I need to know if it's possible to do the sabatier reaction to produce methane without catalyst, and the temperature that would require. The temperature must be higher (than with catalyst) due to the higher activation energy, right?
Sabatier reaction:
CO2 + 4H2 CH4 + 2H2O
Hi,
Sabatier reaction is a catalytic method for conversion of CO2 to CH4 by the definition. A very wide catalytic system is available to operate this transformation. A review of the materials and their performances has been presented together with some industrial applications in the following link.
https://link.springer.com/chapter/10.1007/978-1-4471-5119-7_8
However, if you mean catalyst-free conversion of CO2 to methane gas, as far as I know, there is no feasible method for that and if there is any, it would probably need very high temperatures.
Dear Sergio Gonzalez ,
By performing simple chemical equilibrium analysis, it can be shown that the amount of CH4 produced decreased drastically with increase in temperature (less than 10 % by volume at equilibrium temp. of 900 K (initial temperature of 400 K ). As overall conversion process is exothermic with high activation energy, this reaction is not possible without a catalyst.
A significant challenge with managing the Sabatier reaction on the commercial scale would be the control of the reaction exotherm. To understand how this might be achieved, take a look at the flowsheets for the SNG process (Substitute Natural Gas). These take syngas (H2/CO/CO2) from a gasifier and methanate the CO/CO2 to make a CH4 rich gas using multiple stage methanation with inter-cooling and gas recycle.
Any reaction can be carried out without a catalyst, the question is what the conversion will be. Unfortunately, it can be expected to be very small. There is another problem here. The reaction is not only reversible but also exothermic. Thus, an increase in temperature will shift the equilibrium to the left, which further reduces the conversion.
Sabatier reaction is a process that produces water and methane by a reaction of hydrogen with carbon dioxide.Reaction is catalyzed by Ni catalyst.