How to produce hydrogen from fossil fuels without CO2 emission
Abstract
Fossil fuels (oil and natural gas) will remain the dominant source for hydrogen production in the next few decades. Present-day processes for the production of hydrogen from hydrocarbons (steam conversion and partial oxidation) are accompanied by the formation of CO2, which is released into the atmosphere. Another possibility is of thermal or thermocatalytic decomposition of natural gas with the production of hydrogen and carbon. The process is technologically simple and economically suitable and makes it possible to use not only natural gas, but also light distilliates and even crude oil and residual oil. The carbon formed may be stored for future use. Assuming that the problem of the production of cheap hydrogen will be solved, then pure carbon can be converted to hydrocarbons and used as a petrochemical feedstock. Thus, it will become possible to relieve the fossil hydrocarbon depletion problem. The thermocatalytic decomposition of methane is discussed in the present paper, as well as the perspectives of carbon utilization.
References (8)
- I. Cherny
Production of Feedstock for Petrochemical Synthesis
(1983) - M. Steinberg et al.
Hydrogen Energy Progress VII
- Yu. Zhorov
Thermodynamics of Chemical Processes
(1985) - M. Andier et al.
Carbon
(1985)
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