Optimization of nickel catalyst loading in Ni/γAl2O3 for producing carbon nanotubes through natural gas decomposition

Abstract

Carbon nanotubes can be produced at high quality through hydrocarbon catalytic decomposition. In addition, hydrogen can be produced as a valuable byproduct at a competitive price. In this article, the loading of the active phase in the decomposition catalyst is optimized using natural gas as a widely available hydrocarbon. Natural gas decomposition was investigated using different nickel loadings. Natural gas decomposition, as a widely available hydrocarbon, is investigated by manipulating nickel loading to optimize the loading of the active phase in the decomposition catalyst.Optimizing the catalyst loading can achieve higher quality and yield of carbon nanotube. In addition, a higher carbon nanotube yield will maximize hydrogen production. Increasing the quality of produced carbon and the amount of hydrogen will improve the overall process economics. Nickel is a highly active catalyst for natural gas decomposition and has a higher carbon affinity compared to other metallic catalysts. Different nickel loadings were tested for natural gas decomposition. Optimization was used to calculate the optimum nickel loading based on the experimental results. The optimum nickel loading over alumina was 12.5%. The economic analysis of the process indicated that the optimum nickel loading is 30%.