Methane evolution test

Samples of HY zeolite were exhaustively treated with successive doses of tetramethylsilane in a static reactor at different temperatures in the range 250°-650°C. Rate data for methane evolution were obtained, and the kinetics were discussed. Silicon and some carbon were incorporated, giving gray materials parts of which were calcined in oxygen. Samples of the original H Y, the treated zeolite, and calcined materials were tested for their abilities to accept electrons from perylene and to isomerize cyclopropane and protoadamantane. The treated zeolite had good electron transfer properties but low and high activities for the isomerizations, respectively. However, the opposite was true for the calcined materials. These results are discussed in terms of the acidic properties of the modified zeolites. 

The evolution of carbon dioxide or methane from a substrate rqpresents a direct parameter for mineralisation. Therefore, gas evolution tests can be... 

Notwithstanding the difficulties of testing in anaerobic environments, several laboratory methods, as indicated earlier, have been developed. These measure carbon dioxide and methane evolution. The ASTM standard was developed on the basis of work from Europe (28) and is widely used for these polymers (29). Several variants on this method reported for example by Barlaz and co-workers (30) for a variety of polymers including polyesters, acrylates, cellulosics, and others are used. Similarly, the earlier pioneering work of McCarthy and co-workers is also useful (31). 

Learning of chemical concepts is assessed through two tests and homework assignments. Many of the questions on the tests require students to connect chemical concepts to issues relevant to chemical evolution or chemical processes important for life. For example, questions look at the possibility of life on Titan and the potential for successful life on Titan. This requires students to address this possibility in terms of energy sources, temperature, chemical processes given Titan s atmosphere, and the differences in chemical and physical processes in a liquid methane environment versus water. 

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