Enhanced Dehydrogenation of 2-Propanol via Surface Synergism of CuO@ Nanostructured Ceria Derived from Modified Ce-UiO-66

IF 2.3 4区化学 Q3 CHEMISTRY, PHYSICAL

Catalysis Letters Pub Date : 2025-09-18 DOI:10.1007/s10562-025-05161-y

Ahmed Abdo Hassan, Mostafa Farrag, Rabei M. Gabr, Mohamed I. Said

{"title":"Enhanced Dehydrogenation of 2-Propanol via Surface Synergism of CuO@ Nanostructured Ceria Derived from Modified Ce-UiO-66","authors":"Ahmed Abdo Hassan, Mostafa Farrag, Rabei M. Gabr, Mohamed I. Said","doi":"10.1007/s10562-025-05161-y","DOIUrl":null,"url":null,"abstract":"<div><p>Dehydrogenation of alcohols to ketones and hydrogen offers a green and sustainable procedure for H<sub>2</sub> production as a best alternative for clean fuel. Researchers are challenged today to develop catalysts that possess remarkable conversion as well as high selectivity towards alcohol dehydration. CuO modified, structured cerias were successfully synthesized by carbonization of Ce-UiO-66 at 400–600 °C. The synthesized materials were characterized by XRD, XPS, TGA, TEM, EDX and FTIR spectroscopy. Surface texture also was investigated through N<sub>2</sub> adsorption at (77 <sup>°</sup>K). The catalysts were posted towards the dehydrogenation of 2-propanol in the gas phase. The catalytic performance could easily be tested by varying the Cu/Ce ratio, calcination temperature, and catalyst loading. The optimized CuO/CeO<sub>2</sub> ratio exhibited > 99% conversion and 100% selectivity for both H<sub>2</sub> and acetone at 225 °C. The characterization results showed that the synergetic effect between Cu<sup>2+</sup> and ceria existed and thus strengthening H<sub>2</sub> production, meanwhile following acetone generation. Kinetic analysis was studied isothermally at different temperatures which reveals that the dehydrogenation of 2-propanol behaves as first-order kinetics. The data was extended to determine the rate constant and the apparent activation energy (E<sub>a</sub>), which was found to be 19.48 kJ/mole. We proceeded further to compute ∆H, ∆S, and ∆G values. The values that confirm the thermodynamic spontaneity of the dehydrogenation pathway. The surface synergisms caused by the CuO modification, which increase the ratio of Ce(III) to Ce(IV) atoms and cause the creation of Cu(I) and Cu(II) sites, are responsible for the catalytic performance of the produced catalysts. Consequently, the CuO modification promotes the dehydrogenation pathway which needs these basic sites. Therefore, it is reasonable to propose that the most likely cause of the observed CuO enhancement of 2-propanol dehydrogenation is the improved production of Ce(III)/Ce(IV) and Cu(I)/Cu(II) redox couples. A Langmuir Hinshelwood mechanism was suggested, which included adsorbed IPA, H<sub>2</sub>, acetone, and isopropoxide into the site balance and supposed that the removal of the initial atom was the step that determined the reaction rate.</p><h3>Graphical Abstract</h3><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":508,"journal":{"name":"Catalysis Letters","volume":"155 10","pages":""},"PeriodicalIF":2.3000,"publicationDate":"2025-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Catalysis Letters","FirstCategoryId":"92","ListUrlMain":"https://link.springer.com/article/10.1007/s10562-025-05161-y","RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"CHEMISTRY, PHYSICAL","Score":null,"Total":0}

引用次数: 0

Abstract

Dehydrogenation of alcohols to ketones and hydrogen offers a green and sustainable procedure for H₂ production as a best alternative for clean fuel. Researchers are challenged today to develop catalysts that possess remarkable conversion as well as high selectivity towards alcohol dehydration. CuO modified, structured cerias were successfully synthesized by carbonization of Ce-UiO-66 at 400–600 °C. The synthesized materials were characterized by XRD, XPS, TGA, TEM, EDX and FTIR spectroscopy. Surface texture also was investigated through N₂ adsorption at (77 ^°K). The catalysts were posted towards the dehydrogenation of 2-propanol in the gas phase. The catalytic performance could easily be tested by varying the Cu/Ce ratio, calcination temperature, and catalyst loading. The optimized CuO/CeO₂ ratio exhibited > 99% conversion and 100% selectivity for both H₂ and acetone at 225 °C. The characterization results showed that the synergetic effect between Cu²⁺ and ceria existed and thus strengthening H₂ production, meanwhile following acetone generation. Kinetic analysis was studied isothermally at different temperatures which reveals that the dehydrogenation of 2-propanol behaves as first-order kinetics. The data was extended to determine the rate constant and the apparent activation energy (E_a), which was found to be 19.48 kJ/mole. We proceeded further to compute ∆H, ∆S, and ∆G values. The values that confirm the thermodynamic spontaneity of the dehydrogenation pathway. The surface synergisms caused by the CuO modification, which increase the ratio of Ce(III) to Ce(IV) atoms and cause the creation of Cu(I) and Cu(II) sites, are responsible for the catalytic performance of the produced catalysts. Consequently, the CuO modification promotes the dehydrogenation pathway which needs these basic sites. Therefore, it is reasonable to propose that the most likely cause of the observed CuO enhancement of 2-propanol dehydrogenation is the improved production of Ce(III)/Ce(IV) and Cu(I)/Cu(II) redox couples. A Langmuir Hinshelwood mechanism was suggested, which included adsorbed IPA, H₂, acetone, and isopropoxide into the site balance and supposed that the removal of the initial atom was the step that determined the reaction rate.

Graphical Abstract

查看原文本刊更多论文

改性Ce-UiO-66制备的CuO@纳米氧化铈表面协同作用增强2-丙醇脱氢

醇脱氢制酮和氢为氢气生产提供了一种绿色和可持续的过程，是清洁燃料的最佳替代品。研究人员今天面临的挑战是开发催化剂，具有显著的转化，以及对酒精脱水的高选择性。以Ce-UiO-66为原料，在400-600℃下碳化，成功合成了CuO修饰的结构铈。采用XRD、XPS、TGA、TEM、EDX和FTIR等方法对合成材料进行了表征。在（77°K）条件下通过N2吸附考察了其表面结构。催化剂用于2-丙醇气相脱氢。通过改变Cu/Ce比、煅烧温度和催化剂负载可以很容易地测试催化性能。在225℃条件下，优化后的CuO/CeO2对H2和丙酮的转化率为99%，选择性为100%。表征结果表明，Cu2+与铈存在协同作用，促进H2的生成，同时促进丙酮的生成。在不同温度下对2-丙醇脱氢反应进行了等温动力学分析，结果表明2-丙醇脱氢反应为一级动力学。对数据进行了扩展，确定了反应速率常数和表观活化能（Ea）为19.48 kJ/mol。我们进一步计算∆H，∆S和∆G值。这些值证实了脱氢途径的热力学自发性。CuO修饰引起的表面协同作用，增加了Ce（III）与Ce（IV）原子的比例，并导致Cu(I)和Cu（II）位点的产生，是产生催化剂催化性能的原因。因此，CuO修饰促进了需要这些碱基的脱氢途径。因此，我们有理由认为，2-丙醇脱氢过程中CuO增强的最可能原因是Ce(III)/Ce（IV）和Cu(I)/Cu（II）氧化还原对生成的提高。提出了一种Langmuir Hinshelwood机制，该机制包括将IPA、H2、丙酮和异丙醇吸附到位点平衡中，并认为去除初始原子是决定反应速率的步骤。图形抽象

本文章由计算机程序翻译，如有差异，请以英文原文为准。

求助全文

约1分钟内获得全文求助全文

来源期刊

Catalysis Letters 化学-物理化学

CiteScore

5.70

自引率

3.60%

发文量

327

审稿时长

1 months

期刊介绍： Catalysis Letters aim is the rapid publication of outstanding and high-impact original research articles in catalysis. The scope of the journal covers a broad range of topics in all fields of both applied and theoretical catalysis, including heterogeneous, homogeneous and biocatalysis. The high-quality original research articles published in Catalysis Letters are subject to rigorous peer review. Accepted papers are published online first and subsequently in print issues. All contributions must include a graphical abstract. Manuscripts should be written in English and the responsibility lies with the authors to ensure that they are grammatically and linguistically correct. Authors for whom English is not the working language are encouraged to consider using a professional language-editing service before submitting their manuscripts.