Cheng, Yoke Wang and Chong, Chi Cheng and Cheng, Chin Kui and Ng, Kim Hoong and Witoon, Thongthai and Juan, Joon Ching (2020) Ethylene production from ethanol dehydration over mesoporous SBA-15 catalyst derived from palm oil clinker waste. Journal of Cleaner Production, 249. ISSN 0959-6526, DOI https://doi.org/10.1016/j.jclepro.2019.119323.
Full text not available from this repository.Abstract
The silica-rich palm oil clinker (POC) from oil palm agroindustry is often dumped in landfill. This work investigated the valorisation of POC into Santa Barbara Amorphous-15 (SBA-15) catalyst, the modulation of its surface acidity, and its application in dehydration of ethanol to ethylene. With commercial SBA-15 SBA-15(Comm.)] as reference, the successful fabrication of POC-derived SBA-15 POC-SBA-15(pH = 3, 5, and 7)] were validated by spectroscopic and microscopic characterisation. From the results of temperature-programmed desorption of ammonia, the SBA-15(Comm.) have high strong acidity while POC-SBA-15 exhibit enriched weak-moderate acidity. For ethanol dehydration over SBA-15 at 200 -400 degrees C, the ethanol conversion (X-C2H5OH) and ethylene selectivity (S-C2H4) rise with temperature. The catalytic activity was ranked as SBA-15(Comm.) < POC-SBA-15(3) < POC-SBA-15(7) < POC-SBA-15(5). Spent catalysts characterisation unanimously confirms the least carbon deposition on POC-SBA-15(5), which subsequently used to study the effect of initial ethanol concentration and liquid hourly space velocity (LHSV). When 99.5 wt% ethanol diluted to 50 wt%, the competitive adsorption between ethanol and water reduces X-C2H5OH but enhances S-C2H4. Further ethanol dilution (<= 30 wt%) deteriorates S-C2H4 following remarkable ethanol steam reforming at elevated temperature (>= 350 degrees C). For 50 wt% ethanol dehydration over POC-SBA-15(5) at 400 degrees C, a greater LHSV furnishes a higher ethanol partial pressure that increases X-C2H5OH but decreases S-C2H4. When LHSV >16 mL/g$h, the saturation of finite active sites with adsorbates renders the drastic declination of X-C2H5OH and S-C2H4. For ethanol dehydration over POCSBA-15(5), the optimal conditions are temperature of 400 degrees C, initial ethanol concentration of 50 wt%, and LHSV of 16 mL/g$h. Fresh POC-SBA-15(5) steadily catalyses the optimal process (73.33% X-C2H5OH and 84.70% S-C2H4) up to 105 h. Meanwhile, regenerated POC-SBA-15(5) achieves a lower catalytic activity (71.95% X-C2H5OH and 81.96% S-C2H4). (C) 2019 Elsevier Ltd. All rights reserved.
| Item Type: | Article |
|---|---|
| Funders: | Ministry of Higher Education (MOHE), Malaysia [RDU170116] |
| Uncontrolled Keywords: | Palm oil clinker; Mesoporous SBA-15; Ethanol dehydration; Ethylene; Surface acidity; Operating conditions |
| Subjects: | Q Science > QD Chemistry |
| Divisions: | Deputy Vice Chancellor (Research & Innovation) Office > Nanotechnology & Catalysis Research Centre |
| Depositing User: | Ms Zaharah Ramly |
| Date Deposited: | 05 Oct 2023 00:41 |
| Last Modified: | 05 Oct 2023 00:41 |
| URI: | http://eprints.um.edu.my/id/eprint/36820 |
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