Ammonium Chloride Activated Klaten Natural Zeolite as A Catalyst of Ethanol Dehydration to Diethyl Ether

ZAIRA ADILA, Prof. Dr. Triyono, S.U.; Prof. Dra. Wega Trisunaryanti, M.S., PhD.Eng.

2022 | Skripsi | S1 KIMIA

Aktivasi zeolit alam Klaten dengan amonium klorida (1 dan 2 M) dalam dan analisis aktivitas katalitiknya telah dilakukan. Tujuan dari penelitian ini antara lain mempelajari pengaruh aktivasi dengan ammonium klorida terhadap karakteristik, aktivitas, dan selektivitas zeolit alam Klaten sebagai katalis dehidrasi etanol untuk menghasilkan dietil eter (DEE). Tiga katalis disintesis dari zeolit alam Klaten (ZA) melalui proses aktivasi dengan amonium klorida 1 dan 2 M selama 24 jam pada temperatur ruang lalu dilanjutkan dengan kalsinasi pada temperatur 500 oC selama 5 jam dengan aliran gas N2 untuk menghasilkan katalis ZA, HZA1, dan HZA2. Karakterisasi katalis dilakukan dengan XRD, SEM-EDX, XRF, SAA, dan keasaman secara gravimetri dan FTIR. Masing-masing katalis digunakan pada reaksi dehidrasi etanol untuk menghasilkan dietil eter dengan variasi temperatur 200, 250, dan 300 oC dan massa katalis 0,1; 0,2; dan 0,4 g. Katalis ZA, HZA1, dan HZA2 terdiri dari mordenite sebanyak 25,21; 32,57; dan 31,31% serta memiliki rasio mol Si/Al sebesar 4,13; 4,03; dan 4,73. Aktivasi dengan amonium klorida menurunkan kandungan logam pada ZA. Katalis HZA1, ukuran kristal dan diameter pori sebesar 2,86 dan 1,77 nm, memiliki luas permukaan (48,32 m2 /g), keasaman total (6,48 mmol/g), dan kestabilan tertinggi karena mengandung situs asam Bronsted (2,75 mmol/g) paling banyak meskipun jumlahnya masih kurang dari situs asam Lewis (3,73 mmol/g). Katalis HZA1 menghasilkan konsentrasi DEE tertinggi sebanyak 2,41% pada temperatur 250 oC dan massa katalis 0,1 g. Katalis HZA1 masih menghasilkan DEE hingga penggunaan kedua dan ketiga sebanyak 2,40 dan 2,61%.

Activation of Klaten natural zeolites by ammonium chloride in 1 and 2 M concentration and their catalytic activity in diethyl ether (DEE) synthesis had been studied. This study aimed to examine the effect of ammonium chloride toward characteristics, activity and selectivity of Klaten natural zeolite as a catalyst in ethanol dehydration to produce diethyl ether. Three catalysts were synthesized from raw Klaten natural zeolite (ZA) by 1 and 2 M ammonium chloride treatment for 24 h at room temperature then followed by calcination at 500 oC for 5 h with N2 gas to produce HZA1 and HZA2. The ZA, HZA1 and HZA2 were characterized by XRD, SEM-EDX, XRF, SAA, and acidity by gravimetry and FTIR. The ZA, HZA1 and HZA2 were used as a catalyst in ethanol dehydration to produce diethyl ether at a temperature of 200, 250 and 300 oC and mass of catalyst 0.1, 0.2 and 0.4 g. The ZA, HZA1 and HZA2 consist of mordenite 25.21, 32.57 and 31.31%, Si/Al mol ratio of 4.13, 4.03 and 4.73 respectively. The ammonium chloride treatment decreased the metal content in ZA. The HZA1 which has crystal size of 2.86 nm showed the highest specific surface area (48.32 m2/g) and total acidity (6.48 mmol/g) also the smallest pore diameter (1.77 nm). Moreover, the HZA1 is the most stable catalyst because it has the highest Bronsted acid site (2.75 mmol/g) although Lewis acid sites (3.73 mmol/g) are still higher. The HZA1 produced the highest diethyl ether yield of 2.41% at temperature of 250 oC and mass of catalyst 0.1 g. Usability test of HZA1 showed that the catalyst can be used until three times and still produced high diethyl ether yield at the second and third run, 2.40 and 2.61% respectively.

Kata Kunci : ammonium chloride, dehydration, diethyl ether, ethanol, zeolite