Penghasilan asid akrilik dengan menggunakan gliserol perlu dikaji dan dioptimumkan supaya hasil dan kualiti asid akrilik akan terjamin sebelum pelaksanaannya dalam skala industri. Dengan kewujudan perisian simulasi seperti Aspen Plus, proses tertentu dapat disimulasi dan dioptimumkan dengan ciri-ciri produk akhir yang dikehendaki. Walau bagaimanapun, wujudnya ketidakpastian berkenaan keadaan tindak balas optimum bagi menghasilkan asid akrilik yang maksimum. Dalam kajian ini, Aspen Plus digunakan untuk mensimulasi dan mengoptimumkan reaktor dehidrasi katil tetap aliran berterusan (PFR) di mana glycerol bertindak balas atas pemangkin zeolite, ZSM-5 untuk menghasilkan akrolin serta produk sampingan seperti asetaldehid, etena, karbon monoksida, hidrogen dan kok. Keputusan simulasi dibandingkan dengan keputusan yang diperolehi dalam literatur dan didapati bahawa keputusan simulasi yang diperolehi oleh Aspen Plus boleh diterima dengan penukaran dan hasil purata kesilapan sebanyak 4.84% dan 26.25%. Seterusnya, analisis sensitiviti terhadap model reaktor RPLUG tersebut menunjukkan bahawa suhu reaktor, tekanan reaktor dan kepekatan gliserol mempunyai kesan yang jelas terhadap penukaran gliserol dan hasil akrolin. Penukaran glycerol didapati meningkat dengan suhu dan tekanan reaktor tetapi menurun dengan peningkatan WHSV dan kepekatan gliserol. Manakala, hasil acrolein pula meningkat dengan peningkatan suhu reactor sehingga 420°C, WHSV dan kepekatan gliserol sehingga 60%. Akhir sekali, pengoptimuman model reactor menunjukkan bahawa hasil acrolein maksimum yang boleh dicapai ialah 42.85% pada keadaan optimum iaitu suhu reaktor 450.78°C, tekanan 1 bar dan kepekatan gliserol 60%.
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The production of acrylic acid using glycerol feedstock is gaining importance worldwide and thus the process needs to be studied and optimized fully so that the yield and quality of acrylic acid are assured before its implementation in industrial scale. With the development of simulating software such as Aspen Plus, it is possible to simulate and optimize a process with desired end-product characteristics. However, there is no fixed idea on the optimum reaction conditions to produce maximum yield of acrylic acid. In this work, Aspen Plus was used to simulate and optimize an isothermal fixed bed plug flow dehydration reactor where glycerol was dehydrated into acrolein and side-products such as acetaldehyde, ethylene, carbon monoxide, hydrogen and coke in the presence of ZSM-5 zeolite catalyst. The simulation results obtained were first compared with that from literature. The simulated results obtained by Aspen Plus showed that it is acceptable since the simulation values obeyed that of the literature with an average conversion and yield errors of 4.84% and 26.25% respectively. Sensitivity analysis on the same RPLUG reactor model showed that reactor temperature, pressure and glycerol concentration had significant effects on glycerol conversion and acrolein yield. The glycerol conversion was found to increase with reactor temperature and pressure but decreased with WHSV and glycerol concentration. Meanwhile, acrolein yield increased with the rise in reactor temperature till 420°C, WHSV and glycerol concentration up to 60 wt%. Lastly, optimization study on the reactor model resulted in maximum acrolein yield of 42.85% which is achieved at optimum variables of 450.78°C, 1 bar and 60 wt% glycerol concentration.
Simulation and optimization of dehydration reactor in acrylic acid production using glycerol / Belinda Anne Xavier