The ever-increasing amount of anthropogenic carbon dioxide (CO2) emissions has resulted in great environmental impacts, the heterogeneous catalysis of CO2 hydrogenation to methanol is of great significance.

With the gradual diminishing of fossil fuel reserves and growing concerns about global warming as a result of the over-dependence on fossil-based resources, finding ways of exploiting feasible pathways for the replacement of fossil-based chemicals is highly desirable.[1] To meet this growing demand, biomass and CO 2 have been regarded as "carbon-neutral" resources to produce sustainable chemicals, fuels, and materials, and these substances have garnered much attention in recent years.[2]Lignocellulosic biomass is of particular interest because such materials are the most-abundant carbon resources on the planet, and they primarily consist of a complex mixture of lignin ( % 15-30 %), hemicellulose ( % 25-30 %), and cellulose (%35-50 %).[3] The integrated pretreatment and enzymatic hydrolysis process for the conversion of cellulose and hemicellulose found in lignocellulose into monosugars for bioenergy and biochemical production through biological pathways is a recognized strategy in modern biorefinery, and lignin is produced as a byproduct of this process.[4] With the aim of establishing a cost-competitive lignocellulose-based bioeconomy, the use of every penny and the exploitation of value-added applications of the main components in lignocellulose, such as lignin, are still in high demand. [5] In our previous study, with the cheap ionic liquid dissolution pretreatment of corn stover, around 60 wt % of lignin (IEL) was extracted, and the regenerated sample presented high enzymatic hydrolytic efficiency with full conversion of carbohydrates into monosugars in less than 24 h; this process is accompanied by the production of a new enzymatic hydrolytic lignin

A Schiff base-modified silver catalyst was developed for the direct carboxylation of terminal alkynes with CO2, enabling the efficient synthesis of valuable alkynyl carboxylic acids.

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How to enhance heavy oil recovery to meet the oil consumption is a popular issue around the world, and it has attracted widespread attention. A two-dimensional visualized model was adopted to study the pore-scale mechanisms and development effects of foam for enhancing oil recovery in steam injection processes for heavy oil. Experimental images visually presented that small bubbles gather together to form bigger foams, thus blocking the small pores and throats and leading to fluid diversion in porous media. As a result, the sweep efficiency was improved from 46.18% to 77.93% after foam injection. Foams could effectively improve the mobility ratio between oil and water and decreased water cut after foam injection, which was significant for decaying the decline of oil production. As for the pore-scale level, after foams were injected into the visualized model, the residual oil caused by steam flooding entered into the main streamline under the disturbance of foams and was carried out by the following displacement fluid. The heavy oil was emulsified into O/W emulsions that had lower viscosity under the action of foams; hence, more trapped oil was mobilized and displaced. As a result, the micro oil displacement efficiency increased from 72.76% to 84.01%. In order to provide a reference for the choice of foam injection, experiments that investigated development effects of cold foam and hot foam were also conducted. Compared with the incremental of oil recovery caused by cold foam, that induced by hot foam was 41.51% higher, demonstrating that the coinjection of steam and foam was more advantageous to heavy oil production.

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Flue gas mainly consists of N2 and CO2 and is applied in petroleum industry as a kind of displacement agents. In this paper, flue gas was introduced into the thermal recovery process of thick heavy oil reservoir. First, the PVT experiments under different conditions were carried out to research the dissolution of flue gas in crude oil. Then, a series of 3D physical simulations were performed to study the oil displacement characteristics of flue gas coupled with steam flooding in a thick reservoir with consideration of the important production parameters including oil production, oil-to-steam ratio (OSR), water cut, and oil recovery in both the steam-flooding process and the process of steam flooding coupled with flue gas. Finally, the enhanced oil recovery mechanisms of flue gas coupled with steam flooding for thick heavy oil reservoirs were summarized on the basis of the experimental results. This study provided a reference that the reasonable use of flue gas can improve recovery of thick heavy oil reservoirs while reducing greenhouse gas emissions.