Development of Novel Catalyst for Selective Removal of H2S from Natural Gas Stream

Natural gas is one of the major growing sources of energy that substitute other fossil fuels in the next few decades. The increasing demand for energy and the limitation of its conventional sources has set natural gas as energy source that offer a secure and sustainable way for worlds economy in the future Natural gas contains several impurities and should be treated to enhance its quality and purity. One of the significant pollutants in natural gas is the existence of hydrogen sulfide (H2S). It is estimated that the percentage of H2S is in the range of 0-5%. In extreme cases it can be as high as 35% depending on its rock formation, which results in several technological and health drawbacks. There are several technological treatments methods can be employed for removal of H2S from NG. Recent development in NG treatment process showed that hybrid separation processes can be utilized industrially at high efficiency and lower cost compared to the conventional methods. The integration of two or more processes can balance their drawbacks and hence combine the required advantages. Wet oxidation of H2S in aqueous solutions containing oxidative chelates has gained much attention in recent years. This study aims to develop a hybrid catalytic process for selective removal of hydrogen sulfide from natural gas stream. In this process wet oxidation of hydrogen sulfide is achieved based on three phase interaction between HSS, working solution and surface of catalyst. The H2S gas is first absorbed by the working solution, followed by adsorption onto the surface of catalyst and then oxidized into elemental sulfur. The efficiency of the process is therefore depending on the solubility of the H2S in the aqueous solution, adsorption capacity of the catalyst support and the activity of the catalyst itself. The research will begin by a detailed literature review, to select the right catalyst system. The selected catalyst system will be synthesized following a sol-gel catalyst synthesis method. All the synthesized nanocatalyst samples will be characterized for their physical and chemical prosperities according to the ASTM standards. A semi-batch reactor system will be constructed and tested to evaluate the performance of the catalysts. Catalysts will be selected based on their efficient and stable removal of H2S form the simulated natural gas stream. Different characterization techniques will be used to characterize the best performing catalyst.. Kinetic experiments will be performed at different conditions to develop a kinetic reaction model based on given experiments. It is expected to develop a novel catalyst that is being able to reduce hydrogen sulfide from natural gas effectively and selectively. One of the major outcomes from this project is to develop and implement a new technology for gas sweetening. In this regards it is expected to file patents and publish research articles in well-refereed journals. This project will be a vehicle to train the faculty members, researchers and technicians in this important applied research area.