催化学报 ›› 2019, Vol. 40 ›› Issue (2): 192-203.DOI: 10.1016/S1872-2067(19)63270-5

• 论文 • 上一篇    下一篇

CuOx-CaCO3催化剂高效催化生物质乙酰丙酸甲酯制备γ-戊内酯

曹雪娟a, 刘淮a, 魏珺楠a, 唐兴a,b, 曾宪海a,b, 孙勇a,b, 雷霆宙c, 赵耿d, 林鹿a,b   

  1. a 厦门大学能源学院, 生物质清洁高值化利用厦门市重点实验室, 福建厦门 361102;
    b 福建省生物质清洁高值化技术工程研究中心, 福建厦门 361005;
    c 河南省生物质能源重点实验室, 河南郑州 450008;
    d 信阳师范学院化学化工学院, 河南信阳 464000
  • 收稿日期:2018-10-25 修回日期:2018-11-26 出版日期:2019-02-28 发布日期:2019-01-11
  • 通讯作者: 唐兴, 林鹿
  • 基金资助:

    国家自然科学基金(21676223,21706223,21776234,21606188);厦门大学校长基金(20720180084);福建省自然科学基金(2018J01017);福建省高校青年自然基金重点项目(JZ160398);厦门大学能源学院能源发展基金(2017NYFZ02).

Effective production of γ-valerolactone from biomass-derived methyl levulinate over CuOx-CaCO3 catalyst

Xuejuan Caoa, Huai Liua, Junnan Weia, Xing Tanga,b, Xianhai Zenga,b, Yong Suna,b, Tingzhou Leic, Geng Zhaod, Lu Lina,b   

  1. a Xiamen Key Laboratory of Clean and High-valued Utilization for Biomass, College of Energy, Xiamen University, Xiamen 361102, Fujian, China;
    b Fujian Engineering and Research Center of Clean and High-valued Technologies for Biomass, Xiamen 361005, Fujian, China;
    c Henan Key Lab of Biomass Energy, Zhengzhou 450008, Henan, China;
    d College of Chemistry and Chemical Engineering, Xinyang Normal University, Xinyang 464000, Henan, China
  • Received:2018-10-25 Revised:2018-11-26 Online:2019-02-28 Published:2019-01-11
  • Contact: S1872-2067(19)63270-5
  • Supported by:

    This work was supported by the National Natural Science Foundation of China (21676223, 21706223, 21776234, 21606188), the Fundamental Research Funds for the Central Universities (20720180084), the Natural Science Foundation of Fujian Province of China (2018J01017), the Education Department of Fujian Province (JZ160398) and the Energy development Foundation of Energy College, Xiamen University (2017NYFZ02).

摘要:

γ-戊内酯(GVL)在燃料和化学品上有着巨大的潜在利用价值,如何从生物质木质纤维素出发经济地制备GVL广受关注.目前已有大量的研究致力于利用不同氢源从乙酰丙酸及其酯类催化加氢制备GVL的催化体系.过去的数年里,外加氢气条件下的乙酰丙酸及其酯类加氢制备GVL已经得到了广泛的研究.考虑到液体醇使用和管理相比于氢气更为安全便捷,而且醇类如甲醇、乙醇都是可以从生物质制备的绿色环保的溶剂,利用醇类通过Meerwein-Ponndorf-Verley(MPV)还原作为生物质催化加氢过程中的的溶剂和氢供体已经引起了人们的浓厚兴趣.在脂肪醇中,甲醇的还原势能最高,在MPV还原里的效果不如其他醇,但可以通过甲醇重整制氢的方式来供氢.此外,乙酰丙酸甲酯(ML)可以通过甲醇中酸催化醇解碳水化合物制得,因此可以尝试将碳水化合物醇解制备ML;甲醇重整制氢以及ML加氢结合起来,从而省去繁琐且能耗较大的ML分离步骤.腐殖质的存在和固体催化剂在甲醇中的稳定性是上述两步法策略的最大挑战.
本文通过草酸凝胶共沉淀法首次制备了(n)CuOx-CaCO3n为Cu/Ca摩尔比)双功能催化剂,用于以甲醇为原位氢源,从生物质ML一锅制备GVL反应中.经筛选,(3/2)CuOx-CaCO3催化制备GVL的得率高达95.6%.利用各种表征手段分析了催化剂使用前后的组成和结构变化.结果显示,新制的CuOx-CaCO3催化剂中即可检测到Cu+的存在,且在使用过程中CaCO3可以有效阻止二价铜在氢气氛围下被完全还原成单质铜.对于该体系中的ML加氢,亚铜有着比单质铜更佳的催化性能.循环实验表明,(3/2)CuOx-CaCO3至少可以连续稳定使用8次,其催化活性没有明显损失.此外,在纤维素醇解产物中存在腐殖质的情况下,(3/2)CuOx-CaCO3催化剂仍能够有效催化纤维素醇解得到的ML加氢制备GVL.因此可以利用这个高效廉价的催化剂开发一种便捷的一锅两步法从木质纤维素生物质制备GVL,即将酸催化的纤维素醇解、甲醇重整、ML在甲醇溶剂中加氢三者整合起来.

关键词: γ-戊内酯, 乙酰丙酸甲酯, 加氢, 甲醇重整, 纤维素甲醇解

Abstract:

The production of γ-valerolactone (GVL) from lignocellulosic biomass has become a focus of research owing to its potential applications in fuels and chemicals. In this study, (n)CuOx-CaCO3 (where n is the molar ratio of Cu to Ca) compounds were prepared for the first time and shown to function as efficient bifunctional catalysts for the conversion of biomass-derived methyl levulinate (ML) into GVL, using methanol as the in-situ hydrogen source. Among the catalysts with varied Cu/Ca molar ratios, (3/2)CuOx-CaCO3 provided the highest GVL yield of 95.6% from ML. The incorporation of CaCO3 with CuO resulted in the formation of Cu+ species in a CuOx-CaCO3 catalyst, which greatly facilitated the hydrogenation of ML. Notably, CuOx-CaCO3 also displayed excellent catalytic performance in the methanolysis products of cellulose, even in the presence of humins. Therefore, a facile two-step strategy for the production of GVL from cellulose could be developed over this robust and inexpensive catalyst, through the integration of cellulose methanolysis catalyzed by sulfuric acid, methanol reforming, and ML hydrogenation in methanol medium.

Key words: γ-Valerolactone, Methyl levulinate, Hydrocyclization, Methanol reforming, Cellulose methanolysis