Fuels hydrogen gas

Fuel Gas Piping. The following are specific provisions applicable to compressor station fuel hydrogen gas piping only ... 

Hydrogen has been suggested as a convenient, clean-burning fuel. Hydrogen gas may be stored as a compressed gas or as a liquid, and it also has properties that make it suitable as a fuel for internal combustion engines in automobiles. 

Fuel, hydrogen gas (red), comes in contact with a catalytically active electrode (the anode), on the surface of which the hydrogen molecule splits into protons and electrons in the hydrogen-oxygen reaction (HOR) according to... 

In nuclear science, liquid hydrogen is used in bubble chamber detectors for high-energy particles and in the space program as a rocket fuel. Hydrogen gas is potentially a large-scale fuel in future for internal combustion engines and fuel cells. 

Removal of toxic carbon monoxide molecules is a typical depollution reaction, of interest in catalytic exhausts. Furthermore, the reaction with water is of industrial importance in producing clean fuels (hydrogen gas) in a sustainable process., whereas that with hydrogen, via hydride attack and addition of the //+ counter-ion produces formaldehyde. Formaldehyde, i.e., H2CO is a valuable molecule for organic synthesis and solvation. 

Gasification. Gasification converts soHd fuel, tars, and oils to gaseous products such as CO, H2, and CH that can be burned direcdy or used in synthesis gas (syngas) mixtures, ie, CO and mixtures for production of Hquid fuels and other chemicals (47,48) (see Coal conversion processes, gasification Euels, synthetic-gaseous fuel Hydrogen). 

Under the National Energy PoHcy Act of 1992 nonpetroleum-based transportation fuels are to be introduced in the United States. Such fuels include natural gas (see Gas, natural), Hquefied petroleum gas (qv) (LPG), methanol (qv), ethanol (qv), and hydrogen (qv), although hydrogen fuels are not expected to be a factor until after the year 2000 (see also Alcohol fuels Hydrogen energy). 

HYDROCARBONS Organic compounds that contain only hydrogen and carbon. The major sources of hydrocarbons in the atmosphere are vehicle emissions (unburned fuel) and gas leaks. Contributes to acid rain. 

Table 2 shows some safety-related physical properties of hydrogen as compared to two commonly accepted fuels, natural gas and gasoline. 

Stoichiometry has important practical applications, such as predicting how much product can be formed in a reaction. For example, in the space shuttle fuel cell, oxygen reacts with hydrogen to produce water, which is used for life support (Fig. L.l). Let s look at the calculation space shuttle engineers would have to do to find out how much water is formed when 0.25 mol 02 reacts with hydrogen gas. 

In a simple version of a fuel cell, a fuel such as hydrogen gas is passed over a platinum electrode, oxygen is passed over the other, similar electrode, and the electrolyte is aqueous potassium hydroxide. A porous membrane separates the two electrode compartments. Many varieties of fuel cells are possible, and in some the electrolyte is a solid polymer membrane or a ceramic (see Section 14.22). Three of the most promising fuel cells are the alkali fuel cell, the phosphoric acid fuel cell, and the methanol fuel cell. 

As world deposits of petroleum and coal are exhausted, new sources of hydrogen will have to be developed for use as a fuel and in the production of ammonia for fertilizer. At present, most hydrogen gas is produced from hydrocarbons, but hydrogen gas can also be generated by the electrolysis of water. Figure 19-23 shows an electrolytic cell set up to decompose water. Two platinum electrodes are dipped in a dilute solution of sulfuric acid. The cell requires just one compartment because hydrogen and oxygen escape from the cell much more rapidly than they react with each other. 

Fuel cells are electrochemical devices transforming the heat of combustion of a fuel (hydrogen, natural gas, methanol, ethanol, hydrocarbons, etc.) directly into electricity. The fuel is electrochemically oxidized at the anode, whereas the oxidant (oxygen from the air) is reduced at the cathode. This process does not follow Carnot s theorem, so that higher energy efficiencies are expected up to 40-50% in electrical energy and 80-85% in total energy (heat production in addition to electricity). 

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