IOSR Journal of Engineering (IOSRJEN) www.iosrjen.org ISSN (e): 2250-3021, ISSN (p): 2278-8719 Vol. 11, Issue 5, May 2021, ||Series -II|| PP 16-21 International organization of Scientific Research 16 | P a g e Modeling of Adiabatic Fixed Bed Reactor for Catalytic Oxidation of Sulphurdioxide to Sulphurtrioxide Ene, Peter Meshack 1 , Adeloye, Olalekan Michael 2 , Cyrus, Aseibichin 3 1,2,3 (Department of Chemical/Petrochemical Engineering, Rivers State University, Port Harcourt, Nigeria.) Received 08 May 2021; Accepted 23 May 2021 ABSTRACT Models for predicting catalytic conversion of SO 2 to SO 3 were developed. The models were developed from the first principle using conservation of mass and energy respectively and the developed model is a set of ordinary differential equation that were solved using ODE 45 solver of MatLab and validated with literature data. The result yielded a minimum percentage absolute error (deviation) between predicted models and literature data of 4.20% and 5.00% for fractional conversion and temperature respectively. These shows that the model developed predicted the output of SO 2 catalytic conversion very closely. The developed models were used to study the effect of process parameters such as fractional conversion (concentration) and temperature (inlet and outlet) along the reactor length for adaiabatic fixed bed reactor at steady state. KEYWORD: Adiabatic Fixed Bed. Steady State modeling, SO 2 , SO 3 , MatLab ODE45 Solver I. INTRODUCTION Sulphurdioxide (SO 2 ) is released into the atmosphere as a result of domestic and industrial activities by the oxidation of sulphur contained in fossil fuels and industrial processes that treat and produce sulphur containing compounds. The catalytic oxidation of sulphurdioxide appears in numerous industrial processes and has a significant environmental impact because of the associated sulphuroxide (SOx) emissions from processes such as burning molten waste elemental sulphur, high SO 2 strength metallurgical off-gases, decomposing spent sulphuric acid catalyst by smelting and roasting ores, crude oil refining. bleaching processes (foodstuffs, sugar, and textiles), papermaking and glass production, fumigation of vessels etc. This is of great concern as its accumulation with other harmful gases leads to greenhouse effect and ozone layer depletion, thus there is need for its reduction in the atmosphere[1] Sulphurdioxide is one of the most deadly gas in the universe and it is released into the atmosphere as a result of domestic and industrial activities. When SO 2 is released in the heart of densely populated areas, it does great damage to the respiratory organs of living entities and most importantly, it is one of the precursors of acid rain that damages buildings and also corrode other physical structures. Hence, there is need to minimize SO 2 release into the atmosphere. Thus, minimizing the release of SO 2 into the atmosphere, a model is developed in predicting its catalytic conversion in an adiabatic fixed bed reactor to produce SO 3 , which is useful in producing some industrial chemicals[2] One common configuration in the industrial practice of a catalytic process is the fixed bed reactor, which consists of stationary solid catalyst particles through which the reacting fluid flows at certain operating conditions. It is most widely used for gas phase reactions in large-scale production. Although the local flow characteristics in such a reactor are really complex, the macroscopic flow pattern can often be approached as plug flow. The analysis of these reactors spans from the micro scale, with the pellet and its pore structure where the phenomena of reaction and diffusion occur, to the macro scale, with the geometry and the characteristics of the reactor bed where the phenomena of heat and mass convection, dispersion, and transfer occur[3] Fixed bed reactor can be classified as adiabatic and non-adiabatic reactor. Adiabatic reactor and non-adiabatic reactor are thermodynamic terms that describe the energy exchange between the system and the surroundings. An adiabatic system exchanges work, but no heat transfer with its surrounding. Thus the wall of an adiabatic reactor are heat opaque; they are insulated: Also, system with no or poor insulation can be adiabatic if any change within them occurs more rapidly than does achieving a new energy equilibrium with their surroundings[4] Therefore, an adiabatic process is a thermodynamic process in which there is no heat transfer into or out of a system and is generally obtained by surrounding the entire system with a strongly insulating material or by carrying out the process so quickly that there is no time for a significant heat transfer to take place. Adiabatic process occurs within a system as a result of transfer of energy to or from the system in the form of work only, and is characterized by an increase in entropy or degree of disorderliness[5] In addition, the importance of SO 3 gas to the chemical industry and the economy at large cannot be quantified, as it is used for the manufacturing of important products and chemicals such as fertilizers, paints, soaps, fibers, crude oil refining, paper production, sulphuric acid, linear Alkyl benzene-sulphonic acid etc. It is extremely hard to find any branch of the economy in which either SO 3 or products made from it are not used[6].