Hydrogen-containing fuels

There is, of course, a chemical effect in carbon monoxide flames. This point was mentioned in the discussion of carbon monoxide explosion limits. Studies have shown that CO flame velocities increase appreciably when small amounts of hydrogen, hydrogen-containing fuels, or water are added. For 45% CO in air, the flame velocity passes through a maximum after approximately 5% by volume of water has been added. At this point, the flame velocity is 2.1 times the value with 0.7% H20 added. After the 5% maximum is attained a dilution effect begins to cause a decrease in flame speed. The effect and the maximum arise because a sufficient steady-state concentration of OH radicals must be established for the most effective explosive condition. 

A fuel cell produces electricity directly from the electrochemical reaction of hydrogen, from a hydrogen-containing fuel, and oxygen from the air. Hydrogen is industrially produced by steam reformation of naphtha oil, methane and methanol. High-purity hydrogen has been mainly used as a fuel for low-temperature fuel cells such as polymer or alkaline electrolyte fuel cells (Lin and Rei, 2000). 

Enzymes have been considered in bio fuel cells as anode electrocatalysts since their use avoids the problem of poisoning the anode with carbon monoxide present in reforming gas, allowing the use of cheap hydrogen-containing fuels such as methanol. Even though enzymatic fuel cells have been reported to have power output and stability limitations, some of them are currently being used to produce electricity to power small electrical devices with power demands in the order of micro- and milh- Watts as power output limitations are overcome. 

Hydrogen-containing fuels have a fuel value based on their mass % H. Rank the following compounds from highest mass % H to lowest ethane, propane, benzene, ethanol, cetyl palmitate (whale oil, C32H64O2). 

Table 1. Technical targets fuel cell stack sterns operating on hydrogen-containing fuel from a fuel processor (gasoline reformate) in 50 kWe (net) fuel cell sterns (Excludes fuel processing/delivery system) (Includes fuel cell ancillaries thermal, water, air management systems) All targets must be achieved simultaneously and are consistent with those of FreedomCAR ...

Whenever a hydrogen containing fuel is burned, water vapor is produced. 

A hydrogen containing fuel such as red gum or dextrin, when used as one fuel, will serve as a color enhancer as it will produce H2O when burned. 

Fuel cells are used to convert hydrogen, or hydrogen-containing fuels, directly into electrical energy plus heat through the electrochemical reaction of hydrogen and oxygen into water. The process is that of electrolysis in reverse. Overall reaction [152] ... 

Electrode for electrochemical oxidation reactions. In solid oxide fuel cells, hydrogen-containing fuels are oxidized by oxygen ions transported through an electrolyte to form water vapor or CO2 as the reaction products at this electrode. SOFC anodes may also act as fuel reforming catalysts when hydrocarbon-based fuels are supplied to the anodes. Electrode for electrochemical reduction reactions. In solid oxide fuel cells, oxygen in ambient air is reduced to oxygen ions at this electrode. 

General While Ni/YSZ cermet is the most preferred anode material for SOFCs operating with hydrogen-containing fuels, there are several efforts to find alternative materials for the SOFC anode. Many studies on oxide anodes have been made for perovskite-related oxides. LaCr03 [230-237], LaFeOs [238], LaTiOs [239], and SrTiOs [240-243] systems are considered as possible alternative anode materials. 

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