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Co-process of biomass and coal is perceived as a way to enhance the energy utilization by virtue of the integrated and interactive effects between different types of carbonaceous fuels. The purpose of this study was to investigate the co-pyrolysis characteristics of Yining coal and poplar sawdust, and to determine whether there is any synergistic effect in pyrolytic product yields. The coal was blended with sawdust at a mass fraction of 9:1, 7:3, 5:5, 3:7 and 1:9 respectively. The change of char yields, maximum weight loss rate and the corresponding temperature of different coal/sawdust blends during pyrolysis were compared by thermogravimetric analysis (TG). The total tar yields during separate coal, sawdust as well as their blends pyrolysis were acquired from the low temperature aluminum retort distillation test. By compare the experimental and theoretical value of the char yields from TG and tar yields from carbonization test, it was observed that co-pyrolysis of coal/sawdust blends produced less char and tar than the total amount produced by separate coal and sawdust pyrolysis. The different product distribution suggested that there was synergy effect in gas product yields. The co-pyrolysis of demineralized and devolatilized sawdust with coal indicated that the ash in the sawdust was the main contributor to the synergistic effect.

A Na-based fluxing agent Na2O (NBFA) and a composite fluxing agent (mixture of CaO and Fe2O3 with mass ratio of 3:1, CFA for short) were used to decrease the ash fusion temperature of the Dongshan and Xishan coal from Shanxi of China and make these coal meet the requirements of the specific gasification process. The main constituents of the fluxing agents used in this study can play a catalyst role in coal gasification. So it is necessary to understand the effect of fluxing agents on coal gasification reactivity and gas composition. The results showed that the ash fusion temperature of the two coal used decreased to the lowest point due to the eutectic phenomenon when 5 wt% of CFA or NBFA was added. Simultaneously, the gas molar ratio of H2/CO changed when CFA was added. A key application was thus found where the gas molar ratio of H2/CO can be adjusted by controlling the fluxing agent amount to meet the synthetic requirements for different chemical products.

It is significant for saving energy to manufacture superb‐property batteries. Carbon is one of the most competitive anode materials in batteries, but it is hard for commercial graphite anodes to meet the increasingly higher energy‐storage requirements. Moreover, the price of other better‐performing carbon materials (such as graphene) is much higher than graphite, which is not conducive to massive production. Pitch, the cheap by‐product in the petroleum and coal industries, has high carbon content and yield, making it possible for commercialization. Developing pitch‐based anodes can not only lower raw material costs but also realize the pitch′s high value‐added utilization. We comprehensively reviewed the latest synthesis strategies of pitch‐derived materials and then introduced their application and research progress in lithium, sodium, and potassium ion batteries (LIBs, SIBs, and PIBs). Finally, we summarize and suggest the pitch′s development trend for anodes and in other fields. [ABSTRACT FROM AUTHOR]

Highlights: [•] CO2 atmosphere is favorable to the release of H2O during coal pyrolysis. [•] Initial evolution temperature of gas shows a notable dependency on atmosphere and pressure. [•] Chars prepared in CO2 atmosphere have more cycloalkane and aliphatic structures. [•] CO2 atmosphere is beneficial to the growth of char crystal layer in vertical position. [Copyright &y& Elsevier]

Highlights: [•] CO2 utilization as gasifying agent during H2O-char gasification was studied. [•] Synergy was revealed during coal gasification with CO2/H2O mixture in low temperature. [•] The high catalytic activity of Ca species in CO2 gasification leads to the synergy. [ABSTRACT FROM AUTHOR]