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Speciality chemicals from synthesis gas
N4
stabilizing elements in unusual valence states, in addition to unusual states of aggregation and complexation. Most catalysts which are able to catalyze the reduction of NOx suffer from the handicap that they first reduce oxygen if present in the same stack gas. For the novel copper/zeolite combinations, however, it has been found that oxygen not only does not impair the reduction of NOx by molecules such as propane; it even enhances it! A gas which contains, besides the NOx and propane, a fairly large amount of oxygen, still converts all the NOx to environmentally-neutral nitrogen W.M.H. SACHTLER
Chemical Engineering Research in the Netherlands
.An interesting account of Chemical Engineering Research in the Netherlands is provided in a recent issue of Chemical Engineering Research and Design (Institute Chem. Engrs. Pan A). The issue (Vol. 70, March 1992) is a special one devoted to “Process Design”. Work being carried out in the six departments of chemical engineering located at Delft, Eindhoven, Twente, Groningen, Amsterdam and Wageningen is described. Catalysis appears in various areas including packed bed reactors (Westerterp, Twente); gas-solid fluidized beds (Van Swaaij, Twente; Van den Bleek and Van den Akker, Delft; Thoenes, Eindhoven), bubble column reactors (Van Dierendonck, DSM, Westerterp); and threephase fluidized beds (Beenackers, Groningen; Luybod, Delft; Krishna, Amsterdam). applied catalysis A: General
Some innovative reactor configurations are being examined. As an alternative to the trickle bed reactor, a bead string reactor is being developed at Delft (Van den Bleek). Considerable effort is being made in studying membrane reactors, particularly for the selective removal of product in reactions such as the dehydrogenation of ethyl benzene to styrene; dehydrogenation of propane and hydrogen production via steam reforming (with selective hydrogen separation). Other topics impinging on catalysis include drying, particle separations, reactor stability and dynamics, particle technology and surface colloidal and interfacial phenomena.
Speciality Chemicals from Synthesis Gas
This is the title of an overview by Lin and Krifton to be found in CHEMTECH (April 1992, p. 248). The article covers ground otherthan that with which most of us working in this area are familiar, and concentrates on the use of carbon monoxide and hydrogen as building blocks for the manufacture of amidocarbonylation products. The incorporation of N is via acetamide, or HCN+NHs. The “organic” feedstock can comprise alkenes or aldehydes. Potentially attractive products include: - C14-Cl0 alkyl amidoacids (surfactants) - aspartame (intermediates for sweetness) - glutamic acid (food additives) - polyamidoacids (chelating agents) Catalysts consist of Rh-Co bimetallic complexes, cobalt in combination with certain bidentate phosphines, cobalt carbonyls and rhodium complexes. Volume 86 No. 1 -
14 July 1992
N5
Some very useful chemistry is discussed and a good deal of reference is made to several patents assigned to the Texaco Chemical Company. lsoplus Catalyst from Engelhard The Engelhard Corp. have announced the development of new refinery catalysts which could lead to dramatic increases in the yield of isobutene from refinery operations. IsoPlus catalysts are aimed at helping to satisfy projected increases in the demand for the production of MTBE which in turn requires isobutene to be available in larger quantities than present. The use of these catalysts is seen to offer a more attractive option than, for example, investment in a butane dehydrogenation plant. (Source: Chem. & Eng. News, April 20 (1992) p. 5.) Methane Activation and Methane Coupling The wealth of mechanistic information of relevance to catalysis that can be provided by the appropriate use of isotopically labelled molecules is well known. It is somewhat surprising that not much use is apparently being made of such techniques. Fortunately, some papers do appear from time to time and, in a recent article, Lapszewicz and Jiang examine the CSIRO’s OXCO catalysts for methane coupling (Catal. Lett 13 (1992) p. 103). By using CH4-D2 and ‘60z-180z experiments, information was obtained on the ability of the catalysis (SmzOs, MgO, yAl2O3) to activate both methane and oxygen. The authors find no direct correlation between the rate of methane coupling and the rate of activation of methane and applied catalysis A: General
suggest that the formulation of the methyl radical cannot be described as a simple one-step process. Some Recent Chemical Communications Chauvin and Commerene (J. Chem. Sot., Chem. Comm., (1992) 462) describe a method for the chemical counting and characterization of the active sites present on rhenium/alumina metathesis catalysts. The results support the surface carbene hypothesis and, in addition, offer some insights on the mechanism of catalyst deactivation. A novel Pt” ion/Pt’ catalyst system for the direct oxidation of ethane to acetic glycolic acids has been described by Sen and Lin (J. Chem. Sot., Chem. Comm., (1992) 508). It is proposed that initial C-H activation occurs at the Pt” centre, associated with the use of &PtCl4. Ethanol and ethylene glycol are formed and these are subsequently oxidised by the corresponding carboxylic acids by the metallic Pt, associated with the use of Pt black. The reactions take place in aqueous media and under mild conditions. Combined Catalytic Removal of SWNO, from Flue Gases Haldor Topsoe A& Lyngby, Denmark, has commercialized a catalytic process for the removal of SOx and NOx from flue gases. The process, called SNOX Process, is capable of removing more than 95% of SOx and NOx. While NOx is reduced by ammonia by the usual SCR reactions, SOx is converted to 94-97% sulphuric acid that can be used for fertilizer production and other industrial purposes. The proVolume 86 No. 1 -
14 July 1992
stabilizing elements in unusual valence states, in addition to unusual states of aggregation and complexation. Most catalysts which are able to catalyze the reduction of NOx suffer from the handicap that they first reduce oxygen if present in the same stack gas. For the novel copper/zeolite combinations, however, it has been found that oxygen not only does not impair the reduction of NOx by molecules such as propane; it even enhances it! A gas which contains, besides the NOx and propane, a fairly large amount of oxygen, still converts all the NOx to environmentally-neutral nitrogen W.M.H. SACHTLER
Chemical Engineering Research in the Netherlands
.An interesting account of Chemical Engineering Research in the Netherlands is provided in a recent issue of Chemical Engineering Research and Design (Institute Chem. Engrs. Pan A). The issue (Vol. 70, March 1992) is a special one devoted to “Process Design”. Work being carried out in the six departments of chemical engineering located at Delft, Eindhoven, Twente, Groningen, Amsterdam and Wageningen is described. Catalysis appears in various areas including packed bed reactors (Westerterp, Twente); gas-solid fluidized beds (Van Swaaij, Twente; Van den Bleek and Van den Akker, Delft; Thoenes, Eindhoven), bubble column reactors (Van Dierendonck, DSM, Westerterp); and threephase fluidized beds (Beenackers, Groningen; Luybod, Delft; Krishna, Amsterdam). applied catalysis A: General
Some innovative reactor configurations are being examined. As an alternative to the trickle bed reactor, a bead string reactor is being developed at Delft (Van den Bleek). Considerable effort is being made in studying membrane reactors, particularly for the selective removal of product in reactions such as the dehydrogenation of ethyl benzene to styrene; dehydrogenation of propane and hydrogen production via steam reforming (with selective hydrogen separation). Other topics impinging on catalysis include drying, particle separations, reactor stability and dynamics, particle technology and surface colloidal and interfacial phenomena.
Speciality Chemicals from Synthesis Gas
This is the title of an overview by Lin and Krifton to be found in CHEMTECH (April 1992, p. 248). The article covers ground otherthan that with which most of us working in this area are familiar, and concentrates on the use of carbon monoxide and hydrogen as building blocks for the manufacture of amidocarbonylation products. The incorporation of N is via acetamide, or HCN+NHs. The “organic” feedstock can comprise alkenes or aldehydes. Potentially attractive products include: - C14-Cl0 alkyl amidoacids (surfactants) - aspartame (intermediates for sweetness) - glutamic acid (food additives) - polyamidoacids (chelating agents) Catalysts consist of Rh-Co bimetallic complexes, cobalt in combination with certain bidentate phosphines, cobalt carbonyls and rhodium complexes. Volume 86 No. 1 -
14 July 1992
N5
Some very useful chemistry is discussed and a good deal of reference is made to several patents assigned to the Texaco Chemical Company. lsoplus Catalyst from Engelhard The Engelhard Corp. have announced the development of new refinery catalysts which could lead to dramatic increases in the yield of isobutene from refinery operations. IsoPlus catalysts are aimed at helping to satisfy projected increases in the demand for the production of MTBE which in turn requires isobutene to be available in larger quantities than present. The use of these catalysts is seen to offer a more attractive option than, for example, investment in a butane dehydrogenation plant. (Source: Chem. & Eng. News, April 20 (1992) p. 5.) Methane Activation and Methane Coupling The wealth of mechanistic information of relevance to catalysis that can be provided by the appropriate use of isotopically labelled molecules is well known. It is somewhat surprising that not much use is apparently being made of such techniques. Fortunately, some papers do appear from time to time and, in a recent article, Lapszewicz and Jiang examine the CSIRO’s OXCO catalysts for methane coupling (Catal. Lett 13 (1992) p. 103). By using CH4-D2 and ‘60z-180z experiments, information was obtained on the ability of the catalysis (SmzOs, MgO, yAl2O3) to activate both methane and oxygen. The authors find no direct correlation between the rate of methane coupling and the rate of activation of methane and applied catalysis A: General
suggest that the formulation of the methyl radical cannot be described as a simple one-step process. Some Recent Chemical Communications Chauvin and Commerene (J. Chem. Sot., Chem. Comm., (1992) 462) describe a method for the chemical counting and characterization of the active sites present on rhenium/alumina metathesis catalysts. The results support the surface carbene hypothesis and, in addition, offer some insights on the mechanism of catalyst deactivation. A novel Pt” ion/Pt’ catalyst system for the direct oxidation of ethane to acetic glycolic acids has been described by Sen and Lin (J. Chem. Sot., Chem. Comm., (1992) 508). It is proposed that initial C-H activation occurs at the Pt” centre, associated with the use of &PtCl4. Ethanol and ethylene glycol are formed and these are subsequently oxidised by the corresponding carboxylic acids by the metallic Pt, associated with the use of Pt black. The reactions take place in aqueous media and under mild conditions. Combined Catalytic Removal of SWNO, from Flue Gases Haldor Topsoe A& Lyngby, Denmark, has commercialized a catalytic process for the removal of SOx and NOx from flue gases. The process, called SNOX Process, is capable of removing more than 95% of SOx and NOx. While NOx is reduced by ammonia by the usual SCR reactions, SOx is converted to 94-97% sulphuric acid that can be used for fertilizer production and other industrial purposes. The proVolume 86 No. 1 -
14 July 1992