Abbas Ghareghashi - Department of Chemical Engineering, University of Sistan and Baluchestan, Zahedan 98164-161, Iran
Farhad Shahraki - Department of Chemical Engineering, University of Sistan and Baluchestan, Zahedan 98164-161, Iran
Kiyanoosh Razzaghi - Department of Chemical Engineering, University of Sistan and Baluchestan, Zahedan 98164-161, Iran
Sattar Ghader - Department of Chemical Engineering, College of Engineering, Shahid Bahonar University of Kerman, Kerman, Iran

This work proposes a one dimensional heterogeneous model to analyze the performance of coupling of Fischer–Tropsch synthesis (FTS) reactors with a fixed-bed reactor which is combined with an oxidative coupling of methane (OCM) over La2O3/CaO catalyst in fixed bed reactor. In the new concept, the natural gas is converted to FT products in two catalytic reactors. The first reactor is OCM, covering a wide range of reaction conditions (1 < pO2 < 20 kPa, 10 < pCH4 < 95 kPa, 700 < T < 955 °C, 0.76 ≤ mCat/VSTP ≤ 250 kg.s/m3) while the second reactor is FT and it convert output synthesis gas of OCM to heavy hydrocarbons. The parameters studied were methane to oxygen (CH4/O2) ratio, temperature, and dilution effect of N2 in the feed. Yield increased with the temperature and a maximum value of yield was obtained at 1103K. High CH4/O2 ratio favored the FT reaction but reduced the yield of ethane. The presence of inert N2 gas in feed gave negligible effect to the yield in the process. Increase of contact time (decrease of feed velocity) has low impact on gasoline yield. Results showed an enhancement in the gasoline yield along the proposed concept.

Fischer–Tropsch, oxidative coupling of methane, contact time effect, feed velocity