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In this work, the Zr-Mg bimetallic catalyst is prepared and used to facilitate the conversion of the waste mask to hydrocarbon-rich fuels. The effects of the catalyst and the reaction atmosphere on pyrolysis behaviors of different layers of the mask are discussed, and the interactions between CO 2 and the catalyst are analyzed. The results showed that the synthesized catalyst significantly promoted the conversion of long-chain hydrocarbons to short-chain hydrocarbons. Compared with pyrolysis alone under N 2 atmosphere, the relative contents of hydrocarbon compounds obtained by catalytic pyrolysis in the inner layer and middle layer increased by 12.21% and 16.24%, respectively. Additionally, the relative content of olefins in the liquid product increased by 9.62%. When the pyrolysis atmosphere was changed from N 2 to CO 2 , the selectivity of the cycloalkanes was significantly enhanced. Also, the interactions between CO 2 and the catalyst improved the selectivity of C 2 H 6. These works provide important support for the effective disposal of masks and an in-depth understanding of the CO 2 -assisted pyrolysis process. • A catalyst that promotes the generation of hydrocarbon-rich fuels is synthesized. • The selectivity of short-chained liquid hydrocarbons is increased by 13.87%. • The CO 2 promotes the generation of C 3 H 6 in gaseous hydrocarbon products. • Effects of CO 2 and catalyst converting mask into hydrocarbon-rich fuels are given. [ABSTRACT FROM AUTHOR]

In our work, a series of experiments on pyrolysis of the large particle oil shale (6–15 mm) were carried out in a self-made retorting pyrolyzer, in order to obtain the optimal final pyrolysis temperature of Huadian oil shale and evaluate the catalytic performance of transition metal salts (CoCl 2 ·6H 2 O, MnSO 4 ·H 2 O) in promoting the shale oil yield and product characteristic. The experiment results showed that the retorting temperature significantly influenced the shale oil yield. The maximum oil yield appeared in 520 °C with the result of 21.59 wt%. Meanwhile, the higher retorting temperature promoted the more production of alkanes/olefins, which led to the increase of alkanes from 20.46% to 32.44%. Moreover, the use of CoCl 2 ·6H 2 O salt further increased the oil yield. The pyrolysis behavior and kinetic analysis indicated the transition metal iron could act as the activation center to accelerate the breakdown of chemical bonds in organic matters. In addition, the addition of the Co salt significantly enhanced the formation of aromatic hydrocarbons in the shale oil, which increased about 18% compared to that of non-catalytic pyrolysis. It had demonstrated the Co iron could increase the selectivity of aromatic hydrocarbons and promote olefin aromatization. The acid compounds were observed in the oil produced from the catalytic pyrolysis of MnSO 4 ·H 2 O, which suggested that it was not suitable to be regarded as the candidate catalysis. [ABSTRACT FROM AUTHOR]

In this work, the effects of formate salts(potassium/nickel/zinc formate) on behavior, yield, and product characteristics were evaluated and compared by using the combination of TGA and the fixed-bed reactor. The results showed that potassium formate had a good catalytic cracking ability , resulting in a forward shift of the decomposition temperature of organic components in biomass and an increase of gas yield. The nickel formate had the strongest catalytic ability for biomass pyrolysis to produce oil. Compared to the non-catalytic pyrolysis, the yield of bio-oil increased about 8 wt%. After adding potassium formate, the generation of phenols in the oil was enhanced, while the presence of nickel/zinc formate obtained the opposite results. The total content of oxygenated compounds(alcohols, ketones, esters and acids) was reduced for all formate salts, and the most signigicant difference among them was that the addition of potassium formate obtained the enrichment of ketones. Moreover, the analysis of gas showed that the yields of CO 2 and CO were increased after adding potassium/nickel formate. The reasons were related to the differences in physicochemical property of catalyst and catalytic ability of metal cation in formate salt. • A comparative study on formate-assisted pyrolysis of CS is performed. • Enhancement of selectivity toward ketones is found by adding potassium formate. • More CO 2 and CO are generated by adding potassium formate and nickel formate. • Effect of potassium formate is most significant among the used formate salts. [ABSTRACT FROM AUTHOR]

The extraction of phenolic compounds from biomass is an important way to replace chemical synthesis techniques, and catalytic pyrolysis of biomass is an effective method to obtain phenolic compounds with high selectivity. In this work, cobalt-modified montmorillonite K-10(CMT) catalyst was prepared by using cobalt salt and montmorillonite K-10(MMT), and used to catalyze the pyrolysis of corn stalk(CS) to produce phenol-rich bio-oil. The catalytic pyrolysis characteristics reflected by the liquid and gaseous components were compared using gas chromatography-mass spectrometry(GC-MS) and online mass spectrometry(online MS), and the catalytic pyrolysis behavior of corn stalk was analyzed by using the thermogravimetric analyzer(TGA). The addition of catalyst resulted in the increase of apparent activation energy of pyrolysis process but increased selectivity for phenolic compounds. Compared with the blank sample, the relative content of phenolic compounds in bio-oil increased by 11.99 %, and the selectivity of alkyl-phenols was stronger. In addition, the results also showed that the synthesized catalyst promoted the production of H 2 and CH 4 during the catalytic pyrolysis. The optimum ratio of the prepared catalyst was 6%Co/15%MMT. These works provide an alternative approach to upgrading bio-oil product. • A catalyst that effectively improves the selectivity of phenols is synthesized. • A 11.99 % increase in phenols is obtained by adding 6%Co/15%MMT catalyst. • The reforming of oxygenates to form phenolic compounds is enhanced. • A pathway for producing phenols via biomass catalytic pyrolysis is presented. [ABSTRACT FROM AUTHOR]

• The pyrolysis characteristics of thermal bitumen in semi-coke and extracted bitumen were analyzed and compared. • The extracting solvents (a mixture of ionic liquid [Bmim]Cl and NMP) were rarely used in the oil shale extraction. • Gaussian fitting method was used to evaluate the proportions of bond cleavages and their kinetic parameters. Fushun oil shale semi-coke and its extracted bitumen were prepared for analyzing their pyrolysis characteristics by TG–DTG, TG–FTIR, and Py–GC/MS. Semi-coke was the residue of oil shale pyrolyzed to 450 °C, and extracted bitumen was the organic matter extracted from semi-coke with [Bmim]Cl/NMP mixed solvents. Gaussian fitting method was used to analyze the proportions of bond cleavage reactions occured during the pyrolysis to 700 °C at a heating rate of 20 °C/min. Results showed that 3–4 kinds of bond cleavages were mainly involved. The outstanding pyrolysis behaviors were contributed by the cleavages of C al C al and weak bonds (including volatilization). The kinetic parameters based on Coats–Redfern method were calculated from the points for each pyrolysis stage and bond cleavage reaction. The evolution processes of typical gaseous products and distributions of flash pyrolysis products were displayed in detail, exhibiting the prominent roles of aliphatic compounds, CH 4 , and CO 2. Moreover, the releases of the typical gaseous products for semi-coke tended to occur at higher temperatures. [ABSTRACT FROM AUTHOR]