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Copyright of Journal of Shenyang Agricultural University is the property of Journal of Shenyang Agricultural University Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Biomass, as a renewable energy source, features wide availability, multiple functions, and carbon neutralization. The high-value resource utilization of biomass is conducive to reducing reliance on high-carbon fossil energy, ensuring national energy security, and curbing environmental pollution, aligning with the needs of China's "dual carbon" national strategy. Pyrolysis, as the foundation of biomass thermochemical conversion, is one of the best technologies to achieve a high-value utilization of biomass energy. However, it has some core issues such as low bio-oil yield and poor quality. To overcome these problems, a cryogenic technology was innovatively applied to the field of biomass pyrolysis, and a new biomass oil production method of "cryogenic + fast pyrolysis" was proposed to increase the yield and quality of pyrolytic bio-oil. Taking two types of crop straw as experimental research objects, the rapid freezing pretreatment method with liquid nitrogen was adopted to study the evolution mechanism of the product distribution and composition of biomass pyrolysis under cryogenic pretreatment. The experiments show that compared with conventional pyrolysis, the increase in the bio-oil yield after cryogenic pretreatment of biomass pyrolysis can reach 14.16% to 23.73%, and the cryogenic pretreatment temperature has a positive correlation with the bio-oil yield, and the maximum bio-oil yield (22.3% to 26.3%) is reached at −90 ℃, exceeding the bio-oil yield of the aluminum method by 8.50% to 22.71%. The cryogenic pretreatment has a significant transformation effect on the composition of the bio-oil, and the content of benzene series (BTEX) and phenolic substances in the bio-oil composition increases significantly, with the maximum increase of 43.61% and 12.45%, respectively. The cryogenic pretreatment of liquid nitrogen inhibited the release of CO2 and CO in biomass pyrolysis gas, and the proportion of components decreased by 7.2%−29.7%. In addition, the inhibition of the release of CO2 and CO in the biomass pyrolysis gas and the increase of CH4 and H2 by cryogenic pretreatment increase by 0.2% to 14.7%. Moreover, the increase in C content and the decrease in O content in the solid product under cryogenic pretreatment are conducive to improving the combustibility of biochar and reducing its risk of spontaneous combustion.

Copyright of Journal of Xinjiang University (Natural Science Edition) is the property of Xinjiang University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The polymer precursor derived ceramics route is one of the important ways for the preparation of ceramics, and pyrolysis is absolutely necessary in the process. The traditional thermal pyrolysis suffers from slow heating/cooling rate, long processing time, and high energy consumption. In recent years, new technologies, including laser pyrolysis, microwave treatment, and discharge plasma sintering, have attracted the attention in the researchers due to the advantages of fast heating/cooling rate and low energy consumption. This paper summarizes the research progress in rapid pyrolysis in PDCs. The advantages of the new technologies in the preparation of high-performance ceramics are also discussed. [ABSTRACT FROM AUTHOR]

Copyright of Chemistry & Industry of Forest Products is the property of Chemistry & Industry of Forest Products Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The total production of global plastics is up to 400 million tons per year. Nearly 80% of the used plastics are directly landfilled or dumped in the environment, leading to the generation and release of microplastics, which poses a great threat to both environment and human health. How to recycle plastic waste efficiently and environmentally has become a common concern worldwide. Among the plastic waste recycling methods, chemical recycling such as pyrolysis can realize the transformation from polymer to high-value products. This paper summarizes the research and industrialization progress of four different plastic waste pyrolysis technologies, namely fast pyrolysis, catalytic pyrolysis, oxidative pyrolysis and hydro-pyrolysis. The challenges faced by the pyrolysis of plastic waste is discussed and the future development direction of various pyrolysis technologies is also outlooked. It is expected that some more efficient, environmentally friendly, and economical technologies of plastic waste pyrolysis can be explored in the future, to meet the growing demand for environmental protection and sustainable development.

The effect of alkali/alkaline earth metals (AAEM) on biomass pyrolysis and the composition of pyrolysis products can provide important theoretical basis for the study of biomass pyrolysis characteristics and the efficient utilization of pyrolysis products. In this paper, pine sawdust was used as pyrolysis raw materials, and the acid washed sample was soaked with potassium, calcium, sodium and magnesium chloride solution, respectively. The samples were rapidly pyrolyzed at 500℃under Ar atmosphere. The influence of four metal ions on the composition and distribution of pine sawdust pyrolysis products was investigated. The pyrolysis characteristics of each sample were investigated by thermo-gravimetric analysis. The tar components of the fast pyrolysis were investigated by gas chromatography/mass spectrometry (GC/MS). The results show that: AAEM has obvious catalytic effect on pine sawdust, the existence of AAEM ions can improve the yield of pyrolysis gas and solid, reduce the yield of tar; AAEM can reduce the pyrolysis temperature and make the pyrolysis easier; the tar components of fast pyrolysis mainly include phenols, ketones, aldehydes, aromatics, alcohols, dehydrated sugars, furans, acids and AAEM will cause changes in the relative contents of these substances, especially furans and aromatics. These experimental results provide an important reference for optimizing the pyrolysis conditions of biomass and improving the quality of pyrolysis bio-oil. [ABSTRACT FROM AUTHOR]

The thermogravimetric analysis method was used to research the pyrolysis characteristics of chitin with KOH, and the effect of different impregnation ratios on the pyrolysis process was analyzed. The pyrolysis kinetic parameters were obtained by using the Coats-Redfern integral theory. The effect of KOH on the activation energy of the main pyrolysis process of chitin was investigated. The results of thermogravimetric showed that the addition of KOH changed the pyrolysis behavior of chitin, reduced the activation energy of pyrolysis accelerated the reaction rate and promoted the pyrolysis of chitin. Chitin could be fast pyrolysis with KOH at 140°C and m (65% KOH) : m ( chitin) = 2:1 or 3 : 1. The calculating results of pyrolysis kinetic parameters indicated that chitin pyrolysis with KOH was a complex reaction. [ABSTRACT FROM AUTHOR]

Copyright of Advances in New & Renewable Energy is the property of Editorial Office of Advances in New & Renewable Energy and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to develop cheap and high-efficiency activated chars for desulfuration, bituminous coal powders were used to prepare activated chars through fast pyrolysis process in a drop-tube reactor and the effect of oxygen concentration on pore structure was investigated. The samples were characterized by QSDFT (quenched solid density functional theory) method using nitrogen adsorption and scanning electronic microscopy (SEM).The results indicate that devolatilization is a dominate process during the pyrolysis of coal powders at low oxygen levels. The absorption isotherms of char samples show some features of type I and type IV isotherms, characterized with a significant proportion of micropore structure. Surface ablation was studied from a microscopic view and it shows that the shape of surface ablation is nearly circular. Meanwhile, with the increase of oxygen concentration, the surface ablation develops from the surface to the interior of particle. Moreover, the results show that appropriate oxygen concentration is beneficial to the development of pore structure. When the oxygen concentration is below 6%,the pore volume and surface area increase with the increase of oxygen concentration, while when the oxygen concentration increases to a certain degree (i. e.,> 8%), the pore volume and the surface area are obviously reduced due to the collapse of pore structure. [ABSTRACT FROM AUTHOR]

Shenmu bituminous coal was pyrolyzed and then gasified in a 10 t/h circulating fluidized bed of coal fast pyrolysis system to investigate the operation characteristics, coal pyrolysis characteristics and product distribution in the fluidized bed pyrolysis reactor. The results show that the contents of H2 and CH4 is high in pyrolysis gas with the low heat value of about 11~15 MJ/m³. The tar distillation range analysis demonstrate that light fraction content is about 47.00%. Proximate analysis of semi-coke clearly displays that the content of fixed carbon content is high and that of volatile is low. [ABSTRACT FROM AUTHOR]