The condensation of ethanol to 1‐butanol in the presence of different catalyst systems based on a Pd dehydrogenating/hydrogenating component and magnesium hydroxide‐derived materials as basic ingredient was studied in a fixed‐bed reactor. The metal was incorporated by wetness impregnation, and the resulting material was then reduced in situ with hydrogen at 573 K for 1 h before reaction. The bifunctional catalysts were tested in a fixed‐bed reactor operated in the gas phase at 503 K and 50 bar with a stream of helium and ethanol. A bifunctional catalyst supported on a synthetic composite based on Mg and high surface area graphite (HSAG) was also studied. Improved catalytic performance in terms of selectivity towards 1‐butanol and stability was shown by the Pd catalyst supported on the Mg–HSAG composite after thermal treatment in helium at 723 K, presumably due to the compromise between two parameters: adequate size of the Pd nanoparticles and the concentration of strongly basic sites. The results indicate that the optimal density of strongly basic sites is a key aspect in designing superior bifunctional heterogeneous catalyst systems for the condensation of ethanol to 1‐butanol.

中文翻译：

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在双功能Pd / Mg和Pd / Mg-碳催化剂上将生物乙醇连续气相冷凝为1-丁醇

在固定床反应器中研究了在基于钯脱氢/加氢组分和氢氧化镁衍生材料作为基本成分的不同催化剂体系存在下，乙醇与1-丁醇的缩合反应。通过湿法浸渍来掺入金属，然后在反应之前用573 K的氢气原位还原所得的材料1小时。双功能催化剂在固定床反应器中进行了测试，该反应器在503 K和50 bar的气相中在氦气和乙醇气流下运行。还研究了负载在基于镁和高表面积石墨（HSAG）的合成复合材料上的双功能催化剂。在723 K的氦气中热处理后，负载在Mg-HSAG复合材料上的Pd催化剂显示出对1-丁醇的选择性和稳定性方面改善的催化性能，大概是由于两个参数之间的折衷：Pd纳米粒子的足够大小和强碱性位点的浓度。结果表明，强碱性位点的最佳密度是设计用于乙醇缩合为1-丁醇的高级双功能多相催化剂体系的关键方面。