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1.
纵观以往化纤单体生产的革新化措施和绿色化进程,大致可分成3个层面:(1)优化工艺,减少跑冒滴漏;(2)改变反应方式或引入新催化剂;(3)彻底改变原料路线.前两个层面的革新多数能达到节能、降耗、降低生产成本的效果,已取得了较多工业化成果.丁二烯或生物质等原料路线试图从第3个层面解决问题,绿色化虽彻底,但或因引入新的有害物质,或因副产物多,目的产物收率太低,物耗和能耗尚难与传统的芳烃原料路线媲美,工业化道路更艰难.为了推进化纤单体生产的绿色化进程,尽早发现新的切入点,找准绿色化方向,本文综述了前人的绿色化成果,试图从原料路线、制备工艺和"三废"处理3个方面追寻"领跑者"的足迹.针对已有工艺的物耗、能耗和生产成本分析比较以及取舍绿色化革新措施时,常因比较边界(范围)不一致,得出偏颇的观点,误导读者,建议先导入原子经济性(质量效率)评价和全生命周期清单分析等过渡指标,再建立更完善的评价体系,逐步达到严格的全生命周期评价、多维评价的水平.  相似文献   

2.
This critical review provides a survey illustrated by recent references of different strategies to achieve a sustainable conversion of biomass to bioproducts. Because of the huge number of chemical products that can be potentially manufactured, a selection of starting materials and targeted chemicals has been done. Also, thermochemical conversion processes such as biomass pyrolysis or gasification as well as the synthesis of biofuels were not considered. The synthesis of chemicals by conversion of platform molecules obtained by depolymerisation and fermentation of biopolymers is presently the most widely envisioned approach. Successful catalytic conversion of these building blocks into intermediates, specialties and fine chemicals will be examined. However, the platform molecule value chain is in competition with well-optimised, cost-effective synthesis routes from fossil resources to produce chemicals that have already a market. The literature covering alternative value chains whereby biopolymers are converted in one or few steps to functional materials will be analysed. This approach which does not require the use of isolated, pure chemicals is well adapted to produce high tonnage products, such as paper additives, paints, resins, foams, surfactants, lubricants, and plasticisers. Another objective of the review was to examine critically the green character of conversion processes because using renewables as raw materials does not exempt from abiding by green chemistry principles (368 references).  相似文献   

3.
Green Chemistry and Modern Technology   总被引:4,自引:0,他引:4  
The basic principles, approaches, and early achievements of green chemistry are considered. The definition of green chemistry as a branch of chemistry that studies the laws of passing of chemical reactions and the properties of substances participating in such reactions, with the aim of acquiring basic knowledge that provides a basis for designing chemical technologies that eliminate (sharply curtail) the use and production of materials that pose a risk to the environment.  相似文献   

4.
Photocatalytic hydrogen evolution is viewed as a promising green strategy to utilize the inexhaustible solar energy and provide clean hydrogen fuels with zero‐emission characteristic. The nature of semiconductor‐based photocatalysts is the key point to achieve efficient photocatalytic hydrogen evolution. Conjugated materials have been recently emerging as a novel class of photocatalysts for hydrogen evolution and photocatalytic reactions due to their electronic properties can be well controlled via tailor‐made chemical structures. Hydrophilic conjugated materials, a subgroup of conjugated materials, possess multiple advantages for photocatalytic applications, thus spurring remarkable progress on both material realm and photocatalytic applications. This minireview aims to provide a brief review of the recent developments of hydrophilic conjugated polymers/small molecules for photocatalytic applications, and special concern on the rational molecular design and their impact on photocatalytic performance will be reviewed. Perspectives on the hydrophilic conjugated materials and challenges to their applications in the photocatalytic field are also presented.  相似文献   

5.
石墨烯基纤维电容器的可控制备及应用   总被引:1,自引:1,他引:0  
聂肖威  陈南  李静  曲良体 《应用化学》2016,33(11):1234-1244
超级电容器又名电化学电容器,是一种绿色储能器件。 超级电容器的研究,从根本上讲是寻找比表面积大且可以被充分利用的电极材料。 石墨烯作为sp2杂化碳质材料的基元单位,具有独特的二维结构和优异的物化特性,使得其在超级电容器领域具有巨大的应用潜力,其中石墨烯纤维超级电容器受到了研究工作者越来越广泛的关注。 本文通过对一维石墨烯纤维的自组装以及与制备材料的共组装来作为超级电容器的电极材料,对其可控制备进行了系统的归纳和总结,可控构建独特的电极材料,使其性能得以优化,组装出高性能的超级电容器,并对相关领域的发展趋势做了展望。  相似文献   

6.
木塑复合材料改性研究进展   总被引:4,自引:0,他引:4  
木塑复合材料不仅具有原木特有的木质感,而且尺寸稳定性好,耐水性、耐磨性、耐化学腐蚀性优良,不怕虫蛀,易于着色,维护要求低,使用寿命长,易于成型,可二次加工等众多优异性能,是21世纪重点开发的绿色环保新型材料之一。本文介绍了国内外木塑复合材料的应用与研究进展,阐述了木塑复合材料研究开发的关键问题。针对目前国内外木塑复合材料的物理改性、化学改性以及复合改性方法进行了综述,对木塑复合材料的发展方向进行了展望。  相似文献   

7.
In this era of molecular biology, protein crystallization is often considered to be a necessary first step in obtaining structural information through X‐ray diffraction analysis. In a different light, protein crystals can also be thought of as materials, whose chemical and physical properties make them broadly attractive and useful across a larger spectrum of disciplines. The full potential of these protein crystalline materials has been severely restricted in practice, however, both by their inherent fragility, and by strongly held skepticism concerning their routine and predictable growth, formulation, and practical application. Fortunately, these problems have turned out to be solvable. A systematic exploration of the biophysics and biochemistry of protein crystallization has shown that one can dependably create new protein crystalline materials more or less at will. In turn, these crystals can be readily strengthened, both chemically and mechanically, to make them suitable for practical commercialization. Today, these novel materials are used as industrial catalysts on a commercial scale, in bioremediation and “green chemistry” applications, and in enantioselective chromatography of pharmaceuticals and fine chemicals. In the near future, their utility will expand, to include the purification of protein drugs, formulation of direct protein therapeutics, and development of adjuvant‐less vaccines.  相似文献   

8.
Carbon dioxide (CO2) sequestration, storage and recycling will greatly benefit from comprehensive studies of physical and chemical gas–liquid processes involving CO2. Over the past five years, microfluidics emerged as a valuable tool in CO2‐related research, due to superior mass and heat transfer, reduced axial dispersion, well‐defined gas–liquid interfacial areas and the ability to vary reagent concentrations in a high‐throughput manner. This Minireview highlights recent progress in microfluidic studies of CO2‐related processes, including dissolution of CO2 in physical solvents, CO2 reactions, the utilization of CO2 in materials science, and the use of supercritical CO2 as a “green” solvent.  相似文献   

9.
This paper aims to connect philosophy of chemistry, green chemistry, and moral philosophy. We first characterize chemistry by underlining how chemists: (1) co-define chemical bodies, operations, and transformations; (2) always refer to active and context-sensitive bodies to explain the reactions under study; and (3) develop strategies that require and intertwine with a molecular whole, its parts, and the surroundings at the same time within an explanation. We will then point out how green chemists are transforming their current activities in order to act upon the world without jeopardizing life. This part will allow us to highlight that green chemistry follows the three aforementioned characteristics while including the world as a partner, as well as biodegradability and sustainability concerns, into chemical practices. In the third part of this paper, we will show how moral philosophy can help green chemists: (1) identify the consequentialist assumptions that ground their reasoning; and (2) widen the scope of their ethical considerations by integrating the notion of care and that of vulnerability into their arguments. In the fourth part of the paper, we will emphasize how, in return, this investigation could help philosophers querying consequentialism as soon as the consequences of chemical activities over the world are taken into account. Furthermore, we will point out how the philosophy of chemistry provides philosophers with new arguments concerning the key debate about the ‘intrinsic value’ of life, ecosystems and the Earth, in environmental ethics. To conclude, we will highlight how mesology, that is to say the study of ‘milieux’, and the concept of ‘ecumeme’ proposed by the philosopher and geographer Augustin Berque, could become important both for green chemists and moral philosophers in order to investigate our relationships with the Earth.  相似文献   

10.
11.
It is challenging work to develop a low-cost, efficient, and environmentally friendly Cr(VI) adsorbent for waste water treatment. In this paper, we used hemicelluloses from chemical fiber factory waste as the raw material, and prepared two kinds of carbon materials by the green hydrothermal method as adsorbent for Cr(VI). The results showed that hemicelluloses hydrothermally treated with citric acid (HTC) presented spherical shapes, and hemicelluloses hydrothermally treated with ammonia solution (HTC-NH2) provided spongy structures. The adsorption capacity of the samples can be obtained by the Langmuir model, and the adsorption kinetics could be described by the pseudo-second-order model at pH 1.0. The maximum adsorption capacity of HTC-NH2 in the Langmuir model is 74.60 mg/g, much higher than that of HTC (61.25 mg/g). The green hydrothermal treatment of biomass with ammonia solution will provide a simple and feasible way to prepare adsorbent for Cr(VI) in waste water treatment.  相似文献   

12.
Chemistry made once expensive leisure activities available to public by providing inexpensive materials for fishing rods, golf equipment etc. Nowadays, eco-minded costumers wish the impact of their leisure activities on environment as little as possible, and thus expect materials to be overall sustainable. Particularly, the hospitality sector has to fulfill the expectations of eco-minded tourists who prefer hotels engaged in activities for protecting natural resources and working against waste accumulation. The recent developments in green chemistry and material design can contribute to the sustainability of leisure industry. In this short review research outcomes regarding the development of materials which can be formed, degraded and reformed into new materials are presented. Finally, a business model called “material leasing” based on the principles of “chemical leasing” for the implementation of new materials in the hospitality and leisure sectors is proposed.  相似文献   

13.
Summary: Polymers that have one of the three complementary colors (red, green, and blue, RGB) in the neutral state and high transmissivity in the oxidized state are the key materials towards use in electrochromic devices and displays. Although many neutral state red and blue polymers have been reported up to date, green polymers with highly transmissive oxidized states, high optical contrasts, fast switching times, and advanced long-term switching stabilities were essentially missing in the literature. This paper reviews our previous efforts towards realization of neutral state green polymers with highly transmissive oxidized state. The key to this problem was found to be the synthesis of donor-acceptor polymers bearing benzothiadiazole or quinoxaline derivatives as the acceptor and electron rich 3,4-ethylenedioxythiophene unit as the donor component. Green neutral state polymeric materials with highly transmissive oxidized state with excellent electrochromic properties have been realized with the design and synthesis of these types of materials. A solution processable green polymeric material has also been realized via chemical polymerization that has shown all superior properties of the electrochemically synthesized counterparts.  相似文献   

14.
利用根霉菌发酵生产富马酸*   总被引:1,自引:0,他引:1  
高振  张昆  黄和  李霜  韦萍 《化学进展》2009,21(1):251-264
富马酸是一种重要的平台化合物和精细化学品,广泛应用于材料、医药、食品及饲料添加剂等领域,市场潜力巨大。利用可再生生物质为原料发酵生产富马酸符合当前社会对绿色环保、健康安全及可持续发展的总体需求。本文对发酵生产富马酸的常见根霉菌及其代谢机理进行了评述,并详细讨论了营养成分、菌体形态、pH控制及产物分离回收技术等对富马酸生产强度和生产成本的影响。随着科技的不断发展,应用各种新兴手段不断改良现有菌种及工艺,必将实现发酵法生产富马酸的大规模工业化。  相似文献   

15.
Summary A restorer's questions on chemical analysis of paint binders to support his complicated work has always had an exceptional appeal for chemists. Non-destructive surface analysis of rather complex materials such as paint binders is possible. The advantages of vibrational spectroscopy related to the details about chemical structure of organic compounds have been combined with sophisticated methods of multivariate data analysis. Reflectance spectra of several paint binders on ground chalk were measured using a fast, sensitive FTIR spectrometer equipped with an infrared microscope. The initial reflectance spectra include sufficient structural information to allow successful classification by hierarchical cluster analysis (HCA). Similarities between the several binders are plotted as dendrograms which are well structured. Their explanation will be discussed in detail. Finally the postulated feature sets will be checked up by principal component analysis (PCA) as to their relevance and information content.  相似文献   

16.
The increasing environmental concern and promotion of “green processes” are forcing the substitution of traditional acid and base homogeneous catalysts by solid ones. Among these heterogeneous catalysts, zeolites and zeotypes can be considered as real “green” catalysts, due to their benign nature from an environmental point of view. The importance of these inorganic molecular sieves within the field of heterogeneous catalysis relies not only on their microporous structure and the related shape selectivity, but also on the flexibility of their chemical composition. Modification of the zeolite framework composition results in materials with acidic, basic or redox properties, whereas multifunctional catalysts can be obtained by introducing metals by ion exchange or impregnation procedures, that can catalyze hydrogenation–dehydrogenation reactions, and the number of commercial applications of zeolite based catalysts is continuously expanding.In this review we discuss determinant issues for the development of zeolite based catalysts, going from zeolite catalyst preparation up to their industrial application. Concerning the synthesis of microporous materials we present some of the new trends moving into larger pore structures or into organic free synthesis media procedures, thanks to the incorporation of novel organic templates or alternative framework elements, and to the use of high-throughput synthesis methods. Post-synthesis zeolite modification and final catalyst conformation for industrial use are briefly discussed.In a last section we give a thorough overview on the application of zeolites in industrial processes. Some of them are well established mature technologies, such as fluid catalytic cracking, hydrocracking or aromatics alkylation. Although the number of zeolite structures commercially used as heterogeneous catalysts in these fields is limited, the development of new catalysts is a continuous challenge due to the need for processing heavier feeds or for increasing the quality of the products. The application of zeolite based catalysts in the production of chemicals and fine chemicals is an emerging field, and will greatly depend on the discovery of new or known structures by alternative, lower cost, synthesis routes, and the fine tuning of their textural properties. Finally, biomass conversion and selective catalytic reduction for conversion of NOx are two active research fields, highlighting the interest in these potential industrial applications.  相似文献   

17.
Nanostructured and nanosized materials are widely applied to tackle the pressing challenges associated with energy conversion. In this conceptual review, rather than highlighting separate examples, we aim to give a general overview about where and how nanostructure design can be beneficial in the three major research fields(photo)thermal chemical energy conversion, electrochemical energy conversion, and solar energy conversion. It will be shown that in many cases the design of catalytically active nanostructures is the main task and that especially for catalysts nanostructure and activity are inseparably linked to each other. Moreover, electrochemical and photochemical processes are complicated by the overlap of multiple processes that all need to be optimized, including in particular light absorption, charge migration,recombination and trapping events and surface processes. It will also be shown how the development of materials for new challenges can often be based on our knowledge on existing materials for related applications.  相似文献   

18.
Layered materials are of high importance because of their anisotropy and as a source of 2D materials. Whilst there is a plethora of multi‐elemental 2D materials, the number mono‐elemental 2D materials is rather limited. Herein, we demonstrate that aqueous shear exfoliation can be used to obtain As, Sb, and Bi exfoliated nanosheets. Morphological and chemical characterization of the exfoliated materials shows a decrease in thickness, sheet‐to‐nanosheet scale, and partial oxidation owing to a higher surface area. The electrochemical performance is tested in terms of inherent electrochemistry, electron transfer, and sensing applications as demonstrated with ascorbic acid. Potential energy‐related applications are evaluated in the hydrogen evolution reaction (HER), oxygen evolution reaction (OER), and oxygen reduction reaction (ORR), with shear‐exfoliated Sb having the best electrochemical performance overall. These findings will have a profound impact on the preparation and application of 2D mono‐elemental materials.  相似文献   

19.
以"碳的结构与性能及其应用"为例说明元素化学课堂教学中的方法,引导学生在复习碳元素的结构与性质的基础上,组织学生开展课堂讨论,引导学生对不断涌现的新型碳材料的关注和兴趣。同时,分组讨论碳氧化物的结构与化学性质之间关系及其有效利用,即模拟光合作用实现CO2的光催化还原和基于费托合成实现CO为原料制备燃料,鼓励和推进学生开展碳材料及其应用的本科生科研训练,实现课堂知识与科学研究衔接。  相似文献   

20.
Layered materials are of high importance because of their anisotropy and as a source of 2D materials. Whilst there is a plethora of multi‐elemental 2D materials, the number mono‐elemental 2D materials is rather limited. Herein, we demonstrate that aqueous shear exfoliation can be used to obtain As, Sb, and Bi exfoliated nanosheets. Morphological and chemical characterization of the exfoliated materials shows a decrease in thickness, sheet‐to‐nanosheet scale, and partial oxidation owing to a higher surface area. The electrochemical performance is tested in terms of inherent electrochemistry, electron transfer, and sensing applications as demonstrated with ascorbic acid. Potential energy‐related applications are evaluated in the hydrogen evolution reaction (HER), oxygen evolution reaction (OER), and oxygen reduction reaction (ORR), with shear‐exfoliated Sb having the best electrochemical performance overall. These findings will have a profound impact on the preparation and application of 2D mono‐elemental materials.  相似文献   

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