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Study on the catalytic degradation of sodium lignosulfonate to aromatic aldehydes over nano-CuO:Process optimization and Reaction kinetics

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Chinese Journal of Chemical Engineering 2023年第1期53卷 300-309页

作者： Yingjie Song Shuqi Zhong Yingjiao Li Kun Dong Yong Luo Guangwen Chu Haikui Zou Baochang Sun State Key Laboratory of Organic-Inorganic Composites Beijing University of Chemical TechnologyBeijing 100029China Research Center of the Ministry of Education for High Gravity Engineering and Technology Beijing University of Chemical TechnologyBeijing 100029China

As one of the few renewable aromatic resources,the research of depolymerization of lignin into highvalue chemicals has attracted extensive attention in recent years.Catalytic wet aerobic oxidation(CWAO)is an effective technology to convert lignin like sodium lignosulfonate(SL),a lignin derivative,into aromatic aldehydes such as vanillin and syringaldehyde.However,how to improve the yield of aromatic aldehyde and conversion efficiency is still a challenge,and many operating conditions that significantly affect the yield of these aromatic compounds have rarely been investigated systematically.In this work,we adopted the stirred tank reactor(STR)for the CWAO process with nano-CuO as catalyst to achieve the conversion of SL into vanillin and syringaldehyde.The effect of operating conditions including reaction time,oxygen partial pressure,reaction temperature,SL concentration,rotational speed,catalyst amount,and NaOH concentration on the yield of single phenolic compound was systematically investigated.The results revealed that all these operating conditions exhibit a significant effect on the aromatic aldehyde yield.Therefore,they should be regulated in an optimal value to obtain high yield of these aldehydes.More importantly,the Reaction kinetics of the lignin oxidation was explored.This work could provide basic data for the optimization and design of industrial operation of lignin oxidation.

关键词： Nano-CuO Sodium lignosulfonate Catalytic wet aerobic oxidation(CWAO) Aromatic aldehyde Reaction kinetics

Sulfite as the substrate of C-sulfonate metabolism ofα,β-unsaturated carbonyl containing andrographolide:analysis of sulfite in rats'intestinal tract and the Reaction kinetics of andrographolide with sulfite

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Chinese Journal of Natural Medicines 2021年第9期19卷 706-712页

作者： HUO Zhi-Peng FENG Xin-Chi WANG Yu TIAN Yu-Ting QIU Feng School of Chinese Materia Medica and State Key Laboratory of Component-based Chinese MedicineTianjin University of Traditional Chinese MedicineTianjin 301617China ~TCM Research Center Tasly AcademyTasly Holding Group Co.Ltd.Tianjin 300402China State Key Laboratory of Critical Technology in Innovative Chinese Medicine Tasly Pharmaceutical Co.Ltd.Tianjin 300402China Institute of Pharmacy China Pharmaceutical UniversityNanjing 210009China Institute of Pharmaceutical Science and Technology Tianjin UniversityTianjin 300072China

One-sixth of the currently known natural products containα,β-unsaturated carbonyl groups.Our previous studies reported a rare C-sulfonate metabolic pathway.Sulfonate groups were linked to theβ-carbon ofα,β-unsaturated carbonyl-based natural compounds through this pathway.However,the mechanism of this type of metabolism is still not fully understood,especially whether it is formed through enzyme-mediated biotransformation or direct sulfite addition.In this work,the enzyme-mediated and non-enzymatic pathways were studied.First,the sulfite content in rat intestine was determined by LC-MS/MS.The results showed that the amount of sulfite in rat intestinal contents was from 41.5 to 383μg·g^(-1),whereas the amount of sulfite in rat feed was lower than the lower limit of quantitation(20μg·g^(-1)).Second,the Reaction kinetics of sulfite-andrographolide reactions in phosphate buffer solutions(pH 6-8)was studied.The half-lives of andrographolide ranged from minutes to hours.This was suggested that the C-sulfonate reaction of andrographolide was very fast.Third,the C-sulfonate metabolites of andrographolide were both detected when andrographolide and L-cysteine-S-conjugate andrographolide were incubated with the rat small intestine contents or sulfite,indicating that the sulfite amount in rat intestine contents was high enough to react with andrographolide,which assisted a significant portion of andrographolide metabolism.Finally,the comparison of andrographolide metabolite profiles among liver homogenate(with NADPH),liver S9(with NADPH),small intestine contents homogenate(with no NADPH),and sulfite solution incubations showed that the C-sulfonate metabolites were predominantly generated in the intestinal tract by non-enzymatic pathway.In summary,sulfite can serve as a substrate for C-sulfonate metabolism,and these results identified non-enzymatically nucleophilic addition as the potential mechanism for C-sulfonate metabolism of compounds containingα,β-unsaturated carbonyl moiety.

关键词： Sulfite C-Sulfonate metabolites α,β-Unsaturated carbonyl Reaction kinetics Andrographolide Non-enzymatic

Empirical correction of kinetic model for polymer thermal reaction process based on first order Reaction kinetics

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Chinese Journal of Chemical Engineering 2021年第10期34卷 132-144页

作者： Zhaoxiang Zhang Fei Guo Wei Song Xiaohong Jia Yuming Wang State Key Laboratory of Tribology Tsinghua UniversityBeijing 100084China Joint Research Center for Rubber and Plastic Seals Tsinghua UniversityBeijing 100084China State Key Laboratory of Advanced Forming Technology&Equipment China Academy of Machinery Science&TechnologyBeijing 100044China Tianding Sealing Technology(Beijing)Co. Ltd.Beijing 100072China

Based on the theory of first-order Reaction kinetics,a thermal reaction kinetic model in integral form has been derive.To make the model more applicable,the effects of time and the conversion degree on the reaction rate parameters were considered.Two types of undetermined functions were used to compensate for the intrinsic variation of the reaction rate,and two types of correction methods are provided.The model was explained and verified using published experimental data of different polymer thermal reaction systems,and its effectiveness and wide adaptability were confirmed.For the given kinetic model,only one parameter needs to be determined.The proposed empirical model is expected to be used in the numerical simulation of polymer thermal reaction process.

关键词： Thermal reaction Polymer processing Reaction kinetics Mathematical modeling Empirical correction

Mitigated Reaction kinetics between lithium metal anodes and electrolytes by alloying lithium metal with low-content magnesium

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Journal of Energy Chemistry 2024年第8期95卷 644-650页

作者： Yang-Yang Wang Ya-Nan Wang Nan Yao Shu-Yu Sun Xiao-Qing Ding Chen-Xi Bi Qian-Kui Zhang Zhao Zheng Cheng-Bin Jin Bo-Quan Li Xue-Qiang Zhang Jia-Qi Huang School of Materials Science and Engineering Beijing Institute of Technology Advanced Research Institute of Multidisciplinary Science Beijing Institute of Technology Beijing Key Laboratory of Green Chemical reaction Engineering and Technology Department of Chemical Engineering Tsinghua University College of Materials and Chemistry China Jiliang University

Lithium(Li) metal is regarded as a promising anode candidate for high-energy-density rechargeable batteries. Nevertheless, Li metal is highly reactive against electrolytes, leading to rapid decay of active Li metal reservoir. Here, alloying Li metal with low-content magnesium(Mg) is proposed to mitigate the Reaction kinetics between Li metal anodes and electrolytes. Mg atoms enter the lattice of Li atoms, forming solid solution due to the low amount(5 wt%) of Mg. Mg atoms mainly concentrate near the surface of Mg-alloyed Li metal anodes. The reactivity of Mg-alloyed Li metal is mitigated kinetically, which results from the electron transfer from Li to Mg atoms due to the electronegativity difference. Based on quantitative experimental analysis, the consumption rate of active Li and electrolytes is decreased by using Mgalloyed Li metal anodes, which increases the cycle life of Li metal batteries under demanding conditions.Further, a pouch cell(1.25 Ah) with Mg-alloyed Li metal anodes delivers an energy density of 340 Wh kg-1and a cycle life of 100 cycles. This work inspires the strategy of modifying Li metal anodes to kinetically mitigate the side reactions with electrolytes.

关键词： Alloying Anode/electrolyte interface Lithium metal anodes Pouch cell Reaction kinetics

Insight into pyrolysis of hydrophobic silica aerogels:kinetics,reaction mechanism and effect on the aerogels

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Chinese Journal of Chemical Engineering 2023年第6期58卷 266-281页

作者： Xinyu Liu Hongliang Sheng Song He Chunhua Du Yuansheng Ma Chichi Ruan Chunxiang He Huaming Dai Yajun Huang Yuelei Pan School of Safety Science and Emergency Management Wuhan University of TechnologyWuhan 430070China Wuhan Building Material Industry Design&Research Institute Co. LtdWuhan 430200China State Key Laboratory of Fire Science University of Science and Technology of ChinaHefei 230027China

Silica aerogels have promising applications in thermal insulation,but their flammability and reaction mechanisms have rarely been investigated.The pyrolysis kinetics and thermodynamics of hydrophobic silica aerogels under N_(2) environment were studied.The kinetic and thermodynamic parameters were obtained by three model-free methods.Based on the calculated kinetic parameters,the pyrolysis mechanism of silica aerogels was discussed by the master plots method.The results indicate that the reactions of the whole pyrolysis phase can be characterized by a random nuclear model.In addition,FTIR test results show that the volatile products of silica aerogel pyrolysis are mainly hydrocarbons generated by the decomposition of hydrophobic groups(methyl groups)on the surface.Finally,the effects of pyrolysis on the properties of silica aerogels Finally,the effects of pyrolysis on the properties of silica aerogels were investigated based on the analysis results of SEM,specific surface area,pore size distribution,X-ray diffraction,XPS and infrared spectroscopy.

关键词： Pyrolysis Thermodynamics Reaction kinetics

kinetics and mechanism of titanium hydride powder and aluminum melt reaction

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International Journal of Minerals,Metallurgy and Materials 2012年第2期19卷 165-172页

作者： Ali Rasooli Mehdi Divandari Hamid Reza Shahverdi Mohammad Ali Boutorabi School of Metallurgy and Materials Engineering Member of Center of Excellence for Advanced Material and Processing (CEAMP) Iran University of Science and Technology Tehran 16844 Iran Department of Materials Faculty of Engineering Tarbiat Modaress University Tehran 14115-143 Iran

Based on the measurement of the released hydrogen gas pressure （PH2）, the Reaction kinetics between TiH2 powder and pure aluminum melt was studied at various temperatures. After cooling the samples, the interface of TiH2 powder and aluminum melt was studied. The results show that the-time curves have three regions; in the first and second regions, the rate of reaction conforms zero and one order, respectively; in the third region, the hydrogen gas pressure remains constant and the rate of reaction reaches zero. The main factors that control the rate of reaction in the first and second regions are the penetration of hydrogen atoms in the titanium lattice and the chemical reaction between molten aluminum and titanium, respectively. According to the main factors that control the rate of reaction, three temperature ranges are considered for the reaction mechanism：（a） 700-750°C, （b） 750-800°C, and （c） 800-1000°C. In the first temperature range, the reaction is mostly under the control of chemical reaction; at the temperature range of 750 to 800°C, the reaction is controlled by the diffusion and chemical reaction; at the third temperature range （800-1000°C）, the dominant controlling mechanism is diffusion.

关键词： titanium hydride aluminum Reaction kinetics reaction rate constants

Oxidation of diclofenac by potassium ferrate(Ⅵ): Reaction kinetics and toxicity evaluation

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Oxidation of diclofenac by potassium ferrate(Ⅵ): Reaction k...

Multi-Dimensional Composite Frame as Bifunctional Catalytic Medium for Ultra-Fast Charging Lithium-Sulfur Battery

河南省化学会2016年学术年会

作者： Yingling Wang Youhai Xie Haijin Liu Guoguang Liu Key Laboratory of Medical Molecular Probes School of Basic Medical Sciences Xinxiang Medical University School of Environment Henan Normal University Key Laboratory for Yellow River and Huaihe River Water Environment and Pollution Control

Diclofenac(DCF), a synthetic non-steroidal anti-inflammatory drug, is widely detected in ambient surface water and sewage treatment effluent. There is a growing concern regarding the persistence of DCF in the environment and its potential adverse impacts. Thus, it will be a serious threat to public health and ecosystems if drinking water sources are contaminated with DCF.Ferrate(Ⅵ) has been widely used in potable water treatment due to its triple functions as an oxidant,coagulant and disinfectant. Although ferrate is a currently utilized as an oxidant for the removal of micropollutants from aqueous media, the degradation of DCF by Fe(Ⅵ) has rarely been investigated.Furthermore, further studies are required to assess the changes in toxicity of the reaction solutions.In this work, the Reaction kinetics and toxicity of diclofenac(DCF) oxidation by ferrate(Ⅵ) under simulated water disinfection conditions were investigated. Experimental results indicated that the reaction between DCF and Fe(Ⅵ) followed first-order kinetics with respect to each reactant.Furthermore, the effects of p H and temperature on DCF oxidation by Fe(Ⅵ) were elucidated via a systematic examination. The apparent second-order rate constants(kapp) increased significantly from2.54 to 11.6 M s, as the p H of the solution decreased from 11.0 to 7.0, and the acid-base equilibriums of Fe(Ⅵ) and DCF were proposed to explain the p H dependence of kapp. The acute toxicity of DCF solution during Fe(Ⅵ) oxidation was evaluated using a Microtox bioassay. Overall, the DCF degradation process resulted in a rapid increase of the inhibition rate of luminescent bacteria. These toxicity tests suggest that the formation of enhanced toxic intermediates during the Fe(Ⅵ) disinfection process may pose potential health risk to consumers.

关键词： Diclofenac Ferrate（Ⅵ） Reaction kinetics Toxicity

来源： cnki会议评论

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Nano-Micro Letters 2022年第12期14卷 91-105页

作者： Shuhao Tian Qi Zeng Guo Liu Juanjuan Huang Xiao Sun Di Wang Hongcen Yang Zhe Liu Xichao Mo Zhixia Wang Kun Tao Shanglong Peng National and Local Joint Engineering Laboratory for Optical Conversion Materials and Technology School of Materials and EnergyLanzhou UniversityLanzhou 730000People’s Republic of China School of Physical Science and Technology Lanzhou UniversityLanzhou 730000People’s Republic of China

The shuttle effect of soluble lithium polysulfides(LiPSs)between electrodes and slow Reaction kinetics lead to extreme inefficiency and poor high current cycling stability,which limits the commercial application of Li-S batteries.Herein,the multi-dimensional composite frame has been proposed as the modified separator(MCCoS/PP)of Li-S battery,which is composed of CoS_(2) nanoparticles on alkali-treated MXene nanosheets and carbon nanotubes.Both experiments and theoretical calculations show that bifunctional catalytic activity can be achieved on the MCCoS/PP separator.It can not only promote the liquid-solid conversion in the reduction process,but also accelerate the decomposition of insoluble Li_(2)S in the oxidation process.In addition,LiPSs shuttle effect has been inhibited without a decrease in lithium-ion transference numbers.Simultaneously,the MCCoS/PP separator with good LiPSs adsorption capability arouses redistribution and fixing of active substances,which is also beneficial to the rate performance and cycling stability.The Li-S batteries with the MCCoS/PP separator have a specific capacity of 368.6 mAh g^(−1) at 20C,and the capacity decay per cycle is only 0.033%in 1000 cycles at 7C.Also,high area capacity(6.34 mAh cm^(−2))with a high sulfur loading(7.7 mg cm^(−2))and a low electrolyte/sulfur ratio(7.5μL mg^(−1))is achieved.

关键词： MXenes Transition metal sulfides Lithium-ion transference Bifunctional catalysis Reaction kinetics

Effect of solvent on the initiation mechanism of living anionic polymerization of styrene: A computational study

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CHINESE JOURNAL OF CHEMICAL ENGINEERING 2024年第5期69卷 135-142页

作者： Li, Shen Zhou, Yin-Ning Liu, Zhong-Xin Luo, Zheng-Hong Hainan Univ Sch Chem Engn & Technol Haikou 570228 Peoples R China Shanghai Jiao Tong Univ Sch Chem & Chem Engn Dept Chem Engn State Key Lab Met Matrix Composites Shanghai 200240 Peoples R China

For living anionic polymerization (LAP), solvent has a great in fluence on both reaction mechanism and kinetics. In this work, by using the classical butyl lithium-styrene polymerization as a model system, the effect of solvent on the mechanism and kinetics of LAP was revealed through a strategy combining density functional theory (DFT) calculations and kinetic modeling. In terms of mechanism, it is found that the stronger the solvent polarity, the more electrons transfer from initiator to solvent through detailed energy decomposition analysis of electrostatic interactions between initiator and solvent molecules. Furthermore, we also found that the stronger the solvent polarity, the higher the monomer initiation energy barrier and the smaller the initiation rate coef ficient. Counterintuitively, initiation is more favorable at lower temperatures based on the calculated results of D G TS . Finally, the kinetic characteristics in different solvents were further examined by kinetic modeling. It is found that in benzene and n - pentane, the polymerization rate exhibits first-order kinetics. While, slow initiation and fast propagation were observed in tetrahydrofuran (THF) due to the slow free ion formation rate, leading to a deviation from first-order kinetics. (c) 2024 The Chemical Industry and Engineering Society of China, and Chemical Industry Press Co., Ltd. All rights reserved.

关键词： Living anionic polymerization Solvent effect Reaction kinetics Computational chemistry Mathematical modeling Kinetic modeling kinetics SOLVATION MONOMERS AGGREGATION SIMULATION PREDICTION MOLECULE LITHIUM