International Journal Of Scientific Research And Education ||Volume||3||Issue||9||Pages-4485-4494||October-2015|| ISSN (e): 2321-7545 Website: http://ijsae.in DOI: http://dx.doi.org/10.18535/ijsre/v3i10.01 Minister E. Obonukut et al ISRE Volume 3 Issue 10 October 2015 Page 4485 Study of The Contribution of Carbon Iv And Carbon II Oxides in Methanol Synthesis With Modified Kinetic Model Authors Minister E. Obonukut 1 , Etim N. Bassey 2 , Benjamin R. Etuk 3 1,3 Department of Chemical and Petroleum Engineering, University of Uyo, P.M.B. 1017, Uyo, Nigeria. 2 Department of Chemical/Petrochemical Engineering, Akwa Ibom State University, Ikot Akpaden, Nigeria E-mail: minister024life@yahoo.com; Tel:+2348026255655 ABSTRACT The objective of this work was the simulation of methanol production process using a modified kinetic model to study the effect of reaction conditions on the relative contribution of Carbon II and Carbon IV oxides in methanol synthesis. The results showed that Carbon II oxide hydrogenation decreased as percentage of Carbon IV oxide increased and vice-versa. However it was observed that no generalizations could be made regarding the main carbon source in methanol but that the pathway of contribution from CO/CO 2 hydrogenation depends on process/reaction conditions. It is recommended that for improved process design, there is the need to carefully interpret experimental data and extrapolate results from low pressure/low conversion to high pressure/high conversion laboratory conditions. Keywords: Methanol, Natural gas, Kinetic Models, Modified Model, Simulation, INTRODUCTION A number of kinetic models for methanol synthesis have been proposed in the literature (Natta, et al., 1955, Bakemeier, et al., 1970, Leonov, et al., 1973, Klier, et al.,1982, Villa, et al., 1985, Graaf, et al., 1988, McNeil, et al., 1989, Skrzypek et al., 1991, Askgaard, et al.,1995, Bussche, et al., 1996, Kubota, et al., 2001, Setinc and Levec, 2001, Rozovskii and Lin, 2003, Lim, et al., 2009). One of the major concerns has been the role of CO and CO 2 in methanol production. Initial kinetic studies on methanol synthesis by Natta et al. (1955) and Leonov, et al.(1973) considered only CO and H 2 as the main reactants and neglected any contribution from CO 2 . Later, Klier, et al. (1982) showed that methanol was mainly formed from CO and H 2 that adsorbed on the catalyst and CO 2 acted only as a promoter and not as a main reactant. They also suggested that methanol production rate was maximum at a CO 2 /CO ratio of 2:28 which was governed by a balance between the promoting effect of CO 2 and the retarding effect due to strong adsorption of CO 2 . In another study, Liu, et al. (1985) conducted initial rate experiments in a batch reactor to determine the effect of feed composition on methanol production rate and obtained conflicting results. Furthermore, Sahibzada, et al.(1998) showed that the intrinsic rate of CO 2 hydrogenation was twenty times faster than CO hydrogenation and at CO 2 greater than 1%, it was the main source of methanol production. They reported that methanol formation rate increased linearly with increase in CO 2 concentration in the absence of products. Establishing the role of CO 2 in methanol production, Ostrovskii, (2002) studied methanol synthesis mechanism on Cu/Zn containing catalyst under a wide range of experimental conditions and showed that CO 2 was the principal source of methanol production.