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Butene isomerization with SAPO
N20
4-(1-naphthylmethyl) bibenzyl could be cleaved under conditions relevant to coal liquefaction. The activity of carbon black is attributed to surface properties related to the presence of oxygen or nitrogen and/or the nature of the carbon structure given by the conditions of its preparation. Used tires contain about 30 wt.-% of carbon black. It was shown that this carbon black is also catalytically active for coal liquefaction. Thus, the liquefaction of a mixture of rubber tires and Illinois No. 6 coal at 425°C and 2000 psi of hydrogen yielded a liquid product of a better quality than that from thermal liquefaction of coal in tetralin.
lengths from naturally derived and readily available fatty acids such as lauric, myristic, palmitic and stearic acids. Ethylene oligomers of course give rise to an even number of carbon atoms. Interestingly, there have recently been several announcements from SASOL, pointing out that odd (and of course even) numbered linear a-alkenes are also obtained from Fischer-Tropsch conversion of synthesis gas over iron-based catalysts. It seems likely that the application of these odd numbered alkenes as, for example, co-monomers in alkene polymerization will attract increasing attention in the future. M.S. SCURRELL
ED FURIMSKY New Method for the Synthesis of Linear a-Alkenes
Supplies of linear a-alkenes are dependent on processing ethylene by means of oligomerization technology. A group of researchers at Henkel Research Corporation (Miller, Nelson and Byrne, J. Org. Chem., 58 (1993) 18) have now reported an unusually efficient and selective synthesis of 1-alkenes via decarbonylation/dehydration of the corresponding carboxylic acid containing one or more carbon atoms per molecule than the olefinic product. Reactions are conducted In the presence of acetic anhydride which is stoichiometrically converted to acetic acid; the catalysts used are based on either palladium or rhodium. The workers point out that their method opens up the way to synthesise linear a-alkene products having an odd number of carbon chain
applied catalysis A: General
Butene Isomerization with SAPO
In a recent U.S. Patent [5,132,484] issued to UOP, G.J. Gajda describes the use of non-zeolitic molecular sieves for the isomerization of butenes. The specifications are very broad and include many types of non-zeolitic molecular sieves. Specific examples describe the use of SAPO-11 for the isomerization of 2-butene at 318°C (13.2 mass-% isobutene, 13.2% 1-butene, 53.8% unreacted 2-butenes, 16% C5 and heavier) and at 343°C (26.% isobutene, 11.8% 1-butene, 38.1% 2butenes, and 1.2°/0 C5 and heavier). In contrast, a zeolitic molecular sieve catalyst gave only 1.2% isobutene, 1.2°/0 1-FAPO11, good selectivity to 1-butene above 200°C was observed, with above-equilibrium concentration values. J.N. ARMOR
Volume 96 No. 2 - - 26 March 1993
4-(1-naphthylmethyl) bibenzyl could be cleaved under conditions relevant to coal liquefaction. The activity of carbon black is attributed to surface properties related to the presence of oxygen or nitrogen and/or the nature of the carbon structure given by the conditions of its preparation. Used tires contain about 30 wt.-% of carbon black. It was shown that this carbon black is also catalytically active for coal liquefaction. Thus, the liquefaction of a mixture of rubber tires and Illinois No. 6 coal at 425°C and 2000 psi of hydrogen yielded a liquid product of a better quality than that from thermal liquefaction of coal in tetralin.
lengths from naturally derived and readily available fatty acids such as lauric, myristic, palmitic and stearic acids. Ethylene oligomers of course give rise to an even number of carbon atoms. Interestingly, there have recently been several announcements from SASOL, pointing out that odd (and of course even) numbered linear a-alkenes are also obtained from Fischer-Tropsch conversion of synthesis gas over iron-based catalysts. It seems likely that the application of these odd numbered alkenes as, for example, co-monomers in alkene polymerization will attract increasing attention in the future. M.S. SCURRELL
ED FURIMSKY New Method for the Synthesis of Linear a-Alkenes
Supplies of linear a-alkenes are dependent on processing ethylene by means of oligomerization technology. A group of researchers at Henkel Research Corporation (Miller, Nelson and Byrne, J. Org. Chem., 58 (1993) 18) have now reported an unusually efficient and selective synthesis of 1-alkenes via decarbonylation/dehydration of the corresponding carboxylic acid containing one or more carbon atoms per molecule than the olefinic product. Reactions are conducted In the presence of acetic anhydride which is stoichiometrically converted to acetic acid; the catalysts used are based on either palladium or rhodium. The workers point out that their method opens up the way to synthesise linear a-alkene products having an odd number of carbon chain
applied catalysis A: General
Butene Isomerization with SAPO
In a recent U.S. Patent [5,132,484] issued to UOP, G.J. Gajda describes the use of non-zeolitic molecular sieves for the isomerization of butenes. The specifications are very broad and include many types of non-zeolitic molecular sieves. Specific examples describe the use of SAPO-11 for the isomerization of 2-butene at 318°C (13.2 mass-% isobutene, 13.2% 1-butene, 53.8% unreacted 2-butenes, 16% C5 and heavier) and at 343°C (26.% isobutene, 11.8% 1-butene, 38.1% 2butenes, and 1.2°/0 C5 and heavier). In contrast, a zeolitic molecular sieve catalyst gave only 1.2% isobutene, 1.2°/0 1-FAPO11, good selectivity to 1-butene above 200°C was observed, with above-equilibrium concentration values. J.N. ARMOR
Volume 96 No. 2 - - 26 March 1993