Huakai Li, Zhiquan Yu*, Zhixin Zhang, Shushuang Li, Zhen Shi, Changjun Ni, Lei Cao, Hong Du, Qun-Xing Luo*, Feng Wang
Industrial & Engineering Chemistry Research, 2024, DOI: 10.1021/acs.iecr.4c00388
A series of SiO2-supported silicotungstic acid (STA/SiO2) catalysts were prepared by the incipient impregnation method and utilized in dehydration of ethanol to ethylene. The catalysts were characterized through XRD, N2 physical adsorption, TEM, XRF, FTIR, Py-FTIR, Raman spectroscopy, and TG/DSC. The influence of loading amount and calcination temperature on the properties and catalytic activities were investigated. The yield of ethylene was 93.9% at an ethanol conversion of 96.9% over the 36-STA/SiO2(250) catalyst at 240 °C and 1.0 MPa. The kinetics study indicated that diethyl ether was an intermediate under the investigated reaction conditions. A consecutive slow decrease in ethanol conversion and ethylene yield was observed after the 800-h run, which was due to the decreased Brønsted amount caused by carbon deposition, rather than the change of crystal phase or leaching of active sites.
Shiyang Liu, Yike Huang, Nengchao Luo*, Jian Zhang, Botao Qiao, Feng Wang*
ACS Catalysis, 2024, DOI: 10.1021/acscatal.4c01132
Dimethyl ether (DME) coupling via prior C−H bond scission affords H2 and long-chain oxygenates that can be used as diesel fuel additives. However, the C−H bond of DME is recalcitrant, requiring oxidants to activate for subsequent C−C bond coupling, whereas over-oxidation to CO2 by non-selective oxidants is inevitable. Here, by establishing a channel for hole transfer from Pt/TiO2 photocatalyst to DME, the C−H bond of DME is broken, affording H2 and diesel fuel additives consisting of glycol dimethyl ether (GDE) and the oligomers. Adsorbed water on Pt/TiO2 fosters the hole transfer by forming hydrogen bonds with both Pt/TiO2 surface and DME. Because of the hydrogen bonding, photogenerated holes are extracted from Pt/TiO2 by water and eventually transferred to DME. Therefore, the productivities of the diesel fuel and H2 are improved to 8.7 and 12.4 folds. This work provides a route to produce two kinds of fuels from abundant feedstock.
Yinpan Zhang, Qiang Guo*, Feng Wang*
ChemCatChem, 2024, DOI: 10.1002/cctc.202301568
The carbonylation reaction of olefins is one of the significant pathways for the synthesis of oxygen-containing compounds such as aldehydes, esters, and amides. The ethylene carbonylation reactions have drawn much interest since they produce important chemicals such as propionaldehyde and methyl propionate, which are crucial intermediates for the synthesis of polymers. Moreover, ethylene carbonylation, coupled with C-C bond formation, shows great promise for the synthesis of 3-pentanone. However, due to the presence of various competing reactions, balancing the activity and selectivity of ethylene carbonylation reactions has remained a challenge. This concept article aims at describing the recent advances in the ethylene carbonylation with different hydrogen sources.
Lulu Sun, Nengchao Luo*
J. Energy Chem., 2024, 94, 102-127, DOI:10.1016/j.jechem.2024.02.053
Lignocellulosic biomass is the largest renewable hydrocarbon resource on earth. Converting cellulose, one of the major components of lignocellulose, powered by solar energy is a promising way of providing low-carbon-footprint energy chemicals such as H2, HCOOH, CO, and transportation fuels. Charge separation in photocatalysts and interfacial charge transfer between photocatalysts and cellulose affect the activity and selectivity of cellulose refineries to H2 and carbonaceous chemicals. This review summarizes photocatalysts for the refineries of cellulose and downstream platform molecules based on the types of products, with the structure features of different types of photocatalysts discussed about the targets of either improving the activity or product selectivity. In addition, this review also sheds light on the methods for designing and regulating photocatalyst structures, meanwhile summarizing proposed future research challenges and opportunities.
Zhuyan Gao#, Puning Ren#, Lulu Sun, Nengchao Luo*, and Feng Wang*
Nature Synthesis, 2024, DOI: 10.1038/s44160-024-00499-4
Photocatalysis has emerged as a green protocol for biorefineries thanks to sustainable energy input. The unique radical mechanism of photocatalysis allows the decomposition of raw biomass and the precise functionalization of platform molecules, but radicals with open-shell electronic structures are highly active, resulting in diverse products. Control of the radical mechanism relies on photocatalysts guiding interfacial charge transfer for chemical bond breaking. The reaction behaviour of radicals and the surface states of semiconductor photocatalysts are therefore crucial for controlling the efficiency and selectivity of biorefineries. Here we discuss the factors that influence the interfacial charge transfer and radical reactions in photocatalytic biorefineries, including the surface structure and electronic states of semiconductors and the catalytic properties of cocatalysts.
Ruolan Zhang,¹ Zhenyuan Zhang,¹ Xuke Chen,¹ Jichun Jiang, Lei Hua, Xiuquan Jia,* Rui Bao,* and Feng Wang*
J. Am. Chem. Soc., 2024, DOI: 10.1021/jacs.4c00290
Surface waves are known for their mechanical role in coastal processes affecting weather and climate. However, their chemical impact, especially on pyrogenic carbon transformation, is poorly understood. Pyrogenic carbon is generally assumed to show negligible post-formation alteration of its stable carbon isotope composition. Here we present an electrochemical interaction of pyrogenic carbon with seawater microdroplets resulting from wave breaking, driven by galvanic coupling at the microdroplet water-carbon and the microdroplet water-vapor interfaces. This process allows refractory pyrogenic carbon to degrade rapidly through oxygenation and mineralization, enriching it in ¹³C (~2.6‰), which is beyond the assumed values (< 0.5‰). Seawater microdroplets' unique chemical dynamics provide new insights into carbon isotope discrepancies between riverine and marine black carbon, emphasizing coastal oceans' role in global carbon sequestration.
Yuting Liu, Beili Nie, Ning Li, Huifang Liu *, Feng Wang *
Chin. J. Catal., 2024, 58, 123-128.
The C(sp³)−H functionalization of naturally abundant alkanes is of great importance, whereas C−H bond oxidation of aryl ethers in a redox-neutral and environmental-friendly manner remains a challenge. Herein, we report a novel method of visible-light-driven C(sp³)−H bond oxidation of aryl ethers selectively into ester products using oxygen as the oxidant. During the photocatalytic reaction using Mes-10-phenyl-Acr⁺−BF₄⁻ catalyst, chlorine radicals are generated from a wide variety of chloride sources and can effectively activate aryl ether C(sp³)−H bonds into alkyl radicals through the hydrogen atom transfer (HAT) process. Aryl ethers with different substituents can be oxidized to esters in good to excellent yields. This work presents a new photocatalytic strategy for C(sp³)−H oxidation of aryl ethers in a convenient and green manner.
Min Wang, Hongru Zhou, Feng Wang
Recently, the team of Bioenergy Chemical Group (DNL0603) led by Prof. Wang Feng from the Dalian Institute of Chemical Physics (DICP) of the Chinese Academy of Sciences cooperated with the team of Prof. Wang Min from Dalian University of Technology was recently invited to prospect the topic about photocatalytic biomass conversion to hydrogen and carbon-based chemcials. The article was published in the Joule. This work was supported by the National Natural Science Foundation of China.