At the 29th China Plastic Recycling and Regeneration Conference in ChinaReplis2024, Jiang Gangwen, co-founder/marketing director of Yuantian Biotechnology (Tianjin) Co., Ltd., gave a presentation on the theme of "Rb PET Plastic Enzymatic Regeneration and Industrialization".

1. Core Business Model

Yuantian Biotechnology is a company mainly engaged in the research and commercial application of enzymatic regeneration technology for waste PET plastics. The core business model is to recycle various types of waste PET materials (polyester fabrics, beverage bottles, packaging tapes, etc.) from upstream, then crush and preprocess them, and add them to the waste PET catalytic solution for degradation through fermentation to produce PTA and MEG monomers through crystallization and distillation. The monomer products can then be polymerized to obtain new PET particles (reborn PET, rb PET), which are then supplied downstream for further use in the production of food packaging, textile fibers, engineering materials, and optical devices, achieving infinite recycling of PET plastics.

2. 4 major technological highlights

Yuantian Biotechnology is the first PET enzymatic regeneration company in China, and its technical characteristics can be summarized into four points:
Firstly, the source of raw materials is wide. PET polyester, as the main raw material for beverage bottles and polyester fibers, is one of the plastics with the highest recycling rate in the industry. The most basic characteristic of biological enzymes is strong selectivity, specifically targeting PET degradation without reacting with other high molecular impurities;
Secondly, the reaction conditions are mild and can be carried out at room temperature and pressure;
Thirdly, the process is simple and can directly obtain monomeric PTA;
Fourthly, the single unit production is high. Since its establishment in 2022, Yuantian Biotechnology has built the first 1.5m ³ full process process process unit in China, achieving the release of 300 tons/year rPTA product capacity. In addition, the team is currently building a 20m ³ production line, which is expected to be completed in the third quarter of 2025. The rPTA production capacity can reach 3000 tons per year, with an output value of 50 million yuan.

3. Four steps towards industrialization

The core of Yuantian Biotechnology's industrialization of rb PET enzymatic regeneration lies in four breakthroughs:
Firstly, single enzyme dual function PET, as a bulk plastic product, would incur high costs if subjected to dual enzyme hydrolysis. However, Yuantian Biotechnology utilizes single enzyme dual function depolymerization technology to obtain two monomers, PTA and MEG, through a single enzyme hydrolysis, simplifying the PET enzymatic hydrolysis process and reducing costs.
Secondly, according to the theory of PET enzyme W156 swing regulation, through structural analysis and molecular simulation of PET enzyme, it was found that an important reason for the insufficient activity of wild enzymes is that the micro surface structure of the enzyme has a swing structure similar to a switch gate. By using W156 swing control technology, the door was transformed into a normally open state, significantly improving enzymatic hydrolysis efficiency.
Thirdly, PET enzyme tertiary structure AI reassembly is used to achieve secondary structure disassembly and tertiary structure reassembly from various PET enzyme sources through AI recombination, thereby forming a PET enzyme recombinant library that can achieve excellent enzyme activity near room temperature.
Fourthly, the development of low-cost new and simple processes is also the latest work done by Yuantian Biotechnology on the industrialization path. Through process updates, it achieves the recycling of raw materials and significantly reduces costs.

4. r PET industry technological innovation

At present, both domestically and internationally, the recycling and regeneration of PET mainly rely on thermophysical methods. However, the current recycling process cannot avoid PET performance degradation, making it difficult to recycle and reuse multiple times. Ultimately, it is often buried or incinerated, causing serious pollution to the environment.
Yuantian Biotechnology focuses on rPTA enzymatic production and the industrialization of rb PET at the 10000 ton level. Through technology integration and innovation such as enzyme molecule directed modification, enzyme stabilization technology, and biocatalytic process enhancement, it has achieved low-cost ton fermentation preparation of more than 10 enzyme preparations and large-scale production of high value-added biochemical products, providing new ideas for PET recycling.
From 2024 to 2026, the company plans to promote the production and construction of 3-30-20000 tons of rPTA products per year. It plans to process 30000 tons/year of waste textiles and convert them all into rb PET slices of the same quality as native PET for the production of clothing and plastic bottle products.