The Preparation Of Methane Cracking Catalyst For Hydrogen Production And Its Performance And Simulation Studies

As oil resources drying up, such problems as environmental pollution and the greenhouse effect intensifying, the research and development of the clean energy represented by hydrogen has been paid more attention. Besides the natural gas contains a lot of methane, the bottom of the sea contains a large number of flammable ice, and the biomass production of biogas are also contain large amounts of methane. Therefore, the prospect of hydrogen production with methane as raw material is considerable. Based on the literature review, the preparation and modification of catalyst for hydrogen production from methane by nickel based catalyst was studied, in order to solve the problem that the catalyst deactivation caused by the carbon deposition and keep the activity of the catalyst. To this end, on the basis of our previous studies, the paper selected different catalysts and studied the impact of the effect of carbon deposition on the catalyst under different conditions. We have done the following work:(1) In a fixed bed reactor, methane is studied with the different catalysts, namely activated carbon, nickel-based catalysts prepared by impregnation method (Ni-load), nickel-based catalysts 65%Ni-10%Cu-25%SiO2 prepared by sol-gel method(Ni-gel). The effects of temperature, the ratio of material and Ni-gel catalyst and activated carbon mixing ratio on the performance of the catalysts were studied respectively. The experimental results show that the impregnation of Ni/activated carbon catalyst can reach a higher methane conversion rate in 650℃, but only can continue a short time and catalyst deactivated quickly, sol-gel prepared Ni-gel catalyst has higher reactivity and good continuity. According to our research, Ni-gel catalyst and active carbon mixed in certain proportion can improve the dispersion of catalyst, relieve the sintering phenomenon and accelerate the reduction rate of the catalyst.(2) The steam reforming of methane is simulated by ASPENPLUS and it provides theory for experimental steam reforming of methane.In the simulation of methane steam reforming, the proper temperature and pressure are 1100℃ and ordinary pressure. With increasing S/C, the volume percent of H2 and CO2 increase while those of CH4 and CO decrease.(3) In order to increase the rate of the pyrolysis of methane and elimination carbon deposition, we adding Fe2O3 to Ni-gel catalyst and dissolved into the water vapor to the reaction system, and by adjusting the addition amount of water vapor to seek the optimum water/carbon ratio. On this basis, compared with the current industrial methane hydrogen cracking catalyst, the results showed that:Ni-gel/Fe2O3 catalytic cracking of methane was 98.88 percent, coke rate of minimum 0.11 (Wt/%), industrial catalyst Z118-4Y under laboratory conditions did not show good activity on the catalytic decomposition of methane, cleavage rate was 53.65%.