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The current commercial multistage reactor for methanol to propylene (MTP) process suffers from poor propylene selectivity and catalyst efficiency, mainly because of the low inlet methanol concentration and long residence time. In this work, we proposed an autothermal co‐current flow reactor for MTP process, where the reaction heat is continuously removed through heat exchange with cold reactants, thus single‐stage reactor can be used with higher methanol inlet concentration. The reactor feasibility was investigated by a three‐dimensional multiscale model, in which the diffusion–reaction interaction inside catalyst particle was described by a neural network model trained by machine learning. With the feeding methanol fraction increasing to 30%, propylene selectivity reaches 82.27% while the space velocity approaches 2.68 gMeOH gcat−1 h−1 at 99.97% methanol conversion, about 1.4 and 3.8 times those of a commercial multibed reactor, respectively. With proper catalyst bed dilution, the reaction temperature is well controlled between 700 and 754 K. [ABSTRACT FROM AUTHOR]

CO2 hydrogenation to CH3OH via heterogeneous catalysis is one of the most promising and available approaches for mitigation of anthropogenic CO2 issues. In this work, thermodynamic equilibria of CO2 to methanol were compared with experimental results at given conditions using a commercial Cu/ZnO/Al2O3 catalyst for CO hydrogenation to methanol. It was found that, the high pressure, low temperature, and high H2/CO2 ratio are favorable to methanol synthesis from CO2. Furthermore, the kinetic data were measured with an isothermal integral reactor under temperature between 160 and 240 °C, lower than that for CO hydrogenation to methanol reaction. Based on the single-active site and dual-active site LH mechanisms, both kinetic models can achieve full illustration of the influence of the operating conditions and the mechanisms. According to comparative analysis of the error variances of model correlations and the adsorbate coverages on the active sites, the dual-site mechanism identified to be superior to the single-site one for methanol synthesis from CO2 feedstock. Overall, this paper provides fundamental understanding of the thermodynamic and kinetic aspects of a central route for CO2 Valorisation. [ABSTRACT FROM AUTHOR]

Tumour‐associated macrophages (TAMs) abundantly infiltrate high‐grade gliomas and orchestrate immune response, but their diversity in isocitrate dehydrogenase (IDH)‐differential grade 4 gliomas remains largely unknown. This study aimed to dissect the transcriptional states, spatial distribution, and clinicopathological significance of distinct monocyte‐derived TAM (Mo‐TAM) and microglia‐derived TAM (Mg‐TAM) clusters across glioblastoma‐IDH‐wild type and astrocytoma‐IDH‐mutant‐grade 4 (Astro‐IDH‐mut‐G4). Single‐cell RNA sequencing was performed on four cases of human glioblastoma and three cases of Astro‐IDH‐mut‐G4. Cell clustering, single‐cell regulatory network inference, and gene set enrichment analysis were performed to characterize the functional states of myeloid clusters. The spatial distribution of TAM subsets was determined in human glioma tissues using multiplex immunostaining. The prognostic value of different TAM‐cluster specific gene sets was evaluated in the TCGA glioma cohort. Profiling and unbiased clustering of 24,227 myeloid cells from glioblastoma and Astro‐IDH‐mut‐G4 identified nine myeloid cell clusters including monocytes, six Mo/Mg‐TAM subsets, dendritic cells, and proliferative myeloid clusters. Different Mo/Mg‐TAM clusters manifest functional and transcriptional diversity controlled by specific regulons. Multiplex immunostaining of subset‐specific markers identified spatial enrichment of distinct TAM clusters at peri‐vascular/necrotic areas in tumour parenchyma or at the tumour–brain interface. Glioblastoma harboured a substantially higher number of monocytes and Mo‐TAM‐inflammatory clusters, whereas Astro‐IDH‐mut‐G4 had a higher proportion of TAM subsets mediating antigen presentation. Glioblastomas with a higher proportion of monocytes exhibited a mesenchymal signature, increased angiogenesis, and worse patient outcome. Our findings provide insight into myeloid cell diversity and its clinical relevance in IDH‐differential grade 4 gliomas, and may serve as a resource for immunotherapy development. © 2022 The Pathological Society of Great Britain and Ireland. [ABSTRACT FROM AUTHOR]