Selective product crystallization as a new catalyst recycling tool in homogeneous transition metal catalysis exemplified by the conversion of oleochemicals

选择性产物结晶作为均相过渡金属催化中新的催化剂回收工具，以油脂化学品的转化为例

• 批准号: 424535516
• 负责人: Dr. Thomas Seidensticker
• 金额: --
• 依托单位: Lehrstuhl für Technische Chemie (TC)
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2019
• 资助国家: 德国
• 起止时间: 2018-12-31 至 2022-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/424535516?language=en
• 关键词: Selective; product; crystallization; new; catalyst

New and sustainable ways to biopolymers are in focus of attention in times of global raw material change. In particular, raw materials from natural fats and oils have structural properties that make them interesting for the production of certain polymers that were previously petrochemically accessible only. The conversion of these oleochemicals into the necessary polymer precursors is particularly efficient with the aid of homogeneous transition metal catalysts. The many advantages of this form of catalysis, such as high selectivity, mild reaction conditions and reaction control in a homogeneous phase, are countered by the critical task of efficient separation of products and catalyst in the downstream. However, separation is crucial with regard to an ecological and economical viable application: On the one hand, to obtain products free of heavy metal contamination. On the other hand, to enable recycling of the usually expensive precious metal catalysts. However, this task has not yet been solved for the very interesting class of polymer precursors from oleochemicals produced via homogeneous catalysts. In principle, processes for the separation of homogeneous mixtures are based on the different molecular properties of the substances contained, e.g. boiling points (distillation), relative solubilities (extraction), or molecular sizes (nanofiltration). For the discussed substance class, however, there are no sufficient differences between catalyst and product in their properties used in the established separation processes, which is why the desired separation efficiency is not achieved. As a result, scaling to industrial scale presently fails due to the unsolved separation task, although great interest and potential has already been shown. Interestingly, a separation due to different melting points has not yet been considered.The aim of the present research project is therefore to use crystallization for the first time as a separation and recycling process for homogeneous catalysts and thus to fundamentally demonstrate its potential for the existing separation task by means of a model reaction. An interdisciplinary approach is required in order to optimally adapt the respective parameters of reaction and crystallization to each other and to detect mutual interactions as early as possible. By doing so, the combination of homogeneous catalysis and cooling crystallization succeeds to selectively separate the product as a pure solid from the reaction mixture. At the same time, the homogeneous catalyst remains in solution and can be reused after solid/liquid separation has been completed, thus achieving its recycling. These fundamental investigations serve the long-term goal of integrating the homogeneous catalytic synthesis of these valuable, sustainable polymer precursors into an efficient and industrially applicable process.

在全球原材料变化的时代，生物聚合物的新的和可持续的方法成为关注的焦点。特别是，来自天然脂肪和油的原材料具有结构特性，使它们对生产以前只能通过石油化学方法获得的某些聚合物感兴趣。借助于均相过渡金属催化剂，将这些油脂化学品转化为必要的聚合物前体特别有效。这种形式的催化的许多优点，如高选择性、温和的反应条件和在均相中的反应控制，被在下游有效分离产物和催化剂的关键任务所抵消。然而，分离对于生态和经济可行的应用至关重要：一方面，获得无重金属污染的产品。另一方面，能够回收通常昂贵的贵金属催化剂。然而，对于通过均相催化剂从油脂化学品生产的非常有趣的一类聚合物前体，该任务尚未解决。原则上，用于分离均匀混合物的方法基于所含物质的不同分子性质，例如沸点（蒸馏）、相对溶解度（萃取）或分子大小（纳米过滤）。然而，对于所讨论的物质类别，在已建立的分离方法中使用的催化剂和产品在其性质上没有足够的差异，这就是为什么没有实现所需的分离效率。因此，尽管已经显示出极大的兴趣和潜力，但由于未解决的分离任务，目前未能按比例放大到工业规模。有趣的是，由于不同的熔点分离尚未被考虑，因此，本研究项目的目的是首次使用结晶作为均相催化剂的分离和回收过程，从而从根本上证明其通过模型反应的现有分离任务的潜力。为了使反应和结晶的各自参数相互适应并尽早检测相互作用，需要采用跨学科的方法。通过这样做，均相催化和冷却结晶的组合成功地从反应混合物中选择性地分离作为纯固体的产物。同时，均相催化剂保留在溶液中，在固/液分离完成后可以重复使用，从而实现其循环利用。这些基础研究服务于将这些有价值的、可持续的聚合物前体的均相催化合成整合到一个高效的、工业上适用的过程中的长期目标。