Enzymatic deconstruction of polyester textiles

如果我们要将目前的线性纺织经济转变为循环经济，减少对化石原料的依赖，就需要回收使用寿命结束的聚酯的新方法。聚酯是一种聚合物，通过化学键将构建块链连接在一起；在这种情况下，它们是酯键。天然聚合物在所有生命王国中都很常见，对于每一种天然聚合物，都存在一种天然酶，可以将其分解成其组成的构件。这些解构酶赋予生命循环性；构建块可以重复使用，而不会浪费。该项目将开发基于酶的技术，将废弃的涤纶纺织品分解为化学构建块，以便随后在循环生物经济中重复使用。我们将开发强大的酶，可以分解废旧纺织品中最常用的聚酯聚对苯二甲酸乙二醇酯(PET)，耐受这种原料带来的挑战，即它的韧性以及染料和添加剂的存在。我们的研究将确定使用酶将废旧纺织品中的PET分解成一汤简单的积木，然后再转化为新的聚酯的可行性，从而使现有的线性经济循环，并减少从化石燃料化学品生产原始PET的需要。目前的聚酯-主要是饮料瓶和食品包装-的酶回收方案依赖于能源密集型的预处理制度来降低聚合物的韧性，以便使其被当前性能最好的酶分解。涤纶纺织品对酶的解构提出了进一步的潜在挑战，因为它们含有可能阻碍酶活性的染料和其他添加剂。最终，行业采用基于酶的技术来分解聚酯纺织品将需要对该技术进行彻底的评估，包括在实验室规模的生物反应器中进行概念验证研究，以模拟拟议的工业应用。我们的项目将在三个相关的工作包中解决这些挑战，每个工作包都由一个影响咨询小组提供指导。我们将使用优化酶性能和绿色、物理化学前处理相结合的方法来克服坚韧聚酯对酶解构的抵抗力。我们将测试我们设计的酶与添加剂、染料和溶剂的兼容性，以选择最适合涤纶织物解构的酶。我们将在实验室规模的生物反应器中将我们最强大的酶应用于经过适当处理的废涤纶纺织品，以评估扩大酶解构技术的潜力和局限性。在整个过程中，我们将通过瓶子联盟和Biomimicry Institutes的分解设计项目与全球研究社区接触。我们还将通过与英国自行车服装品牌Endua的合作，在纺织品价值链上与英国企业的需求建立协同效应。在项目结束时，我们将与我们的项目合作伙伴和其他行业利益相关者举办研讨会，展示上述研究的结果，并为未来应用酶解聚酯布提供技术开发路线图的发展提供信息。

Novel means of recycling end-of-life polyesters are required if we are to convert the current, linear textile economy into a circular one with a reduced reliance on fossil-based feedstocks.Polyesters are a type of polymer, chains of building blocks linked together by chemical bonds; in this case, they are ester bonds. Natural polymers are commonplace in all kingdoms of life, and for every natural polymer, there exists a natural enzyme that can deconstruct it back into its constituent building blocks. These deconstructing enzymes give circularity to life; the building blocks are reused with nothing going to waste.This project will develop enzyme-based technology for the breakdown of waste polyester textiles into their chemical building blocks for subsequent reuse in a circular bioeconomy. We will develop robust enzymes that can deconstruct the most commonly-used polyester polyethylene terephthalate (PET) in waste textiles, tolerating the challenges that this feedstock poses, namely its toughness and the presence of dyes and additives. Our research will establish the feasibility of using enzymes to deconstruct the PET in waste textiles into a soup of simple building blocks for conversion back into new polyesters, thus circularising the existing linear economy, and reducing the need to produce virgin PET from fossil-fuel based chemicals. Current schemes for enzymatic recycling of polyesters - predominantly beverage bottles and food packaging - rely upon energy-intensive pre-treatment regimes to reduce the toughness of the polymer in order for it to be deconstructed by the current best-performing enzymes. Polyester textiles present further potential challenges for enzymatic deconstruction in that they contain dyes and other additives that may impede the activity of enzymes. Ultimately, industry's adoption of enzyme-based technology for deconstruction of polyester textiles will require thorough assessments of the technology, including proof-of-concept studies in laboratory-scale bioreactors that mimic the proposed industrial application.Our project will address these challenges in three related work packages, at each point guided by input from an impact advisory group. We will use a combined approach of optimising both enzyme performance and green, physicochemical textile pre-treatment to overcome the resistance of tough polyesters to enzymatic deconstruction. We will test the compatibility of our engineered enzymes with additives, dyes and solvents to select those enzymes that are best suited to polyester textile deconstruction. We will apply our most robust enzymes to appropriately pretreated waste polyester textiles in laboratory-scale bioreactors to evaluate the potential and limitations of scaling up the enzymatic deconstruction technology. Throughout, we will engage with the global research community through the BOTTLE consortium and through Biomimicry Institutes' Design for Decomposition project. We will also work to build synergy with the requirements of UK businesses in the textiles value chain through our partnership with Endura, a UK cycling clothing brand.At the end of the project, we will hold workshops with our project partners and other industrial stakeholders, to showcase the outcomes from the above study and to inform the development of a technology development roadmap for future application of enzymatic polyester textile deconstruction.