Walnut shell oil-bath torrefaction coupled with fast pyrolysis: Effect of torrefaction heating modes.

Lignocellulosic biomass, renewable with short growth cycle and diverse sources, can be substituted fossil fuel. However, low effective hydrogen-to-carbon ratio (H/Ceff) limits its applications. Torrefaction and co-pyrolysis with high H/Ceff feedstocks are promising technology. This paper investigated the effect of heating modes on oil-bath torrefaction of walnut shells, followed by fast co-pyrolysis. Six heating modes during oil-bath torrefaction were evaluated. Com1 (Microwave 67 %, Lightwave 33 %) yielded the lowest residual yield 84 wt%, while the highest gas production 495.47 mL/g which mainly composed of CO and CO2. Torrefied feedstock under Com1 had the highest H/Ceff. Decarboxylation and decarbonylation reactions dominated among oil-bath torrefaction. Com1 produced the most hydrocarbons and least oxygen-containing compounds. As microwave ratio decreased, the content of olefins, acids and phenols decreased, monocyclic aromatic hydrocarbons and alcohols was showed opposite tend. This study offers new ideas for microwave and lightwave torrefaction and promoting hydrocarbon production from lignocellulosic biomass.

ZSM-5@ceramic foam composite catalyst derived from spent bleaching clay for continuous pyrolysis of waste oil to produce monocyclic aromatic hydrocarbons.

Spent bleaching clay, a solid waste generated during the refining process of vegetable oils, lacks an efficient treatment solution. In this study, spent bleaching clay was innovatively employed to fabricate ceramic foams. The thermal stability analysis, microstructure, and crystal phase composition of the ceramic foams were characterized by TG-DSC, SEM, and XRD. An investigation into the influence of Al2O3 content on the ceramic foams was conducted. Results showed that, as the Al2O3 content increased from 15 wt% to 30 wt%, there was a noticeable decrease in bulk density and linear shrinkage, accompanied by an increase in compressive strength. Additionally, the ceramic foams were used as catalyst supports, to synthesize ZSM-5@ceramic foam composite catalysts for pyrolysis of waste oil. The open pores of the ZSCF catalyst not only reduced diffusion path length but also facilitated the exposure of more acid sites, thereby increasing the utilization efficiency of ZSM-5 zeolite. This, in turn, engendered a significant enhancement in monocyclic aromatic hydrocarbons content from 39.15 % (ZSM-5 powder catalyst) to 78.96 %. Besides, a larger support pore size and a thicker ZSM-5 zeolite coating layer led to an increase in monocyclic aromatic hydrocarbons content. As the time on stream was extended to 56 min, the monocyclic aromatic hydrocarbon content obtained with the composite catalyst remained 12.41 % higher than that of the ZSM-5 powder catalyst. These findings validate the potential of the composite catalyst. In essence, this study advances the utilization of spent bleaching clay and introduces a novel concept for ceramic foam fabrication. Furthermore, it contributes to the scaling up of catalytic pyrolysis technology.

Research progress on pyrolysis of nitrogen-containing biomass for fuels, materials, and chemicals production.

Pyrolysis of nitrogen-containing biomass holds tremendous potential for producing varieties of high value-added products, alleviating energy depletion. Based on the research status about nitrogen-containing biomass pyrolysis, the effect of biomass feedstock composition on pyrolysis products is first introduced from the aspects of elemental analysis, proximate analysis, and biochemical composition. The properties of biomass with high and low nitrogen used in pyrolysis are briefly summarized. Then, with the pyrolysis of nitrogen-containing biomass as the core, biofuel characteristics, nitrogen migration during pyrolysis, the application prospects, unique advantages of nitrogen-doped carbon materials for catalysis, adsorption and energy storage are introduced, as well as their feasibility in producing nitrogen-containing chemicals (acetonitrile and nitrogen heterocyclic) are reviewed. The future outlook for the application of the pyrolysis of nitrogen-containing biomass, specifically, how to realize the denitrification and upgrading of bio-oil, performance improvement of nitrogen-doped carbon materials, as well as separation and purification of nitrogen-containing chemicals, are addressed.

Co-torrefaction of corncob and waste cooking oil coupled with fast co-pyrolysis for bio-oil production.

Lignocellulosic biomass is a rich source of fixed renewable carbon and a promising alternative to fossil sources. However, low effective hydrogen to carbon ratio limits its applications. This work studied the influence of oil-bath co-torrefaction of corncob and waste cooking oil for co-pyrolysis. It was compared with dry torrefaction and hydrothermal wet torrefaction firstly. Residual of oil-bath co-torrefaction were the highest of 97.01 %. Oil-bath co-torrefaction could maximize hydrogen atoms retention in corncob, which has a positive significance for deoxygenation during pyrolysis. Oil-bath co-torrefaction could also reduce the average activation energy required for corncob decomposition, while it was increased with dry torrefaction. Oil-bath co-torrefaction coupled with co-pyrolysis was more suitable for hydrocarbon-rich bio-oil production. Oil-bath co-torrefaction temperature had the greatest influence on bio-oil composition. High pressure promoted formation of the CC double bond and degradation of lignin, which further promoted the formation of monocyclic aromatics in bio-oil.

[The working principle and prototype construction of the Chinese vestibular prosthesis].

Objective:To complete the working principle design and prototype construction of the Chinese multichannel vestibular prosthesis （CMVP） with independent intellectual property rights, and verify its working performance, so as to lay the foundation for the clinical promotion and application of CMVP. Methods:On the basis of previous research, the working principle of CMVP was constructed based on the information encoding principle of vestibular nervous system, and the circuit was designed according to the principle. Then, appropriate electronic components and software systems were selected to construct a CMVP prototype according to the design. Finally, the input and output characteristics of the CMVP prototype were verified through the performance test. Results:In the present study, a block diagram of the working principle of the CMVP was successfully designed and drawn, and the working principle was explained in detail according to the block diagram. Further, the circuit diagram of the CMVP was designed and drawn based on the working principle, then the selected electronic components and software systems were combined one by one to complete the construction of a prototype. Finally, the performance test for the prototype was completed, which showed that all stimulus electrodes of the prototype could output biphasic pulse current, and the frequency of biphasic pulse current was modulated by the spatial rotation data input sensed by a motion sensor. Conclusion:The working principle and circuit design of the CMVP are reasonable; the CMVP prototype in China has been successfully constructed; the spatial rotation motion sensing input and the modulated pulse current output are stable and reliable.