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不饱和烃类化合物的羰基化反应是指在过渡金属催化剂存在条件下, 将一氧化碳(CO)分子以羰基的形式插入到烯烃(或者炔烃)与不同的亲核试剂中, 合成更高附加值化学品的转化过程. 本文综合评述了羰基化反应合成高附加值化学品的重要性, 介绍了几种不同类型的羰基化反应(氢甲酰化反应、 氢酯化反应、 氢酰胺化反应和氢羧基化反应)在发展新型催化剂体系及高效合成目标产物方面的研究进展, 并对羰基化反应存在的问题及未来发展方向和趋势进行了展望. 相似文献
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正CO加氢高温高压制备高级烃类是一种重要的煤间接液化技术(又称费托反应),被认为是一种替代石油、实现煤碳能源洁净高附加值利用的重要途径,受到学术界和工业界的极大关注~1。常用的费托合成催化剂有Ru、Co、Fe基等催化剂~2。Ni基催化剂虽然被广泛应用于加氢化工反应,但是由于其C―C偶联效率低,趋于催化生成低值的甲烷,因此Ni基催化剂又被称为甲烷化催化剂~3。当前,基于费托反应发展一条清洁、绿色的新型能 相似文献
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电催化生物质转化是以间歇式能源产生的电能驱动生物质电转化为高附加值有机化学品的过程,将其与水分解耦合能够产生高纯度氢气,具有有效降低化石燃料消耗、优化能源结构及解决环境问题的潜力.然而,由于生物质具有多个官能团及其转化反应涉及多个电子参与,电催化生物质转化面临着转化效率低、选择性差和稳定性不足等挑战.通过调控表面本征结构、构筑表面空位、引入表面杂原子和构建表面协同界面等一系列表界面化学工程对二维电催化材料进行设计和改性,实现对其表面电子结构和几何结构的优化,可以有效地改善二维材料的电转化效率、选择性和稳定性.本综述详细介绍了表界面化学改性二维材料电催化生物质转化的最新研究进展,总结了该研究领域存在的问题,并展望了其研究前景. 相似文献
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Over the past decades, advances in science and technology have greatly benefitted the society. However, the exploitation of fossil fuels and excessive emissions of polluting gases have disturbed the balance of the normal carbon cycle, causing serious environmental issues and energy crises. Global warming caused by heavy CO2 emissions is driving new attempts to mitigate the increase in the concentration of atmospheric CO2. Significant efforts have been devoted for CO2 conversion. To date, the electroreduction of CO2, which is highly efficient and offers a promising strategy for both storing energy and managing the global carbon balance, has attracted great attention. In addition, the electrosynthesis of value-added C2+ products from CO2 addresses the need for the long-term storage of renewable energy. Therefore, developing catalysts that function under ambient conditions to produce C2 selectively over C1 products will increase the utility of renewable feedstocks in industrial chemistry applications. Recently, great progress has been made in the development of materials for electrocatalytic CO2 reduction (ECR) toward C2+ products; however, some issues (e.g., low selectivity, low current efficiency, and poor durability) remain to be addressed. In addition, the elementary reaction mechanism of each C2+ product remains unclear, contributing to the blindness of catalyst design. In this regard, the development of proposed mechanisms of ECR toward C2+ products is summarized herein. The key to generating C2+ products is improving the chances of C―C coupling. Test conditions significantly influence the reaction path of the catalyst. Thus, three different paths that that are most likely to occur during ECR to C2+ products are proposed, including the CO, CO-COH, and CO-CO paths. In addition, typical material regulatory strategies and technical designs for ECR toward C2+ products (e.g. crystal facet modulation, defect engineering, size effect, confinement effects, electrolyzer design, and electrolyte pH) are introduced, focusing on their effects on the selectivity, current efficiency, and durability. The four strategies for catalyst design (crystal facet modulation, defect engineering, size effect, and confinement effect) primarily affect the selectivity of the ECR via adjustment of the adsorption of reaction intermediates. The last two strategies for technique design (electrolyzer design and electrolyte pH) contributing greatly toward improving the current efficiency than selectivity. Finally, the challenges and perspectives for ECR toward C2+ products and their future prospects are discussed herein. Therefore, breakthroughs in the promising field of ECR toward the generation of C2+ products are possible when these catalyst design strategies and mechanisms are applied and novel designs are developed. 相似文献