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The catalytic oxydehydrogenation of ethane to ethene
N3
surprising, occasionally even bizarre, to those of us who have professional interests in the subject (e.g. see News Brief in Appl. Catal., 84 (1992) N22). One use we can all agree with is the title of a museum of the chemical industry at Widnes in the north west of England, an area rich in the history of the chemical industry. We send our congratulations to “Catalyst” for winning first prize in the 1992 Whitbread North West Museum awards for its development of “Scientrific”, a fl m hands-on exhibition that brings the science and technology of the chemical industry to life (Chem. Brit., 28 (1992) 596). Although the more reactionary and pedantic of us no doubt object to the bastard word formed by the misalliance of “science” and “terrific” (though it could be argued that it is all right as both words come through the Latin), the director of the museum, Dr. Gordon Rintoul, reports that the number of visitors has soared since the opening of “Scientrific”.
A Fe/Al203 catalyst for Selective Hydrogenation of Dienes to Linear Internal Alkenes
A new type of Fe/Al203 catalyst has been developed for the above reaction by Z.-J. Lu et al., Dalian Institute of Chemical Physics, Academia Sinica (See Chinese J. Petrochem. Tech., 20(1991)454). It is reported that the performance of the sulphurized catalyst is marked by its excellent activity and good selectivity. The properties of the activated catalyst were investigated by temperature-programmed reduction and Mossbauer spectroscopy. The results indicate that the Fez03 phase in the as-prepared catalyst changes into a Fen-& phase (Ocxcl) during the sulphurization of the catalyst. applied catalysis A: General
The selectivity increases with increasing proportion of the Fert-x)S phase, the formation of which depends on the properties of the support used and the sulphurizing condition.
The Catalytic Oxydehydrogenation of Ethane to Ethene
Y.-G. Han and his co-workers (Research Institute of Lanzhou Chemical Industry Co.) have reported work on the conversion of ethane to ethene via catalytic oxydehydrogenation in three papers. (See Chinese J. Petrochem. Tech., 20 (1991) 229, 20 (1991) 309 and 20 (1991) 380.) The first paper concerns the development of the catalysts which were tested. These were composed of the mixed oxides of Mo-V-Nb and other transition metals. The reaction was carried out in a micro-reactor in the temperature range 300’0 400°C using a gas feed of composition CzH4:Oz:Nz = 1:1:10.2 (mol ratio). The results indicate that the activity increases as the proportion of the additional metal component increases. A catalyst composed of Mo-V-Nb-Sb-Ca was found to have excellent catalytic performance. It gave an ethane conversion of 48% and an ethene selectivity of 73% at atmospheric pressure and 400°C. It is claimed that this catalyst gave a steady conversion of ethane of 35% and a yield of ethene of 29.5% during 220 h on stream. (Conditions: sv=340 h-l, temperature = 380°C atmospheric pressure.) The second paper deals with the characterization of a series of catalysts by means of the XRD, EPR and XPS techniques. The results indicate that the active phase of the catalysts is a 6~~ type compound
(Mo1-x(VNb)x]s014
Volume 89 No. 1 -
(Ocx
25 September 1992
which
is composed
of a mixture of
[Mm.db.o7]5 014 and [Mm.d%.o915014. The catalytic activity increases with increasing content of this compound. The authors have proposed that the active centre is (Mo-O)-nV. The third paper introduces work on the kinetics of ethane oxydehydrogenation to ethene over the Mo-V-Nb-Sb-Ca catalysts at atmospheric pressure and in the temperature range of 340380°C. The results show that the overall conversion rate of ethane is zero order with respect to oxygen partial pressure, the product ethene having no inhibitive effect on the reaction, and first order with respect to ethane partial pressure. A kinetic expression is given and the reaction mechanism is discussed.
Commercial News
With the phasing-out of CFCs and, probably, HCFCs there is a race to manufacture alternative materials with equivalent properties for the various applications but also with much lower ozone depletion potential. It appears that Du Pont have beaten ICI by a short head (Chem. Brit., 28 (1992) 591). Du Pont has started up a pilot plant for the manufacture of the refrigerant HFC32 (otherwise known to the rest of us as difluoromethane) at Wilmington, Delaware, USA. Production is described as a few tons annually and a second larger plant, under construction at Deepwater, New Jersey, USA, is scheduled for start-up later this year. Du Pont has not revealed the cost of the plant. ICI has been building its own E4m pilot plant at Widnes, Cheshire, UK, for commercial test quantities of HFC32. This plant is due on stream “shortly”, according to a company spokeswoman. ICI is to close its halon1 plant by applied catalysis A: General
the end of 1993, six years before the phase-out date agreed under the Montreal Protocol (Chem. Ind., (6 July 1992) 470). If efforts to reclaim existing stocks of the fire-fighting chemical are successful, the plant could close even sooner. A new process for the catalytic co-synthesis of ethylene glycol and dimethyl carbonate through the transesterification of ethylene carbonate with methanol has been developed by Texaco Chemical Co. (J. Haggin, Chem. Eng. News, 70(18) (4 May 1992) 25). Feedstocksforthe co-synthesis are available from established commercial processes. The co-synthesis route to ethylene glycol avoids the selectivity problems of the hydration of ethylene oxide and allows dimethyl carbonate to be made in existing ethylene oxide plants. This route is very attractive if dimethyl carbonate is required in large quantities. In the oil refining area two new processes were described at the 1992 American Petroleum Refiners meeting. Haldor Topsoe A/S has developed a low-pressure (ca. 800 psig), two-stage process for combining deep HDS and hydrodearomatisation (HDA) of diesel fuels (P. Soegaard-Andersen, B.H. Cooper and P.N. Hannarup, NPRA 1992 Annual Meeting (New Orleans, 22-24 March 1992) Paper #AM-92-50). The process allows the production of diesel fuels with less than 10 wt. ppm of sulphur and less than 5 vol.-% of aromatics. The initial hydrotreatment employs one or two beds of a Topsoe high-activity Ni-MO catalyst, TK-525, and the final hydrotreatment uses a Topsoe sulphur-tolerant noble metal catalyst, TK-908. A catalytic reforming process, Octanizing, was described by staff of the lnstitut Francais du P&role (C. Mansuy, J. Andrews et al., NPRA 1992 Annual Meeting
Volume 89 No. 1 -
25 September 1992
surprising, occasionally even bizarre, to those of us who have professional interests in the subject (e.g. see News Brief in Appl. Catal., 84 (1992) N22). One use we can all agree with is the title of a museum of the chemical industry at Widnes in the north west of England, an area rich in the history of the chemical industry. We send our congratulations to “Catalyst” for winning first prize in the 1992 Whitbread North West Museum awards for its development of “Scientrific”, a fl m hands-on exhibition that brings the science and technology of the chemical industry to life (Chem. Brit., 28 (1992) 596). Although the more reactionary and pedantic of us no doubt object to the bastard word formed by the misalliance of “science” and “terrific” (though it could be argued that it is all right as both words come through the Latin), the director of the museum, Dr. Gordon Rintoul, reports that the number of visitors has soared since the opening of “Scientrific”.
A Fe/Al203 catalyst for Selective Hydrogenation of Dienes to Linear Internal Alkenes
A new type of Fe/Al203 catalyst has been developed for the above reaction by Z.-J. Lu et al., Dalian Institute of Chemical Physics, Academia Sinica (See Chinese J. Petrochem. Tech., 20(1991)454). It is reported that the performance of the sulphurized catalyst is marked by its excellent activity and good selectivity. The properties of the activated catalyst were investigated by temperature-programmed reduction and Mossbauer spectroscopy. The results indicate that the Fez03 phase in the as-prepared catalyst changes into a Fen-& phase (Ocxcl) during the sulphurization of the catalyst. applied catalysis A: General
The selectivity increases with increasing proportion of the Fert-x)S phase, the formation of which depends on the properties of the support used and the sulphurizing condition.
The Catalytic Oxydehydrogenation of Ethane to Ethene
Y.-G. Han and his co-workers (Research Institute of Lanzhou Chemical Industry Co.) have reported work on the conversion of ethane to ethene via catalytic oxydehydrogenation in three papers. (See Chinese J. Petrochem. Tech., 20 (1991) 229, 20 (1991) 309 and 20 (1991) 380.) The first paper concerns the development of the catalysts which were tested. These were composed of the mixed oxides of Mo-V-Nb and other transition metals. The reaction was carried out in a micro-reactor in the temperature range 300’0 400°C using a gas feed of composition CzH4:Oz:Nz = 1:1:10.2 (mol ratio). The results indicate that the activity increases as the proportion of the additional metal component increases. A catalyst composed of Mo-V-Nb-Sb-Ca was found to have excellent catalytic performance. It gave an ethane conversion of 48% and an ethene selectivity of 73% at atmospheric pressure and 400°C. It is claimed that this catalyst gave a steady conversion of ethane of 35% and a yield of ethene of 29.5% during 220 h on stream. (Conditions: sv=340 h-l, temperature = 380°C atmospheric pressure.) The second paper deals with the characterization of a series of catalysts by means of the XRD, EPR and XPS techniques. The results indicate that the active phase of the catalysts is a 6~~ type compound
(Mo1-x(VNb)x]s014
Volume 89 No. 1 -
(Ocx
25 September 1992
which
is composed
of a mixture of
[Mm.db.o7]5 014 and [Mm.d%.o915014. The catalytic activity increases with increasing content of this compound. The authors have proposed that the active centre is (Mo-O)-nV. The third paper introduces work on the kinetics of ethane oxydehydrogenation to ethene over the Mo-V-Nb-Sb-Ca catalysts at atmospheric pressure and in the temperature range of 340380°C. The results show that the overall conversion rate of ethane is zero order with respect to oxygen partial pressure, the product ethene having no inhibitive effect on the reaction, and first order with respect to ethane partial pressure. A kinetic expression is given and the reaction mechanism is discussed.
Commercial News
With the phasing-out of CFCs and, probably, HCFCs there is a race to manufacture alternative materials with equivalent properties for the various applications but also with much lower ozone depletion potential. It appears that Du Pont have beaten ICI by a short head (Chem. Brit., 28 (1992) 591). Du Pont has started up a pilot plant for the manufacture of the refrigerant HFC32 (otherwise known to the rest of us as difluoromethane) at Wilmington, Delaware, USA. Production is described as a few tons annually and a second larger plant, under construction at Deepwater, New Jersey, USA, is scheduled for start-up later this year. Du Pont has not revealed the cost of the plant. ICI has been building its own E4m pilot plant at Widnes, Cheshire, UK, for commercial test quantities of HFC32. This plant is due on stream “shortly”, according to a company spokeswoman. ICI is to close its halon1 plant by applied catalysis A: General
the end of 1993, six years before the phase-out date agreed under the Montreal Protocol (Chem. Ind., (6 July 1992) 470). If efforts to reclaim existing stocks of the fire-fighting chemical are successful, the plant could close even sooner. A new process for the catalytic co-synthesis of ethylene glycol and dimethyl carbonate through the transesterification of ethylene carbonate with methanol has been developed by Texaco Chemical Co. (J. Haggin, Chem. Eng. News, 70(18) (4 May 1992) 25). Feedstocksforthe co-synthesis are available from established commercial processes. The co-synthesis route to ethylene glycol avoids the selectivity problems of the hydration of ethylene oxide and allows dimethyl carbonate to be made in existing ethylene oxide plants. This route is very attractive if dimethyl carbonate is required in large quantities. In the oil refining area two new processes were described at the 1992 American Petroleum Refiners meeting. Haldor Topsoe A/S has developed a low-pressure (ca. 800 psig), two-stage process for combining deep HDS and hydrodearomatisation (HDA) of diesel fuels (P. Soegaard-Andersen, B.H. Cooper and P.N. Hannarup, NPRA 1992 Annual Meeting (New Orleans, 22-24 March 1992) Paper #AM-92-50). The process allows the production of diesel fuels with less than 10 wt. ppm of sulphur and less than 5 vol.-% of aromatics. The initial hydrotreatment employs one or two beds of a Topsoe high-activity Ni-MO catalyst, TK-525, and the final hydrotreatment uses a Topsoe sulphur-tolerant noble metal catalyst, TK-908. A catalytic reforming process, Octanizing, was described by staff of the lnstitut Francais du P&role (C. Mansuy, J. Andrews et al., NPRA 1992 Annual Meeting
Volume 89 No. 1 -
25 September 1992