. Pada penelitian ini digunakan mordenit komersial (HSZ-642NAA) yang digunakan sebagai mordenit kontrol (HM), kemudian mordenit direfluks dengan HNO3 0,1 dan 0,5 M pada temperatur 70 derajat C selama 3 jam dan dihasilkan mordenit AM0,1 dan AM0,5. Mordenit HM, AM0,1 dan AM0,5 diaduk dalam larutan NaOH 0,1 M selama 15 menit pada temperatur 27 derajat C, selanjutnya direfluks dengan NH4Cl 1 M pada temperatur 70 derajat C selama 2 jam dan diperoleh mordenit BHM, BAM0,1 dan BAM0,5. Karakterisasi rasio Si/Al mordenit dianalisis dengan Inductively Coupled Plasma (ICP), keasamannya menggunakan adsorpsi uap NH3 secara gravimetri, kristalinitasnya dengan X-ray Diffraction (XRD), serta analisis karakter pori mordenit BHM, BAM0,1 dan BAM0,5 dengan Gas Sorption Analyzer (GSA). Aktivitas serta selektivitas katalitik mordenit diuji melalui proses hydrotreating alfa-selulosa terpirolisis dengan aliran gas H2 20 mL menit-1 pada temperatur 450 derajat C selama 2 jam dengan rasio berat katalis dan umpan sebesar 1:60, produk cair yang dihasilkan dianalisis menggunakan Chromatography-Mass Spectrometer (GC-MS). Hasil penelitian menunjukkan terdapat kenaikan rasio Si/Al dari mordenit seiring dengan penurunan kristalinitas setelah diberi perlakuan HNO3 dan/atau NaOH. Keasaman mordenit mengalami penurunan seiring dengan kenaikan rasio Si/Al, kecuali AM0,1. Diameter pori rata-rata mordenit BHM, BAM0,1 dan BAM0,5 berturut-turut sebesar 2,96; 3,34 dan 4,53 nm. Mordenit BAM0,1 menunjukkan aktivitas katalitik tertinggi dalam menghasilkan fraksi cair sebesar 64,04 % (b/b). Mordenit BAM0,5 menunjukkan selektivitas katalitik terbaik karena menghasilkan 1-pentena 0,44% (b/b); 2-heptuna 2,75% (b/b) serta 1-propanol 3,05% (b/b) dari proses hydrotreating alfa-selulosa terpirolisis.

Modification of mordenite had been performed with HNO3 and/or NaOH used for a catalyst in the hydrotreating of pyrolyzed alfa-cellulose. In this research, commercial mordenite (HSZ-642NAA) was used as mordenite control (HM), then the mordenite was refluxed in 0.1 and 0.5 M of HNO3 at 70 degree C for 3 h and AM0,1 and AM0,5 were produced. The HM, AM0,1 and AM0,5 mordenites were stirred in 0.1 M of NaOH for 15 minutes at temperature 27 degree C, then refluxed in 1 M NH4Cl at 70 degree C for 2 h and BHM, BAM0,1 and BAM0,5 mordenites were obtained. The characterization of Si/Al ratio of mordenites was analyzed by using Inductively Coupled Plasma (ICP), the acidity were by using ammonium vapour adsorption by gravimetry, the crystallinity by using X-ray Diffraction (XRD), and the analysis of mordenite pore character of BHM, BAM0,1, and BAM0,5 were analyzed by using Gas Sorption Analyzed (GSA). Catalytic activity and selectivity of the mordenites were evaluated in the hydrotreating of pyrolyzed alfa-cellulose with 20 mL minute-1 H2 gas flow at 450 degree C for 2 h with the weight ratio of catalyst and feed was 1:60. The liquid products were analyzed using Chromatography-Mass Spectrometer (GC-MS). The results of the study showed that there was an increase in the Si/Al ratio of mordenite along with the decrease in crystallinity after being treated with HNO3 and/or NaOH. The acidity of mordenites decreased along with the increase of Si/Al rasio, except for the AM0,1 mordenite. The average pore diameter of BHM, BAM0,1 and BAM0,5 mordenites were 2.96; 3.34 and 4.53 nm, respectively. The BAM0,1 mordenite showed the highest catalytic activity in generating liquid fraction (64.04 wt%). The BAM0,5 mordenite showed the best catalytic selectivity because it produces 1-pentene 0.44 (wt%); 2-heptune 2.75 (wt%) and 1-propanol 3.05 (wt%) from the hydrotreating process of pyrolyzed alfa-cellulose.

Kata Kunci : Kata kunci: hydrotreating, mordenit, perlakuan HNO3, perlakuan NaOH, struktur mesopori, Keywords: hydrotreating, mordenite, HNO3 treatment, NaOH treatment, mesoporous structure.