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Tuning the selectivity of natural oils and fatty acids/esters deoxygenation to biofuels and fatty alcohols:A review

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Green Energy & Environment 2023年第3期8卷 722-743页

作者： Yingdong Zhou Javier Remon Zhicheng Jiang Avtar S.Matharu Changwei Hu Key Laboratory of Green Chemistry and Technology Ministry of EducationCollege of ChemistrySichuan UniversityChengduSichuan 610064China Instituto de Carboquímica CSICZaragoza50018Spain Department of Biomass Science and Engineering Sichuan UniversityChengdu610064China National Engineering Research Center of Clean Technology in Leather Industry Sichuan UniversityChengdu610064China Green Chemistry Centre of Excellence Department of ChemistryUniversity of YorkHeslingtonYorkYO105DDUK

The chemical transformation of natural oils provides alternatives to limited fossil fuels and produces compounds with added value for the chemical industries.The selective deoxygenation of natural oils to diesel-ranged hydrocarbons,bio-jet fuels,or fatty alcohols with controllable selectivity is especially attractive in natural oil feedstock biorefineries.This review presents recent progress in catalytic deoxygenation of natural oils or related model compounds(e.g.,fatty acids)to renewable liquid fuels(green diesel and bio-jet fuels)and valuable fatty alcohols(unsaturated and saturated fatty alcohols).Besides,it discusses and compares the existing and potential strategies to control the product selectivity over heterogeneous catalysts.Most research conducted and reviewed has only addressed the production of one category;therefore,a new integrative vision exploring how to direct the process toward fuel and/or chemicals is urgently needed.Thus,work conducted to date addressing the development of new catalysts and studying the influence of the reaction parameters(e.g.,temperature,time and hydrogen pressure)is summarized and critically discussed from a green and sustainable perspective using efficiency indicators(e.g.,yields,selectivity,turnover frequencies and catalysts lifetime).Special attention has been given to the chemical transformations occurring to identify key descriptors to tune the selectivity toward target products by manipulating the reaction conditions and the structures of the catalysts.Finally,the challenges and future research goals to develop novel and holistic natural oil biorefineries are proposed.As a result,this critical review provides the readership with appropriate information to selectively control the transformation of natural oils into either biofuels and/or value-added chemicals.This new flexible vision can help pave the wave to suit the present and future market needs.

关键词： Natural oil deoxygenation Controllable selectivity Biofuels Fatty alcohols

A New deoxygenation Method for Taxanes Using Hypophosphorous Acid

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Chinese Chemical Letters 2004年第6期15卷 649-651页

作者： JunGU MengZHANG DaLiYIN JiYuGUO XiaoTianLIANG InstituteofMateriaMedica ChineseAcademyofMedicalSciences＆PekingUnionMedicalCollegeBeijing100050

An efficient and practical radical chain deoxygenation method by phosphorus centered radicals generated from hypophosphorous acid was developed in the synthesis of analogues of paclitaxel.

关键词： deoxygenation taxanes hypophosphorous acid.

Catalytic Pyrolysis of Soybean Oil with CaO/Bio-Char Based Catalyst to Produce High Quality Biofuel

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Journal of Renewable Materials 2022年第12期10卷 3107-3118页

作者： Lujiang Xu Geliang Xie Xianjun Zhou Yucheng Liu Zhen Fang Biomass Group College of EngineeringNanjing Agricultural UniversityNanjing210031China

In this paper,CaO/bio-char was synthesized by directly co-pyrolysis of Ca(OH)_(2) and rice straw,and used as catalyst to catalytic pyrolysis of soybean oil to produce high quality biofuel.In this co-pyrolysis process,CaO particles has been successfully embedded on the bio-char surface.During the catalytic pyrolysis process,CaO/biochar showed a good catalytic performance on the deoxygenation of soybean oil.Pyrolysis temperature affected the pyrolysis reactions and pyrolytic products distributions dramatically,higher pyrolysis temperature lead to seriously cracking reactions,lower bio-oil yield and higher gases yield,and lower pyrolysis temperature lead to higher bio-oil yield with higher oxygenated compounds content and lower hydrocarbons contents,the suitable pyrolysis temperature was around 650℃.Under the optimal conditions(650℃ with WHSV at 6.4 h^(−1) and carrier gas flow rate at 100 ml/min),the selectivity(%)of hydrocarbons in the bio-oil was more than 90%.CaO/bio-char catalyst still shows good catalytic deoxygenation activity after 4 cycles.1 g of CaO/bio-char catalyst can catalyze pyrolysis of 32 g of soybean oil to produce high-quality liquid fuel.Bio-char based catalyst has been proved to be a promising catalyst for catalytic conversion of triglyceride-based lipids into high quality liquid biofuel.

关键词： Carbonization CaO/bio-char catalytic pyrolysis deoxygenation high quality biofuel

Cyclopropanation Versus deoxygenation in the Reactions of Halocarbenes with pre-Aromatic Ketones

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Chinese Chemical Letters 1999年第4期10卷 271-272页

作者： Wang, HX Zhang, GJ Gu, WX Huan, ZW Cheng, JP Nankai Univ Dept Chem Tianjin 300071 Peoples R China

The reactions of halocarbenes with pre-aromatic ketones 1, 2 resulted in cyclopropanation and deoxygenation products. The varying product ratio could be accounted for by a mechanism involving the carbonyl ylide interm... 详细信息

关键词： halocarbene deoxygenation cyclopropanation mechanism

Studies on the Aromatic Dihalocarbonyl Ylides and Their deoxygenation

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Chemical Research in Chinese Universities 1989年第1期5卷 41-49页

作者： Huan Zhenwei, Pan Yinming, Qu Xiaosu and Gao Zhenheng (Department of Chemistry, Nankai University, Tianjin)

The deoxygenation reaction of heptanones, cycloheptanone, cycloheptatrienone or substituted cycloheptatrienone with dihalo-carbene results in carbon monoxide and corresponding halides. The yield of CO produced by 2 , 4 , 6-triphenylcycloheptatrienone is 2.6-3.5 times as high as that produced by the saturated heptanones. The structures, energies, charge distributions, bond orders, and other relative parameters of the dihalocarbonyl glides were calculated by using the SCF-MNDO method. The obtained data reveal that the ylides from cycloheptatrienone have aromatic structure and are different from those produced from saturated cycloheptanone. The reactivities of the dihalocarbonyl ylides are discussed. It is proposed that this aromatic structure should be responsible for the high yield of CO from the reaction of cycloheptatrienone with dihalocarbene.

关键词： Carbonyl ylide deoxygenation Aromaticity.

Visible-light-driven Cadogan reaction

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Chinese Chemical Letters 2021年第8期32卷 2582-2586页

作者： Zhonghua Qu Pu Wang Xing Chen Guo-Jun Deng Huawen Huang Key Laboratory for Green Organic Synthesis and Application of Hunan Province Key Laboratory of Environmentally Friendly Chemistry and Application of Ministry of EducationCollege of ChemistryXiangtan UniversityXiangtan 411105China

Visible-light-driven photochemical Cadogan-type cyclization has been discovered.The organic D-A type photosensitizer 4 CzIPN found to be an efficient mediator to transfer energy from photons to the transient intermediate that breaks the barriers of deoxygenation in Cadogan reaction and enables a mild metalfree access to carbazoles and related heterocycles.DFT calculation results indicate mildly endergonic formation of the intermediate complex of nitrobiarenes and PPh3,which corresponds with experimental findings regarding reaction temperature.The robust synthetic capacity of the photoredox Cadogan reaction systems has been demonstrated by the viable productivity of a broad range of carbazoles and related N-heterocycles with good tolerance of various functionalities.

关键词： Cadogan reactio o-Nitrobiarene Visible-light-driven deoxygenation N-Heterocycles

Selective preparation of light aromatic hydrocarbons from catalytic fast pyrolysis vapors of coal tar asphaltene over transition metal ion modified zeolites

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Chinese Journal of Chemical Engineering 2021年第7期34卷 275-287页

作者： Yongqi Liu Qiuxiang Yao Ming Sun Xiaoxun Ma School of Chemical Engineering Northwest UniversityInternational Science&Technology Cooperation Base of MOST for Clean Utilization of Hydrocarbon ResourcesChemical Engineering Research Center of the Ministry of Education for Advanced Use Technology of Shanbei EnergyShaanxi Research Center of Engineering Technology for Clean Coal ConversionCollaborative Innovation Center for Development of Energy and Chemical Industry in Northern ShaanxiXi’an 710069China

The catalytic cracking of coal tar asphaltene(CTA)pyrolysis vapors was carried out over transition metalion modified zeolites to promote the generation of light aromatic hydrocarbons(L-ArHs)in a pyrolysisgas chromatography/mass spectrometry(Py-GC/MS)micro-reactor system.The effects of ultra stable Y(USY),Co/USY and Mo/USY on the selectivity and yield of L-ArHs products and the extent of deoxygenation(Edeoxygenation),lightweight(Elightweight)from CTA pyrolysis volatiles were investigated.Results showed that the yields of L-ArHs are mainly controlled by the acid sites and specific surface area of the catalysts,while the deoxygenation effect is determined by theirs pore size.The Eligltweight of CTA pyrolysis volatiles over USY is 9.65%,while the Edeoxygenation of CTA pyrolysis volatiles over Mo/USY reaches 20.85%.Additionally,the modified zeolites(Mo/USY and Co/USY)exhibit better performance than USY on L-ArHs production,owing to the synergistic effect of metal ions(Mo,Co)and acid sites of USY.Compared with the non-catalytic fast pyrolysis of CTA,the total yield of L-ArHs obtained over USY(4032 mg·kg^(-1)),Co/USY(4363 mg·kg^(-1))and Mo/USY(4953 mg·kg^(-1))were increased by 27.03%,38.19%and 54.78%,respectively.Furthermore,the possible catalytic conversion mechanism of transition metal ion(Co and Mo)modified zeolites was proposed based on the distribution of products and the characterizations of catalysts.

关键词： Coal tar asphaltene Transition metal ion modification deoxygenation Lightweight Light aromatic compounds

Mechanism of dibenzofuran hydrodeoxygenation on the Ni(1 1 1)surface

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Chinese Journal of Chemical Engineering 2021年第7期34卷 204-210页

作者： Zi-Zheng Xie Meng Zhang Xing-Bao Wang Liang Guo Zhen-Yi Du Wen-Ying Li State Key Laboratory of Clean and Efficient Coal Utilization Taiyuan University of TechnologyKey Laboratory of Coal Science and Technology(Taiyuan University of Technology)Ministry of EducationTaiyuan 030024China

The low-temperature coal tar contains a considerable number of oxygen-containing compounds,which results in poor quality.The catalytic hydrodeoxygenation of oxygen-containing compound to an added-value chemical compound is one of the most efficient methods to upgrade coal tar.In this study,density functional theory calculations are employed to assess and analyze in detail the hydrodeoxygenation of dibenzofuran,as a model compound of coal tar,on the Ni(111)surface.The obtained results indicate that dibenzofuran can be firstly hydrogenated to tetra hy d rod i be nzofura n and hexahydfodibenzofufan.The five-membered-ring opening reaction of tetrahydrodibenzofuran is more straightforward than that of hexahydrodibenzofuran(Ea=0.71 eV vs.1.66 eV).Then,both pathways generate an intermediate 2-cyclohexylphenoxy compound.One part of 2-cyclohexylphenoxy is hydrogenated to 2-cyclohexylphenol and consecutively hydrogenated to cyclohexylcyclohexanol,and another part is directly hydrogenated to cyclohexylcyclohexanone.The hydrogenated intermediates of2-cyclohexylphenol have higher deoxygenation barriers than 2-cyclohexylphenol and cyclohexylcy clohexanol.During the hydrogenation process of cyclohexylcyclohexanone to cyclohexylcyclohexanol,the intermediate 26,formed by adding H to O atom of cyclohexylcyclohexanone,exhibits the lowest deoxygenation barrier of 1.08 eV.High hydrogen coverage may promote the hydrogenation of tetrahydrodibenzofuran,hexahydrodibenzofuran,and intermediate 26 to generate dodecahydrodibenzofuran and cyclohexylcyclohexanol.This dibenzofuran hydrodeoxygenation reaction mechanism corroborates well with previous experimental results and provides a theoretical basis for further optimization of the design of nickel-based catalysts.

关键词： Oxygen-containing compound Hydrogenation deoxygenation Catalysis Computational chemistry

Climate tipping-point potential and paradoxical production of methane in a changing ocean

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Science China Earth Sciences 2018年第12期61卷 1714-1727页

作者： Hongyue DANG Jia LI State Key Laboratory of Marine Environmental Science Institute of Marine Microbes and EcospheresCollege of Ocean and Earth SciencesXiamen UniversityXiamen 361102China Tianjin Branch of China National Offshore Oil Corporation Ltd Tianjin 300452China

The global warming potential of methane(CH_4) is about 30 times stronger than that of carbon dioxide(CO2) over a century timescale. Methane emission is hypothesized to have contributed to global climate change events and mass extinctions during Earth's history. Therefore, the study of CH_4 production processes is critically important to the understanding of global climate change. It has been a dogma that biogenic CH_4 detectable in the oceans originates exclusively from the anaerobic metabolic activity of methanogenic archaea in hypoxic and anoxic environments, despite reports that many oxic surface and near-surface waters of the world's oceans are CH_4-supersaturated, thereby rendering net sea-to-air emissions of CH_4. The phenomenon of CH_4 production in oxic marine waters is referred to as the "ocean methane paradox". Although still not totally resolved, recent studies have generated several hypotheses regarding the sources of CH_4 production in oxic seawater. This review will summarize our current understanding of the importance of CH_4 in the global climate and analyze the biological processes and their underpinning mechanisms that lead to the production of CH_4 in oxic seawater environments. We will also tentatively explore the relationships of these microbial metabolic processes with global changes in climate and environment.

关键词： Ocean methane paradox Gas hydrate Marine particles Methylphosphonate DSMP Global warming Ocean deoxygenation Ocean acidification