ethane pyrolysis

ethane pyrolysis

N17 ological Sciences Section, both between 1976 and 1980. He served on the ‘HAS Presidium ad-hoc Committee for Eiaborating a New Concept of Research...

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N17

ological Sciences Section, both between 1976 and 1980. He served on the ‘HAS Presidium ad-hoc Committee for Eiaborating a New Concept of Research Planning and Accou~ing’ (1977-1978), on the Advisory Board of the Institute of International Relations (19781980), on the “Enzyme Nomenclature’ working committee of the IUPAC-IUB Commission on Biochemical Nomenclature until 1986, He was on the Enzyme Engineering Conference Advisory Board in 1977. He led one of the professional plenary groups on “Mechanism of Control of Vial Processes” from 1982 to 1985. He was a member of the Editorial Board of the European Journal of Biochemistry until 1980, and of that of the Acta Biochim. Biophys. Hung, until 1985. Since 1978, he was also on the Editorial Board of Oxidation Communications, He was a member of the HAS Reaction Kinetics and Catalysis Work Committee from 1974, leader of the Kinetics Club from 1973 and presided over the IUB Hungarian National Committee from 1981. He served on ICSU Hungarian National Comm~ee since 1981 and on the National Pedagogical Institute General Training Management Biological Curricular Committee since 1982. He was on the presidential committee of the computer~Aided Drug Design Society from 1981 and presided over the IUB Interest Group on Kinetics and Mechanism of Enzymes and Metabolic Networks Subgroup from 1984. He sat on the Biotechnology Work Committee since 1985. He was deputy director of the Institute of EnzytTtOlOQy until the end of 1985 and then director until his unexpected death on October 4, 1989, LASLO GUCZI

applied catalysis -

ACS Award to Bob Grasselli

tt has been announced (Chemical and Engineering News, Sept. 25th, p.75) that the ACS Award in Petroleum ~herni~~, sponsored by the Amoco Foundation, has been awarded to Robert K. Grasselli. Bob, now with Mobil Research and Development Corp., played a major role in the discovery, development and ~o~inued advancement of the Sohio one-step acrylonitrile process starting from propene, ammonia and air. This process is licensed world-wide and produces some 8 million lb of a~~lonitrile per year. Further details of Bob’s career and interests are given in the article cited above and have abo been outlined previously in these columns, Combined Pyrolysis

Methane

Coupli~g/Ethane

I have been sent a preprint of a paper to appear in Chemistry Letters (Dec. 1989) which will be of interest to those of our readers who are working on methane activation. This is a contribution by H. Mimoun, A. Robine, S. Bonnaudet and C.J. Cameron which describes a method of considerably improving the yield of ethylene in a methane coupling system by adding an ethane pyrolysis step after the coupling reactor. The paper shows that when mixtures of methane, ethane and oxygen are fed to a catalyst consisting of a mechanical mixture of SrCO, and La@&C& (catalyst peak temperature S!X.X), the oxygen is preferentially used for the oxidative dehydrogenation of ethane, However, if the ethane is added to the post-oxidation zone of the reactor (i.e. when the oxygen has been fully consumed) and the temperature of this zone is su~icient~ high (ca. 800%), the methane consumption remains high

Volume 56 No. 2 --15 December 1989

N18

and the heat of the exothermic reaction Can be used for the endothermic pyrolysis of ethanetoform ethene plus hydrogen. In the experiment reported, almost 80% of the added ethane was converted, with a selectivity of more than 85%, to ethene and propene. It is suggested that if the hydrogen formed could be used to hydrogenate selectively some of the CO and CO* formed, the overall selectivity of the”oxypyrolysis reaction” could exceed 90%. JULIAN ROSS Afternatfve Fuels to Petroleum With the search for alternatives to petroleum gaining more and more attention, a timely discussion on this subject by Joseph Haggin has appeared in Chemical and Engineering News (Aug, 1989 issue, p-25). According to this report, which quotes extensively from an interview with G. Alex Mills, oxygenates, either by themselves or as additives to fuels, appear to be the principal candidates as alternative fuels beyond the petroleum industry. This will probably also lead to a re-emergence of Cl chemistry in the times to come. The report suggests that methanol may become a serious contender as motor fuel and that a number of other higher alcohols and ethers witl also enterthe scene. These o~genates can be produced with high-octane properties from sources other than hydrocarbons and may have some environmental advantages. The benefits of reduced CO and NO, emissions with alcohol fuels are well established. On the problem of changeover from petroleum, methanol appears to be the alternatfve fuel which will be most difficult to accommodate; higher alcohols and ethers would be easier. Alcohol fuels would require higher engine compression ratios;

applied catalysis -

fu~hermore, fuel tanks would need to be larger to accommodate their lower energy densities. Of all the oxygenates, MTBE is inherently the most attractive because of its easy miscibility with petrbleum, its low vapour pressure and its high octane value. Nevertheless, if and when oxygenates achieve prominence, methanol will probably be the biggest contributor, despite the difficulties in accommodating it, Methanol production is a catalytic process and current research to develop catalysts for corlversion of methane to either methanol or ethene (which could be subsequently hydrated to methanol) is therefore of great significance. The higher alcohols have also potential as motor fuels but their successful production is handicapped by problems in catalyst development. Most of catalyst development is focused on copper-based catalysts promoted with one or more of Rb, Cs, or K. lsobutyi alcohol is of pa~j~uler interest because of its high octane rating and this can be made from syn-gas with alkali promoted zinc oxide catalysts. A classic example of a process for fuel production is Mobil’s MTG (Methanol to Gasoline) process. There have also been efforts to integrate syn-gas~methanolfhy~ drocarbon production but this requires development of a multifunctional catatyst which would allow a single reactor to be used. Integration of the Fischer-Tropsch and MTG processes is another possibility, though how such a process could work in a non-SASOL situation is debatable. K. SESHAN Odour Removal by molecular Sieves The introduction of auto-exhaust gas catalysts has led to a number of new problems, For example, as reported in a previous issue of News Brief in the past, the

Volume 56 No. 2 --I 5 December 1989