Promoted combustion-test

R. Zawierucha,). F. Million Promoted Ignition-Combustion Tests of Brazed Alimiinum Heat Exchanger Samples in Gaseous and Liquid Oxygen Environments, in Flammability and Sensitivity of Materials in Oxygen-Enriched Atmospheres Vol. 9, ASTM STP 1395,... 

The combustibility tests demonstrate that introducing PEDA into the compositions based on PVC resin promotes formation of a large coke layer the coating film does not bum, because the presence of nitrogen in the modifying additive enables an enhancement of the fire and heat resisting effect. 

As example, the spent FCC catalysts were tested and compared for different combustion tests. The catalysts were promoted with 300 and 800 ppm Pt and Ce on alumina (220 m /g) and mixed oxides (1-5). Platinum was impregnated with hexachloroplatinic acid (H2PtCl6) and calcined at 500 °C. Then, it was treated... 

Pressure Development Overpressure in a UVCE results from turbulence that promotes a sudden release of energy. Tests in the open without obstacles or confining structures do not produce damaging overpressure. Nevertheless, combustion in a vapor cloud within a partially confined space or around turbulence-producing obstacles may generate damaging overpressure. Also, turbulence in a jet release, such as may occur with compressed natural gas discharged from a ruptured pipehne, may result in blast pressure. 

Oxygen is toxic and deadly to breathe when in a pure state at elevated pressures. In addition, such pure oxygen promotes rapid combustion and can produce devastating fires, such as the fire that killed the Apollo 1 crew on a test launch pad in 1967. It spread rapidly because the pure oxygen was at normal pressure rather than the one-third pressure used during flight. 

Our SOx test work was done with samples which were fully promoted with Davison CP-3 Combustion Promoter (7.4 pounds per ton of cracking catalyst, 0.37%). The only exception is the data in Table II which shows the effect of not using combustion promoter. 

Effect of Additives. One of the first attempts to solve the preignition problem by additives was the use of tributyl phosphite, claimed in a patent by Campbell (14) This compound inhibited the catalytic activity of lead compounds in promoting the glowing of carbon. A later patent issued to Withrow claimed that trimethyl phosphate and trimethyl phosphite also are effective as fuel additives in inhibiting surface ignition due to leaded deposits (94). Street, in 1952, ran tests with tricresyl phosphate as an additive in leaded fuel and reported that the phosphorus compound affected the occurrence of lead compounds in the end-gas region of the combustion chamber (80). 

There has been a great recent market demand for halogen-free fire-retardant polymers. Zinc borates are also multifunctional fire retardants in halogen-free polymers. They can promote char formation, reduce the Rate of Heat Release, smoke evolution, carbon monoxide generation, and afterglow combustion. When used in conjunction with metal hydroxides, they can also display synergy in fire test performance. 

The upper half-sphere is fixed, the lower half-sphere is movable, using a pneumatic jack, to allow quick opening of the vessel for frequent cleaning. Combustion in chlorine produces soot deposits on the walls, which may promote or prevent ignition of subsequent mixtures. Cleaning after each positive test is necessary to obtain reliable flammable limits in chlorine. 

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