BIOCHEMICAL ENGINEERING JOURNAL
·
2025
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IF 3.8
Zhi Wang,Jiaxing Zhang,Shengping You,Rongxin Su,Wei Qi
The extensive application of polyethylene terephthalate (PET) has led to severe environmental pollution. Enzymatic degradation provides a sustainable solution for PET recycling, but the limited hydrolytic activity of current PET hydrolases hinders its practical application. Here, we designed an Energy-Guided Accumulate Mutation Strategy (EGAMS) for the rational design of PET enzyme PHL7. By applying multiple rounds of evolution to enhance the degradation activity and thermostability of PHL7, we achieved the excellent PET degradation enzyme FlashPETase (PHL7 E148K/T158P/S184E/H185Y ) with 238.8% PET degradation activity of PHL7 and 82.93 °C melting temperature. FlashPETase completely degrades PET at 72 °C with an enzyme loading of 1.5 mg enzyme g PET −1 , without any substrate pretreatment or additional processing. As for PET substrates with high crystallinity, FlashPETase still performs well. Furthermore, molecular simulations revealed the structural mechanisms of FlashPETase’s enhanced activity and stability. In summary, the EGAMS protocol and the variants discussed in this work advance the fields of PET degradation and enzyme engineering, offering valuable insights for future research.
研究领域:
酶工程
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环境科学
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分子生物学
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DOI
高影响因子
CATALYSIS TODAY
·
2024
·
IF 5.2
Lin Gao,Zixian Jia,Lijiao Qin,Haocheng Sun,Xinwei Zhang,Baozhong Li,Xuehai Wang,Jiquan Liu,Jinbo Bai
The recovery of Zn/ZnO nanoparticles from spent alkaline batteries was studied. This catalyst was employed for glycolysis of polyethylene terephthalate (PET) to produce bis(2-hydroxyethyl) terephthalate (BHET). The reaction temperature, catalyst/PET ratio and reaction time were investigated. Under the optimal conditions of 190 ℃ and 2 hours, with a catalyst/PET ratio of 2 %, the PET conversion rate and BHET yield of this process were 99 % and 81 %, respectively. The experimental results show that the catalyst exhibits high catalytic activity, is easy to separate, and has good reusability. In addition, this catalyst can deal effectively with impurities and dyes present in waste PET. Finally glycolysis kinetic studies were conducted on the reaction of PET degradation, and the activation energy of 118.8 kJ·mol −1 were obtained.
研究领域:
材料科学
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环境科学
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化学工程
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产品关联
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2025
·
IF 7.2
Lu Li,Sihong Xu,Liang Jin,Wenxing Chen,Shichang Chen
It is essential to find a depolymerization system with good catalytic activity, easy operation, and high efficiency for the degradation of waste PET. The synergistic catalytic effect of 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) and zinc 2-ethylhexanoate (ZnEH) in PET glycolysis was investigated. Waste PET can be more efficient when completely degraded than single organocatalyst or zinc salt or previous DBU/Zn(OAc) 2 , and the yield of BHET reaches 84.1 % under optimal reaction conditions with the molar ratio of 2:1 of DBU to ZnEH and the weight ratio of 3:1 of EG to PET, the temperature of 180 °C and at 60 minutes. By combining experimental results with density functional theory (DFT) calculations, the synergistic enhancing degradation mechanism that generates hydrogen and coordination bonds is proposed. The purified depolymerization product of BHET was repolymerized to PET, delightfully the r-PET was almost identical to virgin PET.
研究领域:
材料科学
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环境科学
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化学工程
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产品关联
DOI
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
·
2024
·
IF 5.3
Ruiqi Zhang,Panpan Hao,Xiujie Cheng,Rana R. Neiber,Ling Wang,Yi Li,Junli Xu,Dongxia Yan,Qing Zhou,Jiayu Xin,Xingmei Lu
Ionic liquids (ILs) have been recognized as environmentally friendly and effective catalysts for poly (ethylene terephthalate) (PET) glycolysis. However, further investigation is required to gain a deeper understanding of the depolymerization mechanism. In this study, a series of experiments are conducted to investigate the impact of metallic and non-metallic ILs, containing diverse anions, on the interaction with PET surfaces. The findings indicate that the catalytic efficiency of IL is strongly correlated to the intensity of the interaction with PET. When the interface adhesion strength is more than twice that of PET/PET, the IL exhibits efficient catalytic properties in PET glycolysis. Therefore, an innovative approach involving the use of AFM for efficiently assessing highly effective IL catalysts is proposed. In addition, attenuated total reflectance Fourier transform-infrared (ATR-FTIR) spectroscopy and density functional theory (DFT) calculations further demonstrate the predominant interaction mechanism between ILs and PET. This research provides guiding significance for understanding the mechanism of PET glycolysis.
研究领域:
材料科学
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环境科学
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化学工程
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产品关联
DOI
高影响因子
POLYMER
·
2025
·
IF 4.5
Leqing He,Shuangbai Li,Chongpin Huang
In the context of composite materials that elude classification via conventional pretreatment methodologies such as crushing, granulating, and flotation—specifically within the domains of food packaging, construction materials, and engineering plastics—this research employed a one-step methanolysis-separation technique for the graded recycling of polypropylene (PP), polyethylene (PE), and polyethylene terephthalate (PET) in mixed plastics. Employing methanol as the reaction solvent, the benign and eco-friendly ionic liquid BMIMOH as the catalyst for the degradation of PET. PET was methanolized to produce dimethyl terephthalate (DMT), while PP and PE remained highly stable, were separated after the reaction, and subjected to subsequent recycling. The stability of PP and PE under methanolysis conditions was revealed through structural and thermodynamic analyses. Single-factor analysis and response surface methodology were employed to determine the optimal conditions for the methanolysis reaction. Additionally, the impact of different contents of PP and PE on the recovery of PET from the mixed plastics during the swelling-condensation process at high temperatures was explored. Under the optimal conditions, the yield of DMT was 94 % for the degradation of single PET, and when the ratio of PET in the mixed plastics was 50 %, the yield of DMT could still reach 90 %.
研究领域:
材料科学
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环境科学
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化学工程
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产品关联
DOI
高影响因子
EUROPEAN POLYMER JOURNAL
·
2025
·
IF 6.3
Zichen Wang,Yao Dai,Yumeng Wang,Peilu Zhang,Lin Zhou,Yuan Jiang,Ruoke Liu,Sarah Elfadil Ali Adam,Chao Sun,Xiaochun Chen
Polyethylene glycol terephthalate (PET) is widely utilized in industrial applications and everyday life. However, its extensive use has led to substantial environmental challenges. This study presents a highly active and selective [DBU][m-cresol] proton-ionic liquid (PIL)-immobilized ZIF-8 catalyst for PET resource utilization. Using just 15 mg of the ZIF-8@[DBU][m-cresol]-2 catalyst, PET degradation reached 97.72 %, while BHET conversion achieved 86.95 % within 60 min. The Zn 2+ ions in the catalyst decrease the electron density of the m-cresol carbocation, thus improving the nucleophilic substitution capability of [DBU][m-cresol]. The influence of catalyst dosage, the ethylene glycol-to-PET ratio, and temperature on degradation and conversion was investigated. After five cycles, the catalyst retained a degradation efficiency of 77.71%. In practical applications, testing on three commercial PET materials demonstrated degradation efficiencies exceeding 90%. DFT calculations and LC-MS analysis indicate that hydrogen bonding among ethylene glycol (EG), PET, and ZIF-8@[DBU][m-cresol] enhances PET’s electrophilicity, while Zn 2+ decreases the electron density of carbocations, thereby facilitating PET degradation. This work highlights the potential of proton-based ionic liquid-supported catalysts for efficiently converting PET waste into valuable resources.
研究领域:
环境科学
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材料科学
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化学工程
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DOI
高影响因子
PROCESS SAFETY AND ENVIRONMENTAL PROTECTION
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2024
·
IF 6.9
Zhongqing Shen,Zixian Jia,Kunpeng Yu,Jing Xie,Lijiao Qin,Lin Gao,Baozhong Li,Xuehai Wang,Jianzhong Yin
Depolymerization shows promise as a strategy for converting waste plastic into monomers that can be used for repolymerization. However, catalytic approaches would be more complex and expensive due to catalyst separation, recovery, and recycling. Here, we present a CO 2 -enhanced subcritical methanolysis method without catalyst that can generate monomer from poly(ethylene terephthalate)(PET). The synergistic effect of CO 2 on the subcritical methanolysis process for PET depolymerization was investigated including the CO 2 initial pressure, reaction temperature and reaction time. Under subcritical conditions, the optimal reaction parameters with PET conversion ratio of 100% and DMT yield of 79.1% are as follows: temperature of 220℃, methanol to PET mass ratio of 6:1 and reaction time of 50 min. Moreover, through the analysis of experimental data, it was concluded that the depolymerization reaction follows a first-order kinetics, with the reaction rate being 2–3 times faster than the traditional process. However, the apparent activation energy for both reactions is found to be similar, with values of 135.1 kJ·mol −1 and 146.2 kJ·mol −1 , respectively.
研究领域:
化学工程
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材料科学
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产品关联
DOI
高影响因子
GREEN CHEMISTRY
·
2024
·
IF 9.3
Fei Li,Xiaoqian Yao,Rong Ding,Yinan Bao,Qing Zhou,Dongxia Yan,Yi Li,Junli Xu,Jiayu Xin,Xingmei Lu
Glycolysis of waste polyethylene terephthalate (PET) is a green and high-value PET recovery approach, the product of which can be used as raw materials to prepare polyurethanes. Enhancing the conversion rate and monomer selectivity of PET glycolysis through the development of efficient catalysts is crucial for reducing both the energy consumption and operational costs associated with the process. In this study, a series of deep eutectic solvents (DESs) were synthesised based on L-proline (Pro) and its derivatives and used as catalysts for the glycolysis of PET using 1,4-butanediol (BDO). Under the optimized reaction conditions (5.0 g PET, 25.0 g BDO, 2 wt% Pro/Zn(Ac)2 catalyst, 210 °C, 15 min and atmospheric pressure), PET was degraded completely, and the yield of monomeric bis(4-hydroxybutyl)terephthalate (BHBT) reached 67.1%. Based on the results of in situ-IR, 1H NMR and density functional theory (DFT), the possible catalytic mechanism of DESs synergistically promoting PET depolymerization was proposed. Finally, aromatic-based polyurethane elastomers (PUEs) were prepared with PET glycolysis products bis(2-hydroxyethyl)terephthalate (BHET) and BHBT as chain extenders. Compared with the control group, the thermal and mechanical properties of aromatic-based PUEs were improved, which proved the feasibility of high value utilization of PET glycolysis products.
研究领域:
材料科学
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化学工程
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环境科学
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产品关联
DOI
高影响因子
ENVIRONMENTAL SCIENCE & TECHNOLOGY
·
2025
·
IF 11.3
Wenbin Guo,Zhengguang Shi,Xue Yu,Jingjing Duan
An important environmental issue is the pollution caused by poly(ethylene terephthalate) (PET) and the emitted monomers terephthalic acid (TPA) and ethylene glycol (EG). The TPA biodegradation pathway has been well documented for the microbial biodegradation and assimilation of PET; however, the PET biodegradation process by marine microorganisms via the EG biodegradation pathway is less understood. Here, we demonstrate how the marine bacteria Pseudomonas chengduensis BC1815’s membrane-anchored PET esterase (OF113_10420) breaks down PET. We also explain the characteristics of this enzyme and demonstrate that the strain assimilates PET via the EG biodegradation pathway. In addition to depolymerizing PET, PET esterase (OF113_10420) hydrolyzes BHET and MHET to generate EG more efficiently in alkaline circumstances. It has been discovered that P. chengduensis BC1815 cells exhibiting surface-displayed PET esterase (OF113_10420) have the potential to function as cell biocatalysts for the breakdown of PET. Additionally, we look into the microbial communities that have PET esterase linked to the EG biodegradation pathway, primarily those belonging to the phyla Proteobacteria and Actinobacteriota. Consequently, research on the microbial absorption and biodegradation of PET via the EG metabolism route increases our knowledge of the bioremediation of PET pollution in the marine environment and contributes to our understanding of the environmental destiny of PET pollutants in the marine environment.
研究领域:
环境科学
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微生物学
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生物化学
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产品关联
DOI
PubMed
高影响因子
BIOCHEMICAL ENGINEERING JOURNAL
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2024
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IF 3.7
Jiaojiao Sun,Yaxing Pang,Ziyi Lei,Bo OuYang,Wanxian Lai,Yonghua Wang,Dongming Lan
Advancing the efficiency of polyethylene terephthalate (PET) degradation is pivotal for sustainable and versatile PET recycling. In this study, we initially screened eight esterases , pinpointing Pyrobaculum calidifontis VA1 esterase (PCEST) as markedly effective in decomposing PET intermediate products. Building on this discovery, we engineered fusion proteins combining a robust cutinase (HRC) with PCEST, connected by flexible glycine-serine linkers. We further optimized the linker length, the sequential arrangement and the enzymatic conditions of the conjugated enzymes . Notably, the synergistic activity of the HRC-PCEST fusion protein significantly enhanced the breakdown of PET, thereby promising to streamline recycling processes. Collectively, this methodology not only propels the efficiency of PET degradation but also broadens the horizons for sustainable and versatile PET waste management protocols.
研究领域:
生物化学
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环境科学
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材料科学
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DOI
高影响因子
POLYMER DEGRADATION AND STABILITY
·
2024
·
IF 6.3
Kaixin Xu,Junli Xu,Panpan Hao,Ruiqi Zhang,Xiujie Cheng,Qing Zhou,Dongxia Yan,Yi Li,Jiayu Xin,Xingmei Lu
Recycling waste polyethylene terephthalate (PET) to prepare high-value chemicals can achieve resource recycling and reduce environmental pollution, which has important scientific significance. In this work, waterborne polyurethane (WPU) was prepared in one-pot method using non-metallic ionic liquid (IL) 1-ethyl-3-methylimidazolium acetate ( [Emim] [OAc]) as catalyst in the PET degradation. There is no need to separate the products and IL catalyst, avoiding product loss and metal residue. Meanwhile, the flame-retardant choline dihydrogen phosphate (N 1112OH DHP) was added, combining with the [Emim] [OAc], the WPU with good flame retardancy was obtained by using flame retardant with the phosphorus-nitrogen synergistic effect. The testing results indicated that the number average molecular weight (M n ) of WPU was as high as 23703 g/mol under the optimal conditions, the total heat release (THR) of WPU was reduced by 44.86%, the limiting oxygen index (LOI) was increased to 31.5%. Besides, the UL-94 testing of the WPU has reached V-0 level. In the end, the flame retardancy mechanism was studied through analyzing the perspectives of condensed phase and gas phase of of WPU. Thus, the WPU with good flame retardancy can be prepared in one-pot method by glycolysis of PET with ILs, which has certain guiding significance for the recycling and utilization of PET.
研究领域:
材料科学
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环境科学
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化学工程
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产品关联
DOI
高影响因子
CATALYSIS LETTERS
·
2021
·Vol. 152
·期 4
·1182-1193
·
IF 3.186
Shi Kaiyu,Guo Liying,Zheng Rongrong,Wang Haiyue,Chen Yanming
Five kinds of diacid comprising ionic liquid catalyst [HO 3 S–(CH 2 ) 4 -mim]Cl–MCl x ] were prepared, and their chemical structure, thermal stability and acidity were tested and analyzed. The performance evaluation of catalysts was carried out, and the process parameters were optimized. The cycling stability of the catalysts was investigated. Then, the catalytic degradation of polyethylene terephthalate (PET) was studied, and used mineral water bottles as an example. The chemical structure and molecular weight of the degradation product terephthalic acid bis(2-hydroxyethyl) ester (BHET) were analyzed. The results showed that among the catalysts synthesized, [HO 3 S–(CH 2 ) 4 -mim]Cl–FeCl 3 had the great catalytic performance and good thermal stability. According to the thermal gravimeter analysis, the decomposition temperature of the diacid ionic liquid catalyst ranges from 400 to 560 °C, while the degradation reaction temperatures in this paper are all below 250 °C, so that it has good thermal stability. At 190 °C, the PET alcoholysis rate reached 98.7% and the BHET yield reached 95.5% for 6 h, and the highest catalytic activity could still be maintained after 6 cycles, which indicate that the catalyst has excellent performance for degrading PET, and will have a great application prospect. Graphic Abstract
研究领域:
化学工程
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）