Novel precious metal nanocatalyst made by biofabrication

贵金属催化剂是化学工业（氢化、氧化、合成）、环境（汽车催化剂、燃料电池）和医学（金属纳米颗粒）许多过程的关键。一般来说，不同的催化剂用于不同的工艺。近年来，双金属催化剂的潜在优势已得到重视，但这些类型的催化剂很难用传统方法制造，并且可能导致产品质量不稳定。作为正在进行的EPSRC项目的一部分，我们评估了利用细菌生物制造贵金属催化剂的潜力，而BBSRC的姊妹项目也在同时评估从废物中采购贵金属的潜力：这些项目共同展示了从废物中生物制造新型活性催化剂的“一站式”微生物方法。正在进行的EPSRC项目展示了一种基于Au和Pd的双金属催化剂的新方法。双金属催化剂是“新一代”：它们可以实现单金属催化剂无法实现的高选择性和反应。钯/金双金属催化剂尚未商业化，尽管催化剂行业正在努力实现这一目标。在一项短期的、内部资助的开发研究中，我们发现生物制造的Pd/Au双金属在典型的醇氧化中具有高选择性；选择性与高活性同时存在，这是商业单金属比较剂所不能达到的。这一点，以及生物制造系统的高可扩展性，促使了这次FoF竞标，其目的是促进和实现从台式演示到商业原型的过渡。对于后者，我们将利用合作带来的两种新型催化剂配方方法，即(a)支持碳球的金属纳米颗粒和(b)一种产生高度内聚细菌的新型固定化方法，该方法可以紧密地保持早熟金属纳米颗粒/双金属。我们将制造两种新材料的测试数量，并评估它们在已知商业相关氧化反应中的潜力。我们还将通过与FC专家的现有合作，测试新型“Bio-Pd/Au”作为燃料电池（FC）催化剂的潜力。使用(a)悬浮的金属化细菌细胞和(b)由两种新的附着方法制成的生物纳米催化剂，我们不仅将评估催化剂的总活性，还将评估催化剂在重复反应循环中的可重用性，特别强调耐久性和缺乏磨损，确保纳米催化剂的保留和与产品流的完全分离而不会碎裂。在技术工作的同时，业务发展将在两个专门从事业务发展的相关研究金的协助下进行，一个是希望发起新的合资企业的公司合作伙伴，另一个是将通过传播讲习班带头向市场观众组织传播活动的现有合作伙伴。随着知识产权申请的迫近，传播将没有障碍；事实上，一份手稿正在等待在不久的将来提交给《科学》杂志，预计还会有几次高调的传播。我们建议在项目的生命周期内实现这些目标

Precious metal catalysts are key to many processes in chemical industry (e.g. hydrogenations, oxidations, syntheses), environment (automotive catalysts, fuel cells) and medicine (metallic nanoparticles). In general different catalysts are used for different processes. Recently the potential benefits of being able to use bimetallic catalysts have been appreciated but these types of catalyst are difficult to make by conventional methods, and may give products of inconsistent quality.As part of an ongoing EPSRC project we evaluated the potential for using bacteria to biomanufacture precious metal catalysts, while a sister BBSRC project is, in parallel, evaluating the potential for sourcing precious metals from wastes: together these projects have demonstrated a 'one stop shop' microbial method to biomanufacturing new, active, catalysts from wastes. The ongoing EPSRC project has shown a new method to make a bimetallic catalyst based on Au and Pd. Bimetallic catalysts are 'next generation': they can achieve high selectivities and reactions that single metal catalysts cannot. Pd/Au bimetallic catalysts are not yet commercially available although the catalyst industry is working hard to achieve this goal. Within a short, internally-funded development study we showed high selectivity by biomanufactured Pd/Au bimetallic in a typical alcohol oxidation; the selectivity was accompanied by a high activity, neither of which were achieved by commercial single metal comparators. This, and the high scalability of biomanufacturing systems, prompted this FoF bid, the purpose of which is to facilitate and enable the transition from benchtop demonstration to commercial prototype. For the latter we will utilise two novel catalyst formulation methods brought by collaborations, namely (a) metallic nanoparticles supported on carbon spheres and (b) a novel immobilisation method yielding highly cohesive bacteria which hold the precoius metal nanoparticles/bimetallics tightly.We will manufacture test quantities of both new materials and evaluate their potential in oxidation reactions of known commercial relevance. We will also test the potential for the new 'Bio-Pd/Au' as a fuel cell (FC) catalyst via extant collaboration with a FC expert. . Using (a) suspended metallised bacterial cells and (b) bionanocatalyst made by the two new attachment methods we will evaluate not only total catalyst activity but catalyst re-usability in repeated reaction cycles, with particular emphasis on durability and lack of attrition, ensuring nanocatalyst retention and complete separation from the product stream without fragmentation. In parallel with the technical tasks business development will proceed with the assistance ot two associated Fellowships dedicated to business development, a company Partner who wishes to initiate a new joint venture, and a current Partner who will take the lead in organising dissemination activity to the market audience via a dissemination workshop. With IP filing imminent, there wil be no barrier to dissemination; indeed, a manuscript is awaiting submission to 'Science' in the immediate future, with several additional high profile disseminations anticipated. These we propose to achieve within the project's lifetime