PENGARUH KANDUNGAN DAN URUTAN IMPREGNASI LOGAM Ni DAN/ATAU Pt PADA KARBON TERAKTIVASI MICROWAVE DARI KAYU KELAPA TERHADAP KARAKTER KATALIS PADA HIDRORENGKAH MINYAK NYAMPLUNG (Calophyllum inophyllum L.) MENJADI BIOAVTUR

FENTI VISIAMAH, Prof. Dr. Wega Trisunaryanti, M.S. ;Prof. Dr. Triyono, S.U.

2023 | Tesis | MAGISTER KIMIA

Sintesis katalis Ni dan/atau Pt terimpregnasi pada karbon teraktivasi microwave untuk hidrorengkah minyak nyamplung menjadi bioavtur telah berhasil dilakukan. Karbon aktif dipreparasi dari kayu kelapa menggunakan metode microwave (CWMM), konvensional (CWCC), dan kombinasi (CWCM) dengan CO2 sebagai agen pengaktivasi. Impregnasi Ni dan/atau Pt dilakukan dengan impregnasi basah. Sintesis katalis dengan variasi pengemban karbon aktif menghasilkan 1%Ni/CWCC, 1%Ni/CWCM, dan 1%Ni/CWMM. Pengaruh kandungan logam dipelajari dengan mengimpregnasikan logam Ni atau Pt dengan kadar yang berbeda pada CWMM menghasilkan 5%Ni/CWMM, 1%Pt/CWMM, dan 5%Pt/CWMM. Pengaruh urutan impregnasi Ni dan Pt pada CWMM sebagai katalis bimetal dipelajari pada katalis 2.5%Ni-2.5%Pt/CWMM (Pt terlebih dahulu kemudian Ni), 2.5%Ni2.5%Pt/CWMM (Ni dan Pt secara bersamaan), dan 2.5%Pt-2.5%Ni/CWMM (Ni terlebih dahulu kemudian Pt). Material karbon dan katalis dikarakterisasi dengan FTIR, XRD, SAA, SEM-EDX, TEM, dan uji keasaman. Katalis dipelajari aktivitas dan selektivitasnya terhadap hidrorengkah minyak nyamplung untuk menghasilkan bioavtur, serta dilakukan uji stabilitas dengan pemakaian berulang sebanyak 5 kali running. Produk cair hidrorengkah dianalisis menggunakan GC-MS. Hasil penelitian menunjukkan bahwa CWMM sebagai pengemban terbaik dengan luas permukaan 6,103 m²/g, diameter pori 13,490 nm dan keasaman 0,475 mmol/g. Pengaruh variasi pengemban menunjukkan katalis 1%Ni/CWMM memiliki aktivitas dan selektivitas terbaik dengan hasil produk cair 18,80% b/b dan hidrokarbon bioavtur 15,85% b/b. Impregnasi Ni atau Pt dengan kadar yang lebih tinggi meningkatkan kemungkinan terjadinya aglomerasi yang mengakibatkan menurunnya aktivitas katalitik. Katalis 5%Pt/CWMM memiliki nilai keasaman tertinggi yaitu 1,442 mmol/g dengan total konversi 89,07% b/b. Namun, hasil produk cairnya yaitu 15,60% b/b, merupakan yang terendah dari semua katalis. Aktivitas dan selektivitas katalis terbaik yang dihasilkan berdasarkan urutan impregnasi yaitu 2.5%Ni-2.5%Pt/CWMM>2.5%Ni2.5%Pt/CWMM>2.5%Pt-2.5%Ni/CWMM. Aktivitas dan selektivitas terbaik dicapai oleh katalis 2.5%Ni-2.5%Pt/CWMM yang memiliki luas permukaan 327,466 m²/g, diameter pori 1,063 nm, dan nilai keasaman 1,276 mmol/g, dengan bioavtur yang dihasilkan sebesar 33,10% b/b dan setelah penggunaan kelima menjadi 12,89% b/b.

A Ni and/or Pt catalyst impregnated on microwave-assisted activated carbon was synthesized for hydrocracking Calophyllum inophyllum L. oil into bioavtur. Activated carbon was prepared from coconut wood using microwave (CWMM), conventional (CWCC), and combination (CWCM) methods with CO2 as an activating agent. Impregnation of Ni and/or Pt was conducted by wet impregnation. The synthesis of catalysts with different activated carbon produced 1%Ni/CWCC, 1%Ni/CWCM, and 1%Ni/CWMM. The effect of metal content was studied by impregnating Ni or Pt with different concentrations on CWMM to produce 5%Ni/CWMM, 1%Pt/CWMM, and 5%Pt/CWMM. The effect of Ni and Pt impregnation sequences on CWMM as a bimetallic catalyst was studied on 2.5%Ni-2.5%Pt/CWMM (Pt followed by Ni), 2.5%Ni2.5%Pt/CWMM (Ni and Pt simultaneously), and 2.5%Pt-2.5%Ni/CWMM (Ni followed by Pt). The catalyst and carbon materials were characterized by FTIR, XRD, SAA, SEM-EDX, TEM, and acidity tests. The catalyst's activity and selectivity were investigated by hydrocracking Calophyllum inophyllum L.oil to produce bioavtur. Catalyst reusability was conducted by repeatedly using of the catalyst for 5 times. The hydrocracking liquid product was analyzed using GC-MS. The results showed that CWMM was the best-supporting material, with a surface area of 6.103 m²/g, a pore diameter of 13.490 nm and an acidity of 0.475 mmol/g. The effect of activated carbon variations as a supporting material revealed that 1%Ni/CWMM had the highest activity and selectivity, yielding 18.80% w/w liquid product and 15.85% w/w bioavtur hydrocarbons. Impregnation with high Ni or Pt content increases the possibility of agglomeration, leading to a decrease in catalytic activity. In addition, 5%Pt/CWMM had the highest acidity of 1.442 mmol/g with a total conversion of 89.07% w/w. However, it had the lowest yield of liquid products with 15.60% w/w. The best activity and selectivity based on the impregnation sequence were 2.5%Ni-2.5%Pt/CWMM>2.5%Ni2.5%Pt/CWMM>2.5%Pt-2.5%Ni/CWMM. Thus, the highest catalytic activity and selectivity was achieved by 2.5%Ni-2.5%Pt/CWMM with a surface area of 327.466 m²/g, a pore diameter of 1.063 nm, and an acidity of 1.276 mmol/g. The yield of bioavtur hydrocarbon were 33.10% w/w and decreased to 12.89% w/w after 5 times of catalyst used.

Kata Kunci : bioavtur, hidrorengkah, microwave, karbon aktif, urutan impregnasi