Kajian pemanfaatan reverse flow reactor untuk oksidasi katalitik uap bensin
DOI:
https://doi.org/10.5614/jtki.2011.10.1.4Abstract
Study of utilization of reverse flow reactor for the catalytic oxidation of gasoline vapor Catalytic oxidation of gasoline vapor is one of methods to reduce the gasoline vapor emission at fuel station. This reaction is exothermic with large heat of reaction, so that the heat released can be used for heating the feed gas, leading to auto thermal condition.. The auto thermal conditions with low feed concentration, like gasoline vapor emission, can be achieved by using a reverse-flow reactor (RFR), a kind of fixed bed reactor in which flow direction is periodically changed. The objective of this research is to develop the using of a RFR to reduce the gasoline vapor emissions at fuel station, based on simulations using FlexPDE version 6 and later used as the basis for the experimental development. The model of RFR was developed, by using iso-octane as a model component. The simulation consists of: (1) RFR with one way direction, which was used as the basis for the determination of RFR operating conditions and (2) RFR at current start-up conditions. The simulations were conducted using a software package FlexPDE version 6. The kinetic parameters and physical properties were taken from literature. The simulation results of the RFR at one way direction show that catalytic oxidation of gasoline vapor can conducted best at temperature of 773 K, while the RFR shows the accumulation of heat in the reactor bed that can be utilized for process start-up. Time to reach 100% conversion of gasoline for reverse flow operation mode is faster than one way operation mode. Thus the operation of gasoline emission catalytic oxidation reaction in reverse flow reactor can be developed experimentally.
Keywords: Dynamic reactor, Catalytic oxidation
Abstrak
Oksidasi katalitik uap bensin adalah salah satu cara untuk mengurangi emisi uap bensin di stasiun pengisian bahan bakar umum. Reaksi ini adalah reaksi eksotermik, sehingga panas reaksi yang timbul dapat dimanfaatkan untuk memanaskan umpan agar reaktor dapat berperilaku ototermal. Kondisi ototermal dengan umpan emisi uap bensin yang berkonsentrasi rendah dapat tercapai dengan menggunakan reverse flow reactor (RFR), yaitu reaktor unggun tetap yang arah alirannya diubah secara periodik. Tujuan kajian ini adalah untuk mengkaji pemanfaatan RFR untuk menurunkan emisi uap bensin di SPBU, berdasarkan simulasi menggunakan FlexPDE versi 6 dan nantinya digunakan sebagai dasar pengembangan secara eksperimental. Model RFR dikembangkan dengan menggunakan iso-oktana sebagai komponen model. Simulasi terdiri dari (1) simulasi RFR satu arah, yang digunakan sebagai dasar penentuan kondisi operasi RFR dan (2) simulasi RFR dengan konfigurasi start-up tertentu. Parameter kinetika dan sifat–sifat fisik yang diperlukan diambil dari literatur. Hasil simulasi RFR satu arah menunjukkan bahwa reaksi oksidasi katalitik uap bensin dapat terselenggara dengan baik pada suhu 773 K, sedangkan simulasi RFR kondisi aliran bolak-balik menunjukkan adanya akumulasi panas di unggun reaktor yang dapat dimanfaatkan saat proses start-up. Waktu untuk mencapai konversi 100% untuk simulasi mode operasi bolak-balik lebih cepat daripada mode operasi satu arah. Dengan demikian penyelenggaraan reaksi oksidasi katalitik emis uap bensin di reverse flow reactor secara eksperimental dapat dikembangkan.
Kata Kunci: Reaktor dinamik, Oksidasi katalitik
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