{"title":"不同阴离子的 SO3H 功能化离子液体催化间二甲苯硝化反应的选择性和危害性研究:实验和理论方法","authors":"","doi":"10.1016/j.molliq.2024.126045","DOIUrl":null,"url":null,"abstract":"<div><p>Five imidazole based SO<sub>3</sub>H-functionalized ionic liquids (SFILs) with different anions were selected as catalysts to achieve efficient m-xylene nitration. The acidity and thermal stability of the ILs were characterized by UV–vis and thermogravimetry. The reaction selectivity of the m-xylene nitration catalyzed by five ILs was compared. [MIMBs]HSO<sub>4</sub> had the best catalytic activity with the maximum yield of 98.1 %. The effect of ILs on the exothermic behavior of m-xylene nitration was explored by reaction calorimeter. The reaction enthalpy (Δ<em>H</em>) and adiabatic temperature rise (Δ<em>T</em><sub>ad</sub>) were calculated to evaluate process hazards. The reaction order for the decomposition of different nitration products under adiabatic conditions was essentially close to 1. The process risk level for m-xylene nitration with the introduction of selected ILs was essentially downgraded from conditionally acceptable to acceptable, and the criticality was reduced from class 3 to 1. Furthermore, the acidic active sites of the ILs were predicted by the electrostatic potential. The solubility of m-xylene in the IL was investigated through the calculation of interaction energy. The roles of ILs as solvents and catalysts in nitration were resolved by density functional theory calculations. These findings could contribute to the understanding of the effect of ILs in modulating the process hazards and improving the selectivity of m-xylene nitration, and provide theoretical guidance for elucidating the catalytic mechanism of ILs in nitration.</p></div>","PeriodicalId":371,"journal":{"name":"Journal of Molecular Liquids","volume":null,"pages":null},"PeriodicalIF":5.3000,"publicationDate":"2024-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Study on the reaction selectivity and hazard of m-xylene nitration catalyzed by SO3H-functionalized ionic liquids with different anions: Experimental and theoretical approaches\",\"authors\":\"\",\"doi\":\"10.1016/j.molliq.2024.126045\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><p>Five imidazole based SO<sub>3</sub>H-functionalized ionic liquids (SFILs) with different anions were selected as catalysts to achieve efficient m-xylene nitration. The acidity and thermal stability of the ILs were characterized by UV–vis and thermogravimetry. The reaction selectivity of the m-xylene nitration catalyzed by five ILs was compared. [MIMBs]HSO<sub>4</sub> had the best catalytic activity with the maximum yield of 98.1 %. The effect of ILs on the exothermic behavior of m-xylene nitration was explored by reaction calorimeter. The reaction enthalpy (Δ<em>H</em>) and adiabatic temperature rise (Δ<em>T</em><sub>ad</sub>) were calculated to evaluate process hazards. The reaction order for the decomposition of different nitration products under adiabatic conditions was essentially close to 1. The process risk level for m-xylene nitration with the introduction of selected ILs was essentially downgraded from conditionally acceptable to acceptable, and the criticality was reduced from class 3 to 1. Furthermore, the acidic active sites of the ILs were predicted by the electrostatic potential. The solubility of m-xylene in the IL was investigated through the calculation of interaction energy. The roles of ILs as solvents and catalysts in nitration were resolved by density functional theory calculations. These findings could contribute to the understanding of the effect of ILs in modulating the process hazards and improving the selectivity of m-xylene nitration, and provide theoretical guidance for elucidating the catalytic mechanism of ILs in nitration.</p></div>\",\"PeriodicalId\":371,\"journal\":{\"name\":\"Journal of Molecular Liquids\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":5.3000,\"publicationDate\":\"2024-09-16\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Journal of Molecular Liquids\",\"FirstCategoryId\":\"92\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S0167732224021044\",\"RegionNum\":2,\"RegionCategory\":\"化学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q2\",\"JCRName\":\"CHEMISTRY, PHYSICAL\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Molecular Liquids","FirstCategoryId":"92","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0167732224021044","RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"CHEMISTRY, PHYSICAL","Score":null,"Total":0}
引用次数: 0
摘要
研究人员选择了五种含有不同阴离子的咪唑基 SO3H 功能化离子液体(SFILs)作为催化剂,以实现间二甲苯的高效硝化。紫外-可见光分析法和热重分析法对这些离子液体的酸度和热稳定性进行了表征。比较了五种离子交换树脂催化间二甲苯硝化反应的选择性。[MIMBs]HSO4的催化活性最好,最高产率为98.1%。通过反应量热计探讨了间二甲苯硝化放热行为对 IL 的影响。计算了反应焓(ΔH)和绝热温升(ΔTad),以评估过程危险性。在绝热条件下,不同硝化产物分解的反应顺序基本接近于 1。引入选定的 IL 后,间二甲苯硝化的工艺风险等级基本上从有条件可接受降为可接受,临界度从 3 级降为 1 级。此外,IL 的酸性活性位点是通过静电位来预测的。通过计算相互作用能,研究了间二甲苯在 IL 中的溶解度。通过密度泛函理论计算,解决了离子交换树脂在硝化过程中作为溶剂和催化剂的作用问题。这些研究结果有助于理解ILs在调节间二甲苯硝化过程危害和提高选择性方面的作用,并为阐明ILs在硝化过程中的催化机理提供了理论指导。
Study on the reaction selectivity and hazard of m-xylene nitration catalyzed by SO3H-functionalized ionic liquids with different anions: Experimental and theoretical approaches
Five imidazole based SO3H-functionalized ionic liquids (SFILs) with different anions were selected as catalysts to achieve efficient m-xylene nitration. The acidity and thermal stability of the ILs were characterized by UV–vis and thermogravimetry. The reaction selectivity of the m-xylene nitration catalyzed by five ILs was compared. [MIMBs]HSO4 had the best catalytic activity with the maximum yield of 98.1 %. The effect of ILs on the exothermic behavior of m-xylene nitration was explored by reaction calorimeter. The reaction enthalpy (ΔH) and adiabatic temperature rise (ΔTad) were calculated to evaluate process hazards. The reaction order for the decomposition of different nitration products under adiabatic conditions was essentially close to 1. The process risk level for m-xylene nitration with the introduction of selected ILs was essentially downgraded from conditionally acceptable to acceptable, and the criticality was reduced from class 3 to 1. Furthermore, the acidic active sites of the ILs were predicted by the electrostatic potential. The solubility of m-xylene in the IL was investigated through the calculation of interaction energy. The roles of ILs as solvents and catalysts in nitration were resolved by density functional theory calculations. These findings could contribute to the understanding of the effect of ILs in modulating the process hazards and improving the selectivity of m-xylene nitration, and provide theoretical guidance for elucidating the catalytic mechanism of ILs in nitration.
期刊介绍:
The journal includes papers in the following areas:
– Simple organic liquids and mixtures
– Ionic liquids
– Surfactant solutions (including micelles and vesicles) and liquid interfaces
– Colloidal solutions and nanoparticles
– Thermotropic and lyotropic liquid crystals
– Ferrofluids
– Water, aqueous solutions and other hydrogen-bonded liquids
– Lubricants, polymer solutions and melts
– Molten metals and salts
– Phase transitions and critical phenomena in liquids and confined fluids
– Self assembly in complex liquids.– Biomolecules in solution
The emphasis is on the molecular (or microscopic) understanding of particular liquids or liquid systems, especially concerning structure, dynamics and intermolecular forces. The experimental techniques used may include:
– Conventional spectroscopy (mid-IR and far-IR, Raman, NMR, etc.)
– Non-linear optics and time resolved spectroscopy (psec, fsec, asec, ISRS, etc.)
– Light scattering (Rayleigh, Brillouin, PCS, etc.)
– Dielectric relaxation
– X-ray and neutron scattering and diffraction.
Experimental studies, computer simulations (MD or MC) and analytical theory will be considered for publication; papers just reporting experimental results that do not contribute to the understanding of the fundamentals of molecular and ionic liquids will not be accepted. Only papers of a non-routine nature and advancing the field will be considered for publication.