Coking characteristics

At high metals levels, the coking characteristics of a cracking catalyst can be greatly increased that is, the ratio of contaminant coke to catalytic coke can be quite high. The effect of the contaminant metals on the coke response is affected not only by the level of metals but also by the type of catalyst and the use of a metals passivator. Catalysts, which contain effective metals traps to inhibit the contaminant effects, do produce much less contaminant coke than catalyst without metal traps. 

Properties Involving Utilization. Coal rank is the most important single property for appHcation of coal. Rank sets limits on many properties such as volatile matter, calorific value, and swelling and coking characteristics. Other properties of significance include grindabHity, ash content and composition, and sulfur content. 

Bogdanort, J. M., and Rase, H. F., Characteristics of a Commercially Aged Ni-Mo/AL203 Hydrotreating Catalyst Component Distribution, Coke Characteristics, and Effects of Regeneration. Ind. Eng. Chem. Prod. Res. Dev, 1986. 25 pp. 220-230. 

Based on the fact that the pore formation increases at higher rates of heating, an attempt was made to produce a porous coke by applying high rates of heating to a coal that showed no coking characteristics at normal heating rates. A lean coal with 10.6% volatile matter daf was used, and the... 

The material thought to be responsible for conferring the plastic properties on coal can be removed by solvent extraction to leave a nonplastic residue (Pierron and Rees, 1960). Plastic properties can be restored to the coal be recombining the solvents extracts with the insoluble residue. The fluid behavior or plasticity of coal in the temperature range 300 to 550°C (572 to 1022°F) is widely used to estimate coking characteristics and may be important for predicting coal properties with respect to coal conversion processes. 

Cracking of heavy petroleum residue Al-S Saponite showed higher activity than y alumina with similar gasoline selectivity and coking characteristic to a steamed FCC. 5o... 

Determination of Oxidation Kinetics. The reaction rate between oxygen and coke depends upon the oxygen partial pressure, the composition, morphology and location of coke, and the catalytic effect of catalyst components and impurities. Therefore, the study of the kinetics of coke oxidation provides information regarding coke characteristics. Additionally, it is necessary to... 

Tests for coke characteristics can be divided into two major classes chemical and physical. Considering chemical tests first, there are ultimate analysis and proximate analysis for the coke. Another chemical property, reactivity, which refers to the ability of coke to react with carbon dioxide, has also been proposed (Schapiro and Gray, 1963 Miller et al., 1965 Rao and Jalon, 1972 Daly and Budge, 1974) the ASTM does not provide a standard reactivity test procedure. 

Standard procedure Coke characteristics iSO 556 iSO 556 ISO 1881 ASTM D294 JIS K2151... 

Rahimi, P. Gentzis, T. Ciofani, T. Coking characteristics of partially deasphalted oils, Proc. AIChE Spring Nat. Mtg., Session 71 - Advances in Coking, Atlanta, GA, 428,2000. 

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