A new series of alumina supported nickel (8% w/w) catalysts, modified with promoters, La₂O₃, CeO₂, ZrO₂, MgO and TiO₂, highly active for the conversion of ethanol to butanol and higher alcohols, at 200°C-220°C, in batch mode, under autogenous pressure, has been investigated. XRD and XPS results indicate the presence of metallic Ni and Ni aluminate as the active phases. H₂-TPR studies reveal that the introduction of promoters improves nickel dispersion, reducibility and moderates the metal-support interactions.TPD of ammonia and CO₂ studies establish the strong influence of the promoter oxides on the strength and population of acidic and basic sites. Ethanol conversion at 200°C varies in a narrow range, 36-42%. CeO₂ and MgO modified catalysts display maximum selectivity towards butanol (48%) and higher alcohols, (81% and 75%) in comparison with the catalyst based on pristine alumina (28.9% and 40.5%). While the selectivity for butanol and higher alcohols is governed by the basicity of the catalysts, both metal function and basicity are required to drive ethanol conversion. Moderation of acidity helps in minimizing the formation of ethylene and other gaseous products. Analysis of used catalyst indicates that the structural and active phase characteristics are retained during use.

中文翻译：

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在Ni / MxOy-Al2O3（M = La，Ce，Zr，Mg和Ti）催化剂上将乙醇转化为高级醇：载体特性的影响

一系列新型的氧化铝负载的镍（8％w / w）催化剂，经促进剂La ₂ O ₃，CeO ₂，ZrO ₂，MgO和TiO ₂改性，在高温下可将乙醇转化为丁醇和高级醇在自生压力下，以间歇模式研究了200°C-220°C。XRD和XPS结果表明存在金属Ni和铝酸镍作为活性相。H ₂ -TPR研究表明，促进剂的引入改善了镍的分散性，还原性并缓和了金属与载体之间的相互作用。氨和CO ₂的TPD研究确定了助催化剂氧化物对酸性和碱性位点的强度和种群的强烈影响。200°C时的乙醇转化率在36-42％的狭窄范围内变化。与基于原始氧化铝的催化剂（28.9％和40.5％）相比，CeO ₂和MgO改性的催化剂显示出对丁醇（48％）和高级醇（81％和75％）的最大选择性。尽管丁醇和高级醇的选择性受催化剂的碱度支配，但金属官能度和碱度都需要驱动乙醇转化。适度的酸度有助于最小化乙烯和其他气态产物的形成。对用过的催化剂的分析表明，在使用过程中保留了结构和活性相特征。