Influence of N- and O-containing heteroatoms on the continuous desulfurization of heavy oils and liquid fuels using catalytic oxidation of organic compounds with aqueous polyoxometalate solutions

基于我们对原位产物分离（ECODS）液体燃料萃取-氧化脱硫的成功初步研究，后续项目的总体目标是将先前开发的技术扩展到燃料中更多杂原子的分离，并从根本上了解它们对脱硫的影响。关于新开发方法的技术实施，两个反应步骤（底物被氧氧化，催化剂水溶液被氧负载）的空间分离也应该在一个连续的过程中进行。在之前非常成功的项目中，发现了一种高效的氧化萃取脱硫体系（HPA-5水溶液），作为迄今为止工业上多相催化加氢脱硫的替代方法。我们系统的优点是所有的脱硫产物（硫酸、磺酸、羧酸）都是从有机相原位提取到水相的。这一点既适用于模型油，也适用于真实油。继续提案的关键是我们新开发的用于液体燃料原位脱硫的反应体系（HPA-5水溶液）具有有效脱硫芳香和脂肪族体系的潜力。然而，分解产物在水相的积累已被发现抑制催化剂体系。这可以通过添加草酸来避免。基于这些有希望的结果，有必要进一步研究（如继续提案中所计划的）燃料中含氮和含氧成分对脱硫的影响。因此，例如，含n的燃料成分，如吲哚或喹啉类，可能对我们的催化剂系统有类似的激活作用，这可能对我们概念的技术实施有重大贡献。因此，在继续提案的过程中，需要从根本上研究各种含N和含o组分对液体燃料氧化萃取脱硫的影响。为此目的，应研究和了解在适当模型物质基础上的影响，例如脱硝对燃料脱硫的影响。这种方法有可能进一步增强我们新开发的脱硫技术，理想情况下，将其与从液体燃料中去除更多杂原子结合起来。

Based on our successful preliminary investigations on the extractive-oxidative desulfurization of liquid fuels with in-situ product separation (ECODS), the overall goal of the follow-up project is to extend the previously developed technology to the separation of further heteroatoms from fuels and to fundamentally understand their effect on desulfurization. With regard to a technical implementation of the newly developed method, a spatial separation of the two reaction steps (substrate oxidation by oxygen, loading of the aqueous catalyst solution with oxygen) should also be carried out in a continuous process.In the previous, very successful project, an efficient system for oxidative-extractive desulfurization (aqueous HPA-5 solution) was found as an alternative to the hitherto industrial process of heterogeneously catalyzed hydrodesulfurization. The advantage of our system is that all desulfurization products (sulfuric acid, sulfonic acids, carboxylic acids) are extracted in-situ from the organic to the aqueous phase. This could be shown for model oils as well as for real oils.Essential for the continuation proposal is that our newly developed reaction system (aqueous HPA-5 solution) for the in-situ desulfurization of liquid fuels has the potential to efficiently desulfurize both aromatic and aliphatic systems. However, accumulation of decomposition products in the aqueous phase has been found to inhibit the catalyst system. This could be circumvented by the addition of oxalic acid. Based on these promising results, further investigations (as planned in the continuation proposal) are necessary with regard to the influence of N- and O-containing components in fuels on desulfurization. Thus, for example, N-containing fuel components such as indoles or quinolines could have a similar activating effect on our catalyst system, which could significantly contribute to the technical implementation of our concept. Therefore, in the continuation of the proposal, the influence of various N- and O-containing components on the oxidative-extractive desulfurization of liquid fuels should be fundamentally investigated. For this purpose, the influence on the basis of suitable model substances, e.g. the denitrification effect on the desulfurization of fuels should be investigated and understood. This approach has the potential to further enhance our newly developed desulfurization technology and, ideally, to combine it with the removal of further heteroatoms from liquid fuels.