Data
·
2021
·Vol. 6
·期 3
·24
·
IF 0
William Bains,Janusz Jurand Petkowski,Sara Seager
We describe a dataset of the quantitative reactivity of organic chemicals with concentrated sulfuric acid. As well as being a key industrial chemical, sulfuric acid is of environmental and planetary importance. In the absence of measured reaction kinetics, the reaction rate of a chemical with sulfuric acid can be estimated from the reaction rate of structurally related chemicals. To allow an approximate prediction, we have collected 589 sets of kinetic data on the reaction of organic chemicals with sulfuric acid from 262 literature sources and used a functional group-based approach to build a model of how the functional groups would react in any sulfuric acid concentration from 60–100%, and between −20 °C and 100 °C. The data set provides the original reference data and kinetic measurements, parameters, intermediate computation steps, and a set of first-order rate constants for the functional groups across the range of conditions −20 °C–100 °C and 60–100% sulfuric acid. The dataset will be useful for a range of studies in chemistry and atmospheric sciences where the reaction rate of a chemical with sulfuric acid is needed but has not been measured.Dataset:doi: 10.5281/zenodo.4467868Dataset License:Dataset is made available under the Creative Commons license CC BY (SA).Keywords:kinetics;reactivity;sulfuric acid;sulfonation;solvolysis
研究领域:
化学
·
大气科学
✓ 已验证
DOI
POLYMERS FOR ADVANCED TECHNOLOGIES
·
2024
·Vol. 35
·期 1
·e6277
·
IF 3.1
Anqi Ming,Xiaoxiao Li,Jun Sun,Yanyan Liu,Xingyou Tian,Hua Wang,Lin Chen,Yuxiang Cao,Yun Yuan
The cationic water-soluble polymers, which are widely used in many areas such as papermaking and separation process, are typically synthesized through polymerization of cationic monomers represented by quaternary ammonium salt. In this work, the polymerization reaction kinetics of three typical quaternary ammonium salt cationic monomers including acryloyl oxygen ethyl trimethyl ammonium chloride (DAC), methyl acryloyl oxygen ethyl trimethyl ammonium chloride (DMC), and methyl acrylamide propyl trimethyl ammonium chloride (MAPTAC) was examined by using the dilatometer method. The results showed that the polymerization rate of all three monomers increased with the increase of initiation temperature, monomer concentration, and initiator concentration. Under the same conditions, the polymerization activity of the three monomers followed the order: DAC > DMC > MAPTAC. The activation energies for the polymerization reaction under the specified conditions were E aDAC = 138.97 kJ/mol, E aDMC = 141.24 kJ/mol, and E aMAPTAC = 226.97 kJ/mol, respectively. The polymerization rate equations were R pDAC = k 1 [ M ] 4.25 [ I ] 0.51 , R pDMC = k 2 [ M ] 3.77 [ I ] 0.50 , and R pMAPTAC = k 3 [ M ] 3.30 [ I ] 0.49 . The polymerization activity of the monomers may be influenced by electronic effects and steric hindrance of the monomer structure. This work has provided a theoretical and experimental foundation for the actual work of structural design and preparation of cationic water-soluble polymers.
研究领域:
高分子化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2020
·
IF 4.939
Yinghui Sun,Guojie Zhang,Haizhu Cheng,Jun Liu,Guoqiang Li
The mechanism and kinetic features of dry reforming with methane (DRM) over Ca promoted 1Co–1Ce/AC-N catalyst was investigated. The mechanistic pathway studies have conducted by FTIR and XPS analysis, structure-activity correlations demonstrated the CH 4 and CO 2 could adsorb on catalyst active sites and generate intermediate CH x , OH and CH x O, continue to generate CO and H 2 and then desorbed from active sites. Moreover, CH 4 could also oxidized by Ce 4+ and CO 2 reduced by Ce 3+ , the same content of Ce 4+ and Ce 3+ on promoted catalyst greatly improved the reaction rate. The kinetic of dry reforming with methane was examined for temperature between 650 and 850 at 800 °C. The research was carried out by changing the CH 4 /CO 2 ratios between 0.3 and 3.0. The obtained experiment data were fitted by three typical kinetic models (Power Law, Eley-Rideal and Langmuir-Hinshelwood), the fitting results demonstrated that the best prediction of reforming rates can provided by Langmuir-Hinshelwood model for the reaction temperatures between 650 and 800 °C. Moreover, activation energies of methane and carbon dioxide consumption were −117 and −47 kJ/mol, indicating that much higher energy barrier is needed for methane activation compared to carbon dioxide.
研究领域:
化学工程
·
催化科学
✓ 已验证
产品关联
DOI
高影响因子
CHEMOSPHERE
·
2020
·
IF 5.778
Jianjun Lian,Heli Wang,Hongping He,Weilin Huang,Mei Yang,Yin Zhong,Ping’an Peng
Iron sulfide (FeS) is an important scavenger for hexavalent molybdate (Mo(VI)) in an anoxic environment; it plays a crucial role in the mobilization and transformation of Mo(VI), although the underlying reaction mechanisms between Mo(VI) and FeS remain unclear. This study investigates the Mo(VI) reaction kinetics with the amorphous FeS over a pH range 5.0–9.0 and Mo’s chemical form on the FeS surface. It is found that the Mo(VI) reaction kinetics with FeS follow a pseudo first-order model, and the reaction rate constant ( k obs ) increases with a decrease in the pH value. The k obs at pH 5.0 is 0.027 min −1 , which is about 38 times higher than that at pH 9.0. The rapid Mo(VI) removal under acidic conditions is due to quick Mo(VI) transformation into stable MoS 2 and thiomolybdate (Mo V O x S y ). The amount of MoS 2 formed on the surface of FeS increases with a decrease in the pH value. Under neutral and alkaline conditions, Mo(VI) is not transformed into MoS 2 by FeS because the precipitation of iron oxy-hydroxide passivates the active sites of FeS. The study also investigates the effect of the initial dosage of FeS (20–200 mg L −1 ) and Mo(VI) (10–50 mg L −1 ) on the reaction kinetics of Mo(VI) with FeS. The results provides important information on the environmental fate of Mo(VI) in the anoxic environment containing amorphous FeS.
研究领域:
环境科学
·
地球化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
WASTE MANAGEMENT
·
2019
·
IF 5.431
Chenyu Wang,Wei Zhu,Hao Zhang,Cheng Chen,Xihui Fan,Ying Su
The hydrothermal gasification of dewatered sewage sludge converts waste into syngas fuel (gas containing H 2 , CH 4 , CO, and CO 2 ), but the formation of char and tar by a side reaction restricts practical applications. In this study, the formation of char/tar by the hydrothermal gasification of dewatered sewage sludge at 300–400 °C for 5–90 min with a heating rate of 8–50 °C/min is investigated. The results showed that the formation of tar/char reached equilibrium after 30 min, and an increase in the temperature and heating rate reduced the char yield. However, a higher tar yield was achieved at the highest temperature. Experiments on sludge with different moisture contents were also conducted, and the formation of char/tar was inhibited at a higher moisture content. The addition of NaOH and H 2 O 2 can effectively reduce the char and tar yields, respectively. A lumped kinetic model for describing carbon conversion during the hydrothermal gasification of sewage sludge was developed to elucidate the char/tar formation mechanism. The experimental data were used to determine the model parameters, and the fitting results showed that solid–solid conversion from organic matter in sludge was the predominant char/tar formation pathway, with an activation energy of 7.1 kJ/mol. The experiments using the model compounds indicated that humus and protein are the main precursors of char and tar, respectively. This study provides insights for understanding the formation of char/tar from sewage sludge following hydrothermal gasification, which is vital for controlling the formation of char and tar to improve the gasification efficiency.
研究领域:
环境科学
·
能源工程
✓ 已验证
DOI
PubMed
高影响因子
RSC Advances
·
2015
·Vol. 5
·期 125
·103203-103209
·
IF 3.84
Qin Zhang,Po Yang,Yuyuan Deng,Chengxi Zhang,Rongqi Zhu,Yi Gu
This work aims to search the key starting materials and the key step of benzoxazine synthesis using primary amine, phenol and formaldehyde as the starting materials. The reaction kinetics were investigated by gas chromatography. The kinetic parameters of benzoxazine formation, such as reaction order, rate constant and activation energy, were found to approximately equal those of phenol consumption, which revealed that phenol was the key starting material and played an important role in the synthesis of benzoxazine. Furthermore, step 2, the reaction between formaldehyde–amine derivatives and phenol for the production of a mannich base was the controlling step. This improved insight into the benzoxazine synthesis is expected to help researchers explore novel benzoxazines and control their synthesis.
研究领域:
化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
ORGANIC PROCESS RESEARCH & DEVELOPMENT
·
2016
·
IF 2.922
Yiying Zhang,Dongxiang Zhang,Kai Dong,Penghao Lv,Siping Pang,Chenghui Sun
The kinetics of the nitration reaction of 2,6,8,12-tetraacetyl-4,10-dinitro-2,4,6,8,10,12-hexaazaisowurtzitane (TADN) in HNO3–H2SO4 nitrating agent has been studied. The reaction network of the nitration reaction is constructed according to analysis of the experimental results. A kinetics model is introduced and the kinetics parameters are estimated by data fitting. Statistical analysis verifies that the kinetics model is in good agreement with the experimental data. Therefore, the reaction kinetics model can be applied to process analysis and scale-up of nitration of TADN to 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane (HNIW).
研究领域:
化学动力学
·
有机化学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING SCIENCE
·
2024
·
IF 4.1
Zhaohua Jiang,Jinjin Wen,Huiting Xu,Yufen Zhang,Haonan Zhai,Zhijie Cui,Honghai Wang,Junjie Qi,Wen Liu,Jiapeng Liu
Aqueous zinc-tellurium (Zn-Te) batteries based on conversion reactions between Zn and Te have sparked significant interest due to their cost-effectiveness, high theoretical specific capacity and outstanding safety features. Nevertheless, the sluggish kinetics pose a barrier to the advancement of aqueous Zn-Te batteries. In this study, zero-dimension (0D) nanodots and three-dimensional (3D) nanoflowers molybdenum diselenide (MoSe 2 ) are in situ grown on the holey reduced graphene oxide (HrGO) by a confinement synthesis strategy. Benefiting from the simultaneous presence of (0D/3D)MoSe 2 , excellent conductivity of holey reduced graphene oxide and unique hierarchical structure, the (0D/3D)MoSe 2 @HrGO hybrid greatly promotes the redox kinetics between Zn and Te conversion. Consequently, the constructed aqueous Zn-Te batteries equipped with a Te@(0D/3D)MoSe 2 @HrGO cathode demonstrate remarkable specific capacity (reaching 505 mAh/g at a current density of 0.15 A/g) along with outstanding long-term cycling stability. Additionally, the underlying conversion mechanism has been meticulously explored through extensive analytical techniques. This research introduces an innovative approach to boost the electrochemical performance of aqueous zinc-tellurium batteries.
研究领域:
材料科学
·
能源存储
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
CHEMOSPHERE
·
2020
·
IF 5.778
Jie Zhao,Qiang Song,Qiang He,Dionysios D. Dionysiou,Fei Wu,Yawei Feng,Xinying Zhang
The design of eco-friendly Bi 1.81 MnNbO 6.72 /sulfite system for efficient degradation of chlortetracycline was achieved. The feasibility of synthesizing Bi 1.81 MnNbO 6.72 by hydrothermal method was determined by X-ray diffraction. The magnetic test suggested that Bi 1.81 MnNbO 6.72 possessed paramagnetic properties, indicating unpaired electrons were present. Scanning electron microscope and transmission electron microscopy images revealed that Bi 1.81 MnNbO 6.72 octahedra exhibited exposed [1,1,1] crystal plane containing high density of Bi, Mn and Nb metal atoms. Large numbers of metal atoms will facilitate heterogeneous catalytic process. In a batch system with aeration, Bi 1.81 MnNbO 6.72 could be used as sulfite activator for the disposal of chlortetracycline. The reaction kinetics of the degradation process conformed to the pseudo-second-order kinetic model. In Bi 1.81 MnNbO 6.72 /sulfite process, initial pH, Bi 1.81 MnNbO 6.72 dosage, sulfite and chlortetracycline concentrations, as well as inorganic salt ions had great effect on chlortetracycline degradation. Under optimal conditions, the efficiency of Bi 1.81 MnNbO 6.72 /sulfite system for degradation of chlortetracycline could reach 76.2%. Moreover, Mn (II) plays a key role in the initiation of the catalytic reaction in Bi 1.81 MnNbO 6.72 /sulfite process. Generated SO 3 ●‒ could act as main reactive species in Bi 1.81 MnNbO 6.72 /sulfite process, while HO ● was also involved. Three new degradation products were detected by UHPLC/MS/MS and the possible degradation pathways in this system were proposed. Based on this, we believe that Bi 1.81 MnNbO 6.72 /sulfite is a type of process for degradation of organic contaminants with research significance and application prospects.
研究领域:
环境科学
·
催化化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Nanoscale
·
2019
·Vol. 11
·期 15
·7465-7473
·
IF 6.97
Meng Zhang,Xuezhang Xiao,Xinwei Wang,Man Chen,Yunhao Lu,Meijia Liu,Lixin Chen
Transition metal compounds are one of the highly efficient types of catalyst for improving the reaction kinetics of hydrogen storage materials. Among all the transition metals, titanium and its compounds show great catalytic effects on magnesium hydride. In this study, for the first time, TiO2 nanosheets with exposed {001} facets were synthesized and doped into MgH2. The TiO2 nanosheet (NS)-doped MgH2 showed superior kinetic performance and the lowest desorption temperature. The onset temperature of MgH2 + 5 wt% TiO2 NS for the release of hydrogen was 180.5 °C and the corresponding peak temperature was 220.4 °C, which are much lower than those of pure MgH2 and also distinctly lower than those of MgH2 + 5 wt% TiO2 nanoparticles (NP). For the isothermal dehydrogenation analysis, the MgH2 + 5 wt% TiO2 NS could release 6.0 wt% hydrogen within 3.2 min at 260 °C and desorb 5.8 wt% hydrogen within 6 min at 240 °C. It is worth noting that the MgH2 + 5 wt% TiO2 NS can even release 1.2 wt% hydrogen at a temperature as low as 180 °C within 300 min. The hydrogenation kinetics of MgH2 + 5 wt% TiO2 NS is also greatly improved, which could absorb hydrogen within only a few seconds at mild temperature. It can take up 3.3 wt% hydrogen at 50 °C and 5.4 wt% at 100 °C within 10 s. It is demonstrated that the tremendous enhancement in reaction kinetics of MgH2 can be ascribed to the nanometer size and highly active {001} facets of anatase TiO2. The higher average surface energy can significantly reduce the hydrogen desorption activation energy of MgH2 to 67.6 kJ mol−1, thus easily improving the hydrogen desorption properties.
研究领域:
材料科学
·
能源化学
✓ 已验证
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2025
·
IF 11.3
Jiacheng Ge,Xiaoyan Chen,Zhenqi Du,Yingying Zhou,Ruixin Qu,Jiangdong Cui,Shunke Ding,Wenhai Chu
Halogenated nitrophenols (HNPs) have raised significant concerns due to their extensive detection and potent toxicity. Understanding how these compounds persist and degrade over time is crucial for predicting their potential accumulation and assessing the long-term exposure risks. Kinetic studies showed that the degradation of HNPs through hydrolysis and chloramination over realistic hydraulic retention times is relatively low. The species-specific second-order rate constants for the reaction of hypochlorous acid and the acid-catalyzed reaction of hypochlorous acid with anionic HNP species, which accounted for HNP degradation during chlorination, range from 3.84 ± 1.09–363.25 ± 50.44 M⁻¹min⁻¹ and from (1.50 ± 0.091) × 10⁶ to (1.34 ± 0.36) × 10⁸ M⁻²min⁻¹ , respectively. The reactivity order of reactive species in hydrolysis, chlorination, and chloramination with HNP species has also been verified through computational modeling using density functional theory. The introduction of nitro group onto HNPs significantly diminishes the electron density of the benzene ring, thereby reducing their inherent reactivity compared with other aromatic DBPs. The hydrolysis and chlorination of HNPs primarily result in the formation of halogenated hydroquinones and various polyhaloquinones and polyhalophenols, respectively. These results suggest that HNPs and their transformation products exhibit relatively high persistence and exposure risks.
研究领域:
环境科学
·
饮用水安全
·
毒理学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Environmental Chemical Engineering
·
2024
·
IF 7.4
Kai He,Yuanfang Lai,Shuchen Wang,Jie Hong,Xianliang Huang
The application of sodium sulfide (Na 2 S) as sulfidation reagent of zero valent iron (ZVI) has been well studied, however, the effect of Na 2 S existence on ZVI reactivity remains obscure. In this study, Ni(II) removal performance, mechanism, and stability by ZVI with Na 2 S were investigated at neutral condition. The results showed that Ni(II) removal sharply increased from < 5–100% by ZVI within 60 min with the increase of Na 2 S concentration, but the subsequent Ni(II) release occurred. In addition to the slight Ni(II) removal by Na 2 S in aqueous phase , Ni(II) was mainly removed by the adsorption and reduction by Na 2 S mediated ZVI system. Characterization analysis indicated that Na 2 S could lead to the severe Fe 0 corrosion and the main corrosion product on ZVI was lepidocrocite , which played the dominant role for Ni(II) immobilization. Meanwhile, the formation of iron sulfides on ZVI surface would enhance Ni(II) reduction and partially transform the adsorbed Ni(II) to NiS. Moreover, the higher ionic strength could further enhance the initial Ni(II) removal rate but the stability became poor. Regardless of the additive methods , the Ni(II) removal significantly enhanced in the system of ZVI and Na 2 S combination. Overall, this work reveals the sulfide mediated Fe 0 corrosion and provides a potential method for enhancing the reactivity of ZVI in the treatment of Ni(II) pollution.
研究领域:
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）