Name of Reaction Product

Steam Reformation Syngas

Steam Reformation Syngas

Partial Oxidation Syngas

Steam Reformation Syngas

Water Gas Shift

-92 kcal/mole Combustion

Hydrogen Energy

-205 kcal/mole Combustion Energy

-23 kcal/mole Methanol Synthesis Methanol

methanol proceeds just as it would with coal. Again, this is all strictly tried-and-true nineteenth-century chemical engineering.

A more modern way would be to use a special catalyst to oxidize methane directly into methanol. This saves a process step and thereby cuts costs. A number of such direct oxidation methanol plants are currently under construction.

Biomass, which is primarily cellulose, can also be used to make methanol. Cellulose is a complex long-chain molecule, with an approximate formula of C4H603, with small amounts of nitrogen, traces of sulfur, and a few other odds and ends mixed in. Again, the strategy is simply to turn it into synthesis gas by reaction with steam, using heat provided by burning a minority of the material to drive the conversion of the rest.

Once we have the syngas, the rest of the process follows the same path as that needed to convert coal or natural gas. And the beauty of it is that any plant material, without exception—from weeds and fallen leaves to swamp cattails and the vast floating growths that clog innumerable rivers in Latin America and Africa—can be used as feedstock for the process.

As for converting trash, it doesn't matter whether the feedstock is composed of packaging materials, old rags, used candy wrappers, plastic forks, or Styrofoam coffee cups. The stuff is all just compounds of carbon, hydrogen, and oxygen, with a few impurities thrown in here and there, and all of it can be pyrolyzed and reacted with steam to produce synthesis gas, and then methanol.

The chemical equations specifying all the reactions we've discussed are shown in table 5.8. In table 5.8, a positive energy input means that energy is needed to drive the reaction, while a negative energy input means that the reaction produces energy.

The chemistry needed to dethrone oil from its trump-suit status is well understood. We can readily convert our fuel strong suits into an alcohol supply bountiful enough to wash OPEC off the map.

The only issue is that we need to have cars and trucks that can use it. This will be the subject of our next chapter.

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