Hydrogen production advantages

A typical reactor operates at 600—900°C with no catalyst and a residence time of 10—12 s. It produces a 92—93% yield of carbon tetrachloride and tetrachloroethylene, based on the chlorine input. The principal steps in the process include (/) chlorination of the hydrocarbon (2) quenching of reactor effluents 3) separation of hydrogen chloride and chlorine (4) recycling of chlorine to the reactor and (i) distillation to separate reaction products from the hydrogen chloride by-product. Advantages of this process include the use of cheap raw materials, flexibiUty of the ratios of carbon tetrachloride and tetrachloroethylene produced, and utilization of waste chlorinated residues that are used as a feedstock to the reactor. The hydrogen chloride by-product can be recycled to an oxychlorination unit (30) or sold as anhydrous or aqueous hydrogen chloride. 

Figure 8-1. Energy recovery process taking advantage of excess hydrogen production.

Saxe M., Alvfors P., Advantages of integration with industry for electrolytic hydrogen production, Energy, 32(1), 42-50,2007. 

Long-term aim of our project is the construction of a biomolecular device for hydrogen production in combination with light-driven water-splitting as it occurs in the natural process of photosynthesis in plants. Such a semiartificial device should combine the best suited components found in various native systems which - up to now - cannot be found in an individual native system due to incompatibilities and/or different origin (pro- and eukaryotic, meso- and thermophilic, aerobic - anaerobic environment). Advantage of such a system is... 

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