Research progress on preparation and purification of fluorine-containing chemicals in lithium-ion batteries

With the development of digital products,electric vehicles and energy storage technology,electronic chemicals play an increasingly prominent role in the field of new energy such as lithium-ion batteries.Electronic chemicals have attracted extensive attention in various fields.Characteristics of high-end electronic chemicals are high purity and low impurity content,which requires a very strict separation and purification process.At present,crystallization is a key technology for their separation and purification of electronic chemicals.In this work,the representative fluorine-containing compounds in cathode and anode materials,separator and electrolyte of lithium-ion batteries are introduced.The latest technologies for the preparation and purification of four kinds of fluorine-containing battery chemicals by crystallization technology are reviewed.In addition,the research prospects and suggestions are put forward for the separation of fluorine-containing battery chemicals.

Heterogeneous catalysis under flow for the 21st century fine chemical industry

Due to metal leaching and poor catalyst stability, the chemical industry's fine chemical and pharmaceutical sectors have been historically reluctant to use supported transition metal catalysts to manufacture fine chemicals and active pharmaceutical ingredients. With the advent of new generation supported metal catalysts and flow chemistry, we argue in this study, this situation is poised to quickly change. Alongside heterogenized metal nanoparticles, both single-site molecular and single-atom catalyst will become ubiquitous. This study offers a critical outlook taking into account both technical and economic aspects.

Concentration Characteristics and Sources of Chemical Elements in Atmospheric Fine Particles (PM_(2.5)) in Autumn in Xi'an City

[Objective] The aim was to study the concentration characteristics and sources of chemical elements in atmospheric fine particles (PM2.5) in autumn in Xi’an City. [Method] By means of mini-volume sampler, PM2.5 samples in atmosphere in Xi’an were collected in October 2009, and the concentration characteristics and sources of elements in PM2.5 were analyzed. [Result] The average mass concentration of PM2.5 in atmosphere in autumn in Xi’an City was 168.44 μg/m3 which was higher than that of Beijing and Pearl River Delta area, and the minimum and maximum value were 53.29 and 358.16 μg/m3, respectively. The mass concentration of S, Zn, K, Cl, Ca and Fe in PM2.5 was above 1.0 μg/m3, being at high pollution level. In addition, K had obvious correlation with organic carbon (OC) and element carbon (EC), with the correlation coefficients of 0.76 and 0.75 (P<0.000 1), respectively, and it showed that OC and EC had the same source as K, namely biomass burning had certain contribution to OC and EC. Enrichment factors analysis revealed that K, Ca, Fe, Ti, Mn and Cr mainly came from earth crust, rock weathering and other natural sources, while anthropogenic pollution sources had great effects on S, Zn, Cl, Pb, Br, Mo, Cd and As which were affected by soil dust and other natural sources slightly, and Cd had the highest enrichment factor and mainly came from metal smelting. In a word, coal combustion, biomass burning, vehicle emissions, metallurgical, chemical industry and dust were the main sources of PM2.5 in autumn in Xi’an. [Conclusion] The study could provide theoretical foundation for the control of urban environmental pollution.

Tendencies of research and development in resources chemicals and materials -Summarization of a Youth’s topic forum

The 2022′s Youth Forum on Resources Chemicals and Materials was held on November 12-13,2022,in Shenyang,Liaoning Province.Panel discussions focus on the cutting-edge researches on“Fine chemicals and advanced alloy materials”and“Utilization of fossil and renewable carbon resources”.This perspective summarizes the major di-rections of scientific research and technical developments aligned in the discussions.Fine chemical industry tends to pursue green and low-carbon products,intelligent product design,and start manufacturing.In recent years,great efforts have been made for transformation of cellulose into advanced electronic as well as life-service bio-materials and to the high-selectivity extraction of bio-base aromatic chemicals from lignin.Concerning high-end alloy materials,regulating deformation mechanism of crystal to construct bimodal microstructure seems highly prospective in harmonizing precipitate hardening effect and plastic deformation capacity.As we know,utiliza-tion of fossil carbon resources constitutes the major anthropogenic carbon emissions,and the related innovations thus should be,for possibly a long period,on increasing energy production efficiency and low-carbon cascaded conversion of fossil fuels,especially of coal.

韩国FINE CHEMICAL CO．，LTD在静观其变中掌握主动！

近日，中国聚氨酯网走访了韩国FINE CHEMICAL CO．，LTD．(简称：KFC)的上海办事处，首席代表朴昌瑞先生热忱地接受了记者的采访。这家临时办事处位于上海虹桥，今年2月刚刚成立，是KFC在中国进行本土化经营的起点。

Technical Challenges and Progress in Fluidized Bed Chemical Vapor Deposition of Polysilicon

Various methods for production of polysilicon have been proposed for lowering the production cost andenergy consumption, and enhancing productivity, which are critical for industrial applications. The fluidized bed chemical vapor deposition （FBCVD） method is a most promising alternative to conventional ones, but the homogeneous reaction of silane in FBCVD results in unwanted formation of fines, which will affect the product qualityand output. There are some other problems, such as heating degeneration due to undesired polysilicon deposition on the walls of the reactor and the heater. This article mainly reviews the technological development on FBCVD of polycrystalline silicon and the research status for solving the above problems. It also identifies a number of challenges to tackle and principles should be followed in the design ofa FBCVD reactor.

Intraspecific variations in fine root N and P and factors affecting their concentrations in Masson pine plantations across subtropical China

Fine roots(<2 mm)play vital roles in water and nutrient uptake.However,intraspecific variations in their chemical traits and their controlling mechanisms remain poorly understood at a regional scale.This study examined these intraspecific variations in fine roots in Masson pine(Pinus massoniana Lamb.)plantations across subtropical China and their responses to environmental factors.Root nitrogen(N)and phosphorus(P)concentrations and their mass ratios(N:P)ranged from 3.5 to 11.7 g kg^(-1),0.2 to0.9 g kg^(-1),and 7.8 to 51.6 g kg^(-1),respectively.These three chemical traits were significantly different between sites and in longitudinal patterns across subtropical China.Mean annual temperature was positively related to root N concentration but negatively related to root P concentration.There were significant,negative relationships between clay content and root P concentration and between pH and root N concentration.Available N had no significant relationship with root N concentration,while available P was a significantly positive relationship with root P concentration.The combined effects of altitude,climate(temperature and precipitation)and soil properties(pH,clay content,available N and P)explained 26%and 36%of the root N and P concentrations variations,respectively.These environmental variables had direct and indirect effects and exhibited disproportionate levels of total effects on root N and P concentrations.Root N and P concentrations explained 35%and 65%variations in their mass ratios,respectively.The results highlight different spatial patterns of chemical traits and various environmental controls on root N and P concentrations in these ecosystems.More cause-effect relationships of root chemical traits with abiotic and biotic factors are needed to understand nutrient uptake strategies and the mechanisms controlling intraspecific variations in plant traits.

Chemical Composition of Summertime PM_(2.5) and Its Relationship to Aerosol Optical Properties in Guangzhou,China

Urban aerosols have a large effect on the deterioration of air quality and the degradation of atmospheric visibility.Characterization of the chemical composition of PM 2.5 and in situ measurements of the optical properties of aerosols were conducted in July 2008 at an urban site in Guangzhou,Southern China.The mean PM 2.5 concentration for the entire period was 53.7±23.2 μg m 3.The mean PM 2.5 concentration (82.7±25.4 μg m 3) on hazy days was roughly two times higher than that on clear days (38.8±8.7 μg m 3).The total water-soluble ion species and the total average carbon accounted for 47.9%±4.3% and 35.2%±4.5%,respectively,of the major components of PM 2.5.The increase of secondary and carbonaceous aerosols,in particular ammonium sulfate,played an important role in the formation of haze pollution.The mean absorption and scattering coefficients and the single scattering albedo over the whole period were 53±20 M m 1,226±111 M m 1,and 0.80±0.04,respectively.PM 2.5 had a high linear correlation with the aerosol extinction coefficient,elemental carbon (EC) was correlated with aerosol absorption,and organic carbon (OC) and SO 4 2 were tightly linked to aerosol scattering.

合成气乙二醇产品质量提升技术综述

总结合成气制乙二醇产品质量提升的4种技术手段:液相加氢,精馏加碱,产品塔釜加药剂和离子交换树脂吸附,分析4种方法的作用原理和效果,提出产品质量提升的根本在于加氢催化剂性能的提高,液相加氢需进一步提高催化剂活性,从而简化生产工艺。综述对乙二醇生产具有一定的借鉴作用。

高校化学实验室精细化管理探析

随着高校化学实验室的不断发展,实验室管理的重要性也体现得愈加明显。精细化管理是实验室管理的一种重要方式,它可以提高实验室的效率和安全性,保证实验室安全、高效地运转。结合化学实验教学的特点和我校教学实际,我们提出了强化实验教学的精细化与全过程管理的理念。本文将从实验室管理的现状、精细化管理的必要性、精细化管理的实施和精细化管理的效果等方面进行探讨。精细化管理重在解决怎样管、管什么和谁来管的问题,通过实施实验室精细化管理将有助于提升实验室管理的效益,进一步助推创新型人才的培养。

《精细化工与生活》通识教育选修课中的教学模式探索

结合自身教学和实践,分析了新疆大学《精细化工与生活》通识教育选修课教学中存在的现状问题,提出了改善课程教学理念、加强课程的规范化管理、优化课程的教学内容及方法、改革课程的教学考核方式措施,为系列通识教育选修课的课程建设提供有效的新方法与新思路。

精细化工园污水处理厂工程设计

我国目前水资源紧张,水污染问题日益严重,尤其是化工企业存在污水排放不达标等问题。为此,针对精细化工园区的污水处理厂,工程服务范围主要是某县产业集聚区。根据相关资料,确定污水处理厂的设计规模、设计进出水水质、污水处理工艺方案。通过实证研究发现,该工程建成后能够有效改善水环境,降低对地方水系的污染,减少污染物的排放,对提高地方投资环境、促进经济增长有积极的意义。

应用型人才培养视角下精细化学品化学课程教学改革探索

精细化学品化学是应用化学专业的一门专业核心课程.在理论课程每章节前,需引入与本章节相关联的当前国内外研究热点和市场企业生产情况,同时融入具体生产案例,并开展与理论课程相对应的实验课程.实验课程前期需进行企业调研,优化实验教学内容,主要途径包括:将最新科研成果引入实验教学中,注重实验技能训练,同时将教学内容与企业见习实践密切结合.这些有效措施有助于学生对课程知识的深入学习,拓宽学生的知识面,培养学生创新和环境友好意识,提高学生综合运用知识的能力,增强学生的实践能力,提升学生的就业从业竞争力.

催化剂酸碱性与催化酯醛缩合性能的关系

以γ-Al_(2)O_(3)和SiO_(2)为载体,采用浸渍法引入不同含量Na^(+)、K^(+)和Cs+碱金属离子,制备了一系列酯醛气相缩合催化剂。利用XRD、BET、NH3-TPD和CO_(2)-TPD对催化剂的结构和表面酸、碱性进行了表征,并以丙酸甲酯与甲醛为原料,考察了其催化酯醛气相缩合反应性能。结果表明,在0.2 MPa、370℃和质量空速为1.2 h^(-1)的条件下,以10%(以载体SiO_(2)质量为基准,下同)Cs/SiO_(2)为催化剂时,丙酸甲酯转化率最高(41.03%),甲基丙烯酸甲酯选择性为99.20%。在有丰富碱活性中心的前提下,催化剂表面弱碱性位点含量与其催化酯醛气相缩合反应性能呈正相关关系,催化剂表面酸性位点和中强碱性位点的存在会导致催化剂催化活性和选择性的降低。

Q[6]-PW_(12)自组装体制备及其催化合成乙酸乙酯

以六元瓜环(Q[6])及Keggin型磷钨酸(PW_(12))为原料,制备Q[6]-PW_(12)自组装体。将Q[6]-PW_(12)自组装体作为催化剂应用于乙酸与乙醇酯化反应合成乙酸乙酯。结果表明,Q[6]与PW_(12)发生了自组装作用,且Q[6]-PW_(12)自组装体具有多孔结构特征;Q[6]-PW_(12)自组装体对酯化反应合成乙酸乙酯具有催化作用,且自组装体催化剂经过多次循环使用后依然效果良好。

Carbon Monoxide as C1 Building Block in Fine Chemical Synthesis

Carbon monoxide(CO)has become one of the most relevant and versatile renewable C1 building blocks for chemical synthesis,especially in the fine chemicals industry,due to the development of efficient and selective catalysts for its activation.In this review,we present a comprehensive critical analysis of the last 10 years literature on the use of CO as a renewable feedstock for fine chemicals production.The review is organized by type of catalytic reaction,namely alkene and alkyne carbonylation,hydroformylation,carbonylation of aryl halides,carbonylative cross-coupling and C-H carbonylation.Notable examples of the synthesis of relevant building blocks and/or known pharmaceuticals are highlighted.Emphasis is placed on examples of utilizing CO as the C1 building block in one or more catalytic steps.The catalyst used and the reaction conditions are consistently presented throughout all of the examples.

羟乙基乙二胺的连续流制备工艺

以乙二胺和环氧乙烷为原料,在具有特殊微结构的连续流微反应器内发生乙氧基化反应合成羟乙基乙二胺。考察了原料物质的量比、乙二胺含水量、反应温度、停留时间对反应的影响。结果表明,在n(乙二胺)∶n(环氧乙烷)=3∶1、乙二胺含水量为0.96%(质量分数)、反应温度为80℃、停留时间为60 s的最佳工艺条件下,环氧乙烷转化率接近100%,羟乙基乙二胺的选择性为87.4%,二羟乙基乙二胺的选择性为9.2%。间歇釜式反应工艺在相同物料比和反应温度条件下,羟乙基乙二胺的选择性为83.5%,二羟乙基乙二胺的选择性为15.9%。连续流微反应器能有效提高羟乙基乙二胺的选择性,降低副反应的发生,同时大大缩短了反应时间,提高了反应效率。

封育年限对武夷山毛竹细根功能性状的影响

自然封育是培育森林资源重要且有效的途径,细根作为植物体重要的资源获取型器官,在森林群落发挥生态功能中扮演重要角色。为明晰自然封育对毛竹细根功能性状的影响,采用空间代替时间的研究方法,以武夷山国家公园内正常经营和封育年限为3、5、10、15年和40年的毛竹林作为研究对象,揭示不同封育年限下毛竹细根功能性状的差异以及对土壤理化性质变化的适应规律。结果表明:(1)封育年限对毛竹细根的功能性状具有显著影响。随着封育年限的增长,毛竹细根的比根长、比根面积、全碳、全氮和全磷含量均呈现先上升后下降的变化趋势,组织密度、碳氮比和碳磷比呈现先下降后上升的趋势,同其他封育毛竹林群落相比,封育10和15年的毛竹林群落中细根比根长、比根面积和养分含量得到显著提高。土壤层次和细根径级对细根功能性状同样具有显著影响。(2)毛竹细根功能性状间随封育年限的变化存在显著的相关性。比根长、比根面积、全碳含量、全氮含量和全磷含量彼此之间存在显著的正相关关系,与碳氮比、碳磷比和组织密度存在显著的负相关关系。(3)随着封育演替进程,毛竹林群落中土壤因子的变化驱动着细根功能性状发生改变,土壤容重同细根养分含量呈显著的负相关关系,土壤碳磷含量与细根比根长和比根面积存在显著的正相关关系,土壤养分含量与细根养分含量呈现极显著正相关关系。综上,自然封育促使毛竹细根通过自身表型可塑性合理权衡不同功能性状之间的资源配置,当封育10—15年,毛竹细根将更多养分集中于资源获取型性状的构建,吸收能力和效率显著提高,林分生产力和生态功能较优,在封育10—15年后适当进行科学的人为经营活动有助于毛竹林的可持续健康发展。

环烯烃开环易位聚合物的合成

采用MoCl_(5)为核心的齐格勒-纳塔催化剂合成降冰片烯-四环十二烯的开环易位聚合物,实现稳定的100%单体转化率,凝胶率0%。并采用Al_(2)O_(3)负载的Ru催化剂和SiO 2/Al_(2)O_(3)负载的Ni金属催化剂对相同的降冰片烯-四环十二烯开环易位聚合物进行非均相加氢,可实现100%的加氢率,且简单过滤即可将催化剂与聚合物溶液完全分离。两种加氢催化剂的产品具有不同的性质,Ni负载催化剂最佳反应条件:催化剂含量10%、反应温度190℃、初始氢气压力4 MPa、反应时间2 h,加氢产物的熔融指数76 g·min^(-1),玻璃化转变温度126℃;Ru负载催化剂最佳反应条件:催化剂含量2%、反应温度180℃、初始氢气压力4 MPa、反应时间2 h,加氢产物的熔融指数10 g·min^(-1),玻璃化转变温度131℃。

紫金山3种优势乔木细根功能性状的序级变化特征

【目的】明晰紫金山3种优势乔木细根功能性状在序级间的变化特征,为深入理解不同根序细根在地下生理生态过程中的作用提供理论依据。【方法】以紫金山3种优势乔木糙叶树、朴树和枫香为对象,采用随机区组设计设置3个20 m×20 m的样方,采集优势树种的细根,分析不同树种细根直径、比根长、比表面积、根组织密度、C、N及P含量等功能性状随序级的变化特征。【结果】1)树种对细根形态性状和化学性状都有显著影响,而序级只对细根直径、比根长、比表面积、细根N、P含量和C/N有显著影响。2)随着序级升高,3种优势乔木的细根直径和C/N呈现增加趋势,比根长、比表面积、N含量和P含量整体呈现减小趋势,根组织密度和C含量随序级增加没有明显的变化规律。3)在1~5级根中,朴树的直径最小,比根长和比表面积最大;糙叶树的根组织密度最大;朴树的C含量最高;枫香的C/N最小。在1级根中,糙叶树的N含量最高,朴树的P含量最高。糙叶树和枫香的细根生物量随着序级升高而增加,朴树的1级根生物量大于2、3级根生物量。4)主成分分析表明,3种优势乔木的细根功能性状分为两个变异维度,糙叶树偏向于资源获取型,朴树偏向于自主觅食资源获取型,而枫香偏向于不同策略的权衡。【结论】细根功能性状和多维度根系策略在树种之间存在差异,表明糙叶树和朴树细根对养分的获取效率较高,枫香细根养分获取效率较低;但枫香细根的分解速率可能快于糙叶树和朴树。