Ignition temperature carbon monoxide

In the early days of catalytic cracking, the catalysts were highly temperature sensitive requiring regenerator temperatures to be limited to 1100°F. Temperatures in excess of 1150°F would ignite the carbon monoxide resulting in... 

Fig. 3. Pressure required for ignition of mixtures of acetylene and a diluent gas (air, oxygen, butane, propane, methane, carbon monoxide, ethylene, oil gas, nitrogen, helium, or hydrogen) at room temperature. Initiation fused resistance wire. Container A, 50 mm dia x 305 mm length (73) B,...

Direct-Flame Incinerators. In direct-flame incineration, the waste gases are heated in a fuel-fired refractory-lined chamber to the autoignition temperature where oxidation occurs with or without a visible flame. A fuel flame aids mixing and ignition. Excess oxygen is required, because incomplete oxidation produces aldehydes, organic acids, carbon monoxide, carbon soot, and other undesirable materials. 

Oxidation. Carbon monoxide can be oxidized without a catalyst or at a controlled rate with a catalyst (eq. 4) (26). Carbon monoxide oxidation proceeds explosively if the gases are mixed stoichiometticaHy and then ignited. Surface burning will continue at temperatures above 1173 K, but the reaction is slow below 923 K without a catalyst. HopcaUte, a mixture of manganese and copper oxides, catalyzes carbon monoxide oxidation at room temperature it was used in gas masks during World War I to destroy low levels of carbon monoxide. Catalysts prepared from platinum and palladium are particularly effective for carbon monoxide oxidation at 323 K and at space velocities of 50 to 10, 000 h . Such catalysts are used in catalytic converters on automobiles (27) (see Exhaust CONTHOL, automotive). 

Occurrence. Carbon monoxide is a product of incomplete combustion and is not likely to result where a flame bums in an abundant air supply, yet may result when a flame touches a cooler surface than the ignition temperature of the gas. Gas or coal heaters in the home and gas space heaters in industry have been frequent sources of carbon monoxide poisoning when not provided with effective vents. Gas heaters, though properly adjusted when installed, may become hazardous sources of carbon monoxide if maintained improperly. Automobile exhaust gas is perhaps the most familiar source of carbon monoxide exposure. The manufacture and use of synthesis gas, calcium carbide manufacture, distillation of coal or wood, combustion operations, heat treatment of metals, fire fighting, mining, and cigarette smoking represent additional sources of carbon monoxide exposure (105—107). 

Beyond the catalytic ignition point there is a rapid increase in catalytic performance with small increases in temperature. A measure of catalyst performance has been the temperature at which 50% conversion of reactant is achieved. For carbon monoxide this is often referred to as CO. The catalyst light-off property is important for exhaust emission control because the catalyst light-off must occur rehably every time the engine is started, even after extreme in-use engine operating conditions. 

Emission factors must be also critically examined to determine the tests from which they were obtained. For example, carbon monoxide from an automobile will vary with the load, engine speed, displacement, ambient temperature, coolant temperature, ignition timing, carburetor adjustment, engine condition, etc. However, in order to evaluate the overall emission of carbon monoxide to an area, we must settle on an average value that we can multiply by the number of cars, or kilometers driven per year, to determine the total carbon monoxide released to the area. 

Fire Hazards - Flash Point Not flammable Flammable Limits in Air (%) Not flammable Fire Extinguishing Agents Not pertinent Fire Extinguishing Agents Not To Be Used Not pertinent Special Hazards of Combustion Products Toxic carbon monoxide gas may form in fire Behavior in Fire Not pertinent Ignition Temperature Not pertinent Electrical Hazard Not pertinent Burning Rate Not pertinent. 

Above 150-200°C, incandescence occurs with fluorine, chlorine or iodine. In presence of moisture, contact at ambient temperature with carbon monoxide or carbon dioxide causes ignition, while dry sulfur dioxide causes incandescence on heating. 

Mixtures of potassium and solid carbon dioxide are shock-sensitive and explode violently on impact, and carbon monoxide readily reacts to form explosive carbonylpotassium (potassium benzenehexoxide) [1]. Dichlorine oxide explodes on contact with potassium [2], Potassium ignites in dinitrogen tetraoxide or dinitrogen pentaoxide at ambient temperature and incandesces when warmed with nitrogen oxide or phosphorus(V) oxide [3], At — 50°C, potassium and carbon monoxide react to give dicarbonylpotassium, which explodes in contact with air or water, or at 100°C. At 150°C, the product is a trimer of this, potassium benzenehexoxide. The just-molten metal ignites in sulfur dioxide [4],... 

Carbon monoxide is a stable gas. Metal carbonyls are relatively unstable and sensitive to light and moderately high temperatures. They may spontaneously ignite on contact with air. Volatile agents are stored in steel cylinders otherwise, agents are stored in steel or glass containers. Metal carbonyls may be stored under an inert gas blanket, such as nitrogen, to prevent contact with the air. 

Prettre [41] found that potassium chloride sprayed in a mixture of carbon monoxide and air considerably raises the ignition temperature of these mixtures (Table... 

---