Copper catalysts, for methanol synthesis

L. Ma, D.L. Trimm and M.S. Wainwright Promoted skeletal copper catalysts for methanol synthesis, in Advances of Alcohols Fuels in the World, - Proceedings of the XII International Symposium on Alcohol Fuels, Beijing, China, Tsinghua University Press, 1998, pp. 1-7. 

L. Ma and M.S. Wainwright, Development of skeletal copper-chromia catalysts I. Structure and activity promotion of chromia on skeletal copper catalysts for methanol synthesis. Appl. Catal. A General, 187 89-98, 1999. 

Tests with catalysts containing copper were carried out by Imperial Chemical Industries Ltd., England, from about 1958 to 1962 and eventually a practical copper catalyst for methanol synthesis and the first Low-pressure Methanol Processes were brought onto the market. In the process developed by ICI the quench reactor, in which the reaction heat is removed by quenching with cold gases and which is known from high-pressure methanol synthesis, is used. 

Sheffer, G.R. and King, T.S. (1989a) Potassium s promotional effect of unsupported copper catalysts for methanol synthesis. J. Catal, 115,376-387. 

Fig. 7.20 H2-TPR profiles of copper catalyst for methanol synthesis A un-reduced catalyst B reduced catedyst C edter 556 h reaction catalyst...

Fujitani, T., Saito, M., Kanai, Y, Kakumoto, T., Watanabe, T., Nakamura, J., and Uchijima, T. The role of metal oxides in promoting a copper catalyst for methanol synthesis. Catal Lett. 1994, 25, H -TI6. 

Kasatkin I, Kurr P, Kniep B, Trunschke A, Schlogl R. Role of lattice strain and defects in copper particles on the activity of Cu/ZnO/Al2C>3 catalysts for methanol synthesis. Angewandte Chemie, International Edition. 2007 46(38) 7324-7327. 

Saito M, et al. Development of copper/zinc oxide-based multicomponent catalysts for methanol synthesis from carbon dioxide and hydrogen. Appl Catal A Gen. 1996 138(2) 311—18. 

This set of experiments establishes that pure copper metal, free of surface impurities, yields less than 10 8 kg of methanol per square meter of the catalyst per hour under the standard conditions outlined above. Such a yield is far below the specific activity of supported" copper-based catalysts, e.g., 3.63 x 10 5 kg CH3OH m 2 hr-1 for the Cu/ZnO = 30/70 catalyst (39), and shows that copper metal is a very poor catalyst for methanol synthesis at 75 atm at 250°C. 

Copper and zinc containing mesoporous molecular sieves AIMCM-41 have been studied by MAS NMR, electron spin resonance, nitrogen and carbon monoxide adsorption and temperature programmed reduction. AlMCM-41 materials with ns,/nAi = 15, 30 and x have been synthesized in the presence of copper and zinc Carbon monoxide adsorption shows the presence of Cu ions after mild activation, but Zn ions have not been detected indicating that only a ZnO phase is formed Temperature programmed reduction reveals the presence of CuO clusters of various size depending on the on the ns./n ij ratio and the zinc concentration The results of this study allow the preparation of mesoporous molecular sieves with remarkable redox properties, which are potential model catalyst for methanol synthesis... 

Development of high performance Raney copper-based catalysts for methanol synthesis from CO2 and H2... 

In previous studies the authors have reported that metals oxides such as GaaOa, AI2O3, Zr02 and Cr203 contained in Cu/ZnO-based catalysts have an important role to improve simultaneously the activity and the selectivity[1, 2]. Unlike Cu/ZnO-based catalysts, Raney copper catalysts have not been widely reported in the literature as practical catalysts for methanol synthesis. However, 20 years ago Wainwright and co-workers have been the first to report the potentiel use of Raney Cu and Raney Cu-Zn as catalysts to produce methanol from syngas to use as synthetic liquid fuel [3]. Recent works of Wainwright et al. on methanol synthesis... 

Chinchen et al. have reported that, as shown in Figure 10, the activity of a variety of copper-based catalysts for methanol synthesis is proportional to the specific copper surface area irrespective of the coexisting metal oxide (support). In other words, the methanol synthesis activities per unit copper surface area are identical. It is considered from the figure that there are two possible ways of improving the activity for methanol synthesis catalysts. These are... 

The final category of chemical synthesis catalysts is the iron-based catalysts for ammonia and the copper- or chromium-based catalysts for methanol synthesis. The cost is relatively low but frie tonnage for ammonia alone is about one-fifth of total catalysts for chemicals. 

A series of binary (Cu/ZnO and C11/AI2O3) and ternary (Cu/ZnO/A Oa) copper catalysts employed in methanol synthesis has been investigated by d Alnoncourt et al. [142]. The results obtained using CO adsorption microcalorimetry showed that Cu/ZnO/AlaOa had the lowest initial heat of adsorption of 68 kJ mof and was the most active catalyst for methanol synthesis. Cu/ZnO showed a heat of adsorption of 71 kJ mol" and a lower activity, and CU/AI2O3 had the highest initial heat of adsorption of 81 kJ mof and the lowest activity. The decrease of about 10 kJ mol in the heat of adsorption of CO induced by the presence of ZnO has been attributed to strong metal-support interactions. 

Jia, L., Gao, J Fang, W and Li, Q. (2012) Influence of copper content on structural features and performance of pre-reduced LaMni 4,Cue03 (0-o l) catalysts for methanol synthesis from CO2/H2. /. Rare Earths, 28, 747-751. 

Saito, M. Fujitani, T Takeuchi, M. Watanabe, T. Development of Copper/Zinc Oxide-Based Multicomponent Catalysts for Methanol Synthesis from Carbon dioxide and Hydrogen. App/. CatalA. Gen. 1996, 138, 311-318. 

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