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Apesteguı́a, C.R.; Rites, B. De; Miseo, S.; Soled, S.

doi:10.1023/a:1018987900456

Cited by 31 publications

(52 citation statements)

References 7 publications

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“…Residual potassium in all dry samples was less than 0.1 wt.% before alkali impregnation. The controlled pH coprecipitation technique produces uniform precipitates, which lead, after thermal treatment, to mixed metal oxides with high surface area and intimate contact between components (8). CuZnAlO x samples were prepared using the same procedures as for CuMgCeO x , except that the pH was held at 7.0 and the dried powders were treated in flowing air at 623 K for 4 h (11,12).…”

Section: Catalyst Synthesismentioning

confidence: 99%

“…Specifically, we describe the synthesis procedures, catalyst structural characterization data, and surface and catalytic properties for a class of materials based on K-modified CuMgCeO x (6)(7)(8). These K-CuMgCeO x catalysts are among the best reported catalysts for alcohol synthesis at low temperatures and pressures (6)(7)(8). MgObased solids also catalyze condensation reactions of alcohols and aldehydes with high activity and selectivity (9,10).…”

Section: Introductionmentioning

confidence: 99%

“…MgObased solids also catalyze condensation reactions of alcohols and aldehydes with high activity and selectivity (9,10). CuMgCeO x samples were prepared by controlled pH coprecipitation methods designed to maximize the number of Cu surface atoms and basic sites (8). Site titration and isotopic switch methods were used to determine the density and chemical properties of exposed Cu and basic sites.…”

Section: Introductionmentioning

confidence: 99%

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Isobutanol and Methanol Synthesis on Copper Catalysts Supported on Modified Magnesium Oxide

Ginés

Hilmen

et al. 1997

Journal of Catalysis

137

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Section: Catalyst Synthesismentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Isobutanol and Methanol Synthesis on Copper Catalysts Supported on Modified Magnesium Oxide

Ginés

Hilmen

et al. 1997

Journal of Catalysis

137

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“…The most studied catalysts for low-temperature higher alcohol synthesis are based on Cu and ZnO, often with Al 2 O 3 or Cr 2 O 3 as structural promoters that increase the surface area and prevent sintering [3±25]. Other Cu-based catalysts, such as K±Cu x Mg y CeO z [26,27], have recently been shown to catalyze the synthesis of isobutanol at low temperatures. Li±Pd/ZrO 2 ±MnO 2 ±ZnO catalysts show very high isobutanol synthesis productivity at high temperatures (>673 K) and pressures (>10 MPa) [28].…”

Section: Introductionmentioning

confidence: 99%

Synthesis of higher alcohols on copper catalysts supported on alkali-promoted basic oxides

Hilmen

Ginés

et al. 1998

Applied Catalysis A: General

102

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K±Cu y Mg 5 CeO x and Cs±Cu/ZnO/Al 2 O 3 are selective catalysts for the synthesis of alcohols from an H 2 /CO mixture at relatively low pressures and temperatures. CO 2 produced in higher alcohol synthesis and water±gas shift (WGS) reactions reversibly inhibits the formation of methanol and higher alcohols by increasing oxygen coverages on Cu surfaces and by titrating basic sites required for aldol-type chain growth steps. Inhibition effects are weaker on catalysts with high Cu-site densities. On these catalysts, the abundance of Cu sites allows reactants to reach methanol synthesis equilibrium and maintain a suf®cient number of Cu surface atoms for bifunctional condensation steps, even in the presence of CO 2 . The addition of Pd to K±Cu 0.5 Mg 5 CeO x weakens CO 2 inhibition effects, because Pd remains metallic and retains its hydrogenation activity during CO hydrogenation. Basic sites on Mg 5 CeO x are stronger than on ZnO/Al 2 O 3 and they are more ef®ciently covered by CO 2 during alcohol synthesis. K and Cs block acid sites that form dimethylether and hydrocarbons. Alcohol addition studies show that chain growth occurs predominantly by aldol-type addition of methanol-derived C 1 species to ethanol and higher alcohols, following the rules of base-catalyzed aldol condensations. The initial C±C bond formation required for ethanol synthesis, however, proceeds directly from CO, at least on K±Cu y Mg 5 CeO x catalysts. A detailed kinetic analysis shows that chain growth probabilities are very similar on K±Cu y Mg 5 CeO x and Cs±Cu/ZnO/Al 2 O 3 catalysts. The growth probabilities of C 1 chains to ethanol and of iso-C 4 chains to higher alcohols are much lower than for other chain growth steps. # 1998 Elsevier Science B.V.

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“…Both carbon atoms of methyl formate were labeled, indicating that it formed from two molecules of methanol. 1 H-*C-C-CH, 1 CH30H reactions were carried out in order to explore chain growth pathways leading to higher alcohols on base catalysts. In a typical experiment, the catalyst (1 8 mg) was charged into a gradientless batch reactor and reduced in 10 % H2 (balance He) at 623 K for 30 min.…”

Section: Kinetic Studies Of Alcohol Coupling Reactionsmentioning

confidence: 99%

Isobutanol-methanol mixtures from synthesis gas. Quarterly report, July 1 - September 30, 1996

Iglesia¹

1996

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Untitled

Cited by 31 publications

References 7 publications

Isobutanol and Methanol Synthesis on Copper Catalysts Supported on Modified Magnesium Oxide

Isobutanol and Methanol Synthesis on Copper Catalysts Supported on Modified Magnesium Oxide

Synthesis of higher alcohols on copper catalysts supported on alkali-promoted basic oxides

Isobutanol-methanol mixtures from synthesis gas. Quarterly report, July 1 - September 30, 1996

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