The massive consumption of petroleum and the increasingly deteriorating environment has triggered the attention and development of sustainable chemistry recently. Biomass source is the only renewable carbon source on Earth, which is regarded as the potential alternative to the current fossil fuels that cannot be regenerated in a short time. Past decades have witnessed great advances in the utilization of biomass with developed technologies. However, the quality of bio-oils obtained from pyrolysis at the various temperature is poor, which cannot be directly used as valuable chemicals and fuels. Molecular sieve catalyst (zeolite) have successfully applied in the catalytic conversion of different products after biomass pyrolysis, because of their uniform pore structure, strong acidity, and stable framework. This review emphasizes the traditional and the modification of the zeolite acidic active sites and pore structure and their roles in biomass catalytic pyrolysis. First, we compared the catalytic effects of biomass and its derivatives on traditional zeolites. The results show that ZSM-5 has the best catalytic effect (more high-value products), because of its shape selectivity. Different from the previous articles about the effect of modification on one side, this Review mainly introduces the combination of different methods to modify and optimize acidic sites and pores to improve the catalytic effect of rapid biomass pyrolysis. The zeolite was modified to improve the selectivity and yield of the target product, and a certain optimization effect was achieved. From different methods of mesopore formation to metal doping, the ways of adjusting zeolite catalysts and discussions of changes in acidity after metals being doped into zeolites are reviewed. Simultaneously, a hydrogen source was introduced to deal with the problem of insufficient hydrogen content, to improve the quality of bio-oils. Finally, the advantages and disadvantages of catalytic conversion over the modified zeolite (ZSM-5) are analyzed, and the prospects in this field are also discussed.

Compensation rules for patent infringement greatly affect patent quality, which is closely related to R & D investments. In this study, A duopoly game model was developed to analyze innovative factories’ R&D investment and patent licensing behavior, as well as the strategic choices of potential infringers under different compensation rules for patent infringement. Furthermore, a comparative analysis was conducted to analyze the patent quality under different scenarios, ultimately finalizing an optimal sequence rule for patent infringement compensation. The results show that patent quality is influenced by the invention height of patent and R&D efficiency, while the amount of patent infringement compensation has a great effect on potential infringement behavior. Patent quality can be effectively improved if the court adopts a proper sequence rule for patent infringement compensation according to the market circumstances.

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Fe/AC bifunctional catalysts provide an environmentally friendly strategy for the efficient catalytic conversion of low-density polyethylene into valuable fuel products.

Catalytic pyrolysis has been emerging as a promising strategy to tackle solid pollution induced by waste plastics, whereas achieving high selectivity of targeted products like valuable light aromatics remains a huge challenge. In this work, a novel protocol that combing waste plastic conversion and greenhouse gas CO 2 utilization was proposed for the first time. Different metal (Fe, Ni, Co, Mn, Ag, and Cu)-modified HZSM-5 zeolites were fabricated and then used as catalysts for the catalytic pyrolysis of low-density polyethylene (LDPE) with CO 2 as the reaction atmosphere. The introduction of CO 2 enhanced the selectivity of aromatic hydrocarbons from LDPE catalytic pyrolysis in comparison with a N 2 atmosphere, and a high liquid yield of more than 70% containing aromatic hydrocarbons, alkanes, and olefins was obtained with CO 2 catalytic conversion to CO over a nickel-modified HZSM-5 catalyst. In addition, the total selectivity of aromatics was 56.82% with that of benzene, toluene, ethylbenzene, and xylene (BTEX) being 43.63% at 550 °C. Compared with untreated HZSM-5, the metal-modified HZSM-5 catalyst also enhanced anticoking performance during catalytic reactions with the assistance of active CO 2 molecules. Besides, the involved catalytic reaction mechanism was also interpreted. The current work may offer a fresh route to the chemical recycling of waste plastics with simultaneous green CO 2 reutilization, advancing the development of catalytic conversion of hydrogen-rich solid waste into value-added products.

Fluid Catalytic cracking (FCC) unit is one of the means to lighten heavy oil in re neries, and its regenerated ue gas is also the main source of air pollutants from re nery. However, it is not clear about the type and amount of pollutants discharged from FCC units. The emissions of regenerated pollutants in the stack ue gases of three typical FCC units in China were investigated in this study, including a partial regeneration unit without a CO boiler (U1), a partial regeneration unit with a CO boiler (U2) and a full regeneration unit (U3). Different monitoring methods were used to analyze the concentration of sulfur dioxide (SO 2 ) and nitrogen oxides (NO x ), and the results showed that Fourier Transform Infrared Spectroscopy (FTIR) monitoring results of SO 2 and NO x are approximately 10 times and 5 times larger than that of the Continuous Emission Monitoring System (CEMS) data, respectively. Also, the contents of characteristic pollutants such as NH 3 , C 6 H 6 , HCN, C 8 H 8 , C 2 H 4 , CH 4 and CO were also monitored by FTIR, and the emission factors based on coke burn-off rate and throughput were investigated. The pollutants in U1 exhibited relatively higher contents with the NH 3 , HCN and C 6 H 6 of 116.99, 71.94 and 56.41 mg/Nm 3 in ue gas, respectively. The emission of regenerated pollutants in U2 and U3 are signi cantly different from U1. Regeneration processes (including coke properties, operating modes and presence or absence of CO boilers) affected pollutants emission factors in varying degree. At last, reasonable emission factors based on the different FCC regeneration processes contributes to the prediction, assessment and control for the pollutants emission.

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