Converting CO to olefins is an ideal route to achieve carbon neutrality. However, selective hydrogenation to light olefins, especially single-component olefin, while reducing CH formation remains a great challenge. Herein, we developed ZnZrO /SSZ-13 tandem catalyst for the highly selective hydrogenation of CO to light olefins. This catalyst shows C -C and propylene selectivity up to 89.4 % and 52 %, respectively, while CH is suppressed down to 2 %, and there is no obvious deactivation. It is demonstrated that the isolated moderate Brønsted acid sites (BAS) of SSZ-13 promotes the rapid conversion of intermediate species derived from ZnZrO , thereby enhancing the kinetic coupling of the reactions and inhibit the formation of alkanes and improve the light olefins selectivity. Besides, the weaker BAS of SSZ-13 promote the conversion of intermediates into aromatics with 4-6 methyl groups, which is conducive to the aromatics cycle. Accordingly, more propene can be obtained by elevating the Si/Al ratio of SSZ-13. This provides an efficient strategy for CO hydrogenation to light olefins with high selectivity.
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http://dx.doi.org/10.1002/anie.202316874 | DOI Listing |
Org Biomol Chem
January 2025
Henan Key Laboratory of Chemical Biology and Organic Chemistry, Key Laboratory of Applied Chemistry of Henan Universities, Green Catalysis Center, and College of Chemistry, Zhengzhou University, Zhengzhou 450052, China.
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View Article and Find Full Text PDFPhotosynth Res
January 2025
Research Institute for Interdisciplinary Science and Graduate School of Natural Science and Technology, Okayama University, Okayama, 700-8530, Japan.
Red algae are photosynthetic eukaryotes whose light-harvesting complexes (LHCs) associate with photosystem I (PSI). In this study, we examined characteristics of PSI-LHCI, PSI, and LHCI isolated from the red alga Galdieria sulphuraria NIES-3638. The PSI-LHCI supercomplexes were purified using anion-exchange chromatography followed by hydrophobic-interaction chromatography, and finally by trehalose density gradient centrifugation.
View Article and Find Full Text PDFPhotosynth Res
January 2025
Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Leninskie Gory, Moscow, Russia, 119991.
The femtosecond dynamics of energy transfer from light-excited spirilloxanthin (Spx) to bacteriochlorophyll (BChl) a in the reaction centers (RCs) of purple photosynthetic bacteria Rhodospirillum rubrum was studied. According to crio-electron microscopy data, Spx is located near accessory BChl a in the B-branch of cofactors. Spx was excited by 25 fs laser pulses at 490 nm, and difference absorption spectra were recorded in the range 500-700 nm.
View Article and Find Full Text PDFCurr Top Dev Biol
January 2025
Department of Pharmacology, School of Medicine, Case Western Reserve University, Cleveland, OH, United States. Electronic address:
Animals perceiving light through visual pigments have evolved pathways for absorbing, transporting, and metabolizing the precursors essential for synthesis of their retinylidene chromophores. Over the past decades, our understanding of this metabolism has grown significantly. Through genetic manipulation, researchers gained insights into the metabolic complexity of the pathways mediating the flow of chromophore precursors throughout the body, and their enrichment within the eyes.
View Article and Find Full Text PDFACS Cent Sci
January 2025
Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy, School of Pharmacy, Xuzhou Medical University, 209 Tongshan Road, Xuzhou 221004, China.
Herein, we report a visible-light-induced charge-transfer-complex-enabled dicarboxylation and deuterocarboxylation of C=C bonds with oxalate as a masked CO source under catalyst-free conditions. In this reaction, we disclosed the first example that the tetrabutylammonium oxalate could be able to aggregate with aryl substrates via π-cation interactions to form the charge transfer complexes, which subsequently triggers the single electron transfer from the oxalic dianion to the ammonium countercation under irradiation of 450 nm bule LEDs, releasing CO and CO radical anions. Diverse alkenes, dienes, trienes, and indoles, including challenging trisubstituted olefins, underwent dicarboxylation and anti-Markovnikov deuterocarboxylation with high selectivity to access valuable 1,2- and 1,4-dicarboxylic acids as well as indoline-derived diacids and β-deuterocarboxylic acids under mild conditions.
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