1、.Unit 1 Chemical Industry化学工业1.Origins of the Chemical Industry Although the use of chemicals dates back to the ancient civilizations, the evolution of what we know as the modern chemical industry started much more recently. It may be considered to have begun during the Industrial Revolution, about
2、1800, and developed to provide chemicals roe use by other industries. Examples are alkali for soapmaking, bleaching powder for cotton, and silica and sodium carbonate for glassmaking. It will be noted that these are all inorganic chemicals. The organic chemicals industry started in the 1860s with th
3、e exploitation of William Henry Perkins discovery if the first synthetic dyestuffmauve. At the start of the twentieth century the emphasis on research on the applied aspects of chemistry in Germany had paid off handsomely, and by 1914 had resulted in the German chemical industry having 75% of the wo
4、rld market in chemicals. This was based on the discovery of new dyestuffs plus the development of both the contact process for sulphuric acid and the Haber process for ammonia. The later required a major technological breakthrough that of being able to carry out chemical reactions under conditions o
5、f very high pressure for the first time. The experience gained with this was to stand Germany in good stead, particularly with the rapidly increased demand for nitrogen-based compounds (ammonium salts for fertilizers and nitric acid for explosives manufacture) with the outbreak of world warin 1914.
6、This initiated profound changes which continued during the inter-war years (1918-1939).1 化学工业的起源尽管化学品的使用可以追溯到古代文明时代，我们所谓的现代化学工业的发展却是非常近代（才开始的） 。可以认为它起源于工业革命其间，大约在 1800 年，并发展成为为其它工业部门提供化学原料的产业。比如制肥皂所用的碱，棉布生产所用的漂白粉，玻璃制造业所用的硅及 Na2CO3. 我们会注意到所有这些都是无机物。有机化学工业的开始是在十九世纪六十年代以 William Henry Perkin 发现第一种合成染料
7、苯胺紫并加以开发利用为标志的。20 世纪初，德国花费大量资金用于实用化学方面的重点研究，到 1914 年，德国的化学工业在世界化学产品市场上占有 75%的份额。这要归因于新染料的发现以及硫酸的接触法生产和氨的哈伯生产工艺的发展。而后者需要较大的技术突破使得化学反应第一次可以在非常高的压力条件下进行。这方面所取得的成绩对德国很有帮助。特别是由于 1914 年第一次世界大仗的爆发，对以氮为基础的化合物的需求飞速增长。这种深刻的改变一直持续到战后（1918-1939 ） 。Since 1940 the chemical industry has grown at a remarkable rate,
8、 although this has slowed significantly in recent years. The lions share of this growth has been in the organic chemicals sector due to the development and growth of the petrochemicals area since 1950s. The explosives growth in petrochemicals in the 1960s and 1970s was largely due to the enormous in
9、crease in demand for synthetic polymers such as polyethylene, polypropylene, nylon, polyesters and epoxy resins.1940 年以来，化学工业一直以引人注目的速度飞速发展。尽管这种发展的速度近年来已大大减慢。化学工业的发展由于 1950 年以来石油化学领域的研究和开发大部分在有机化学方面取得。石油化工在 60 年代和 70 年代的迅猛发展主要是由于人们对于合成高聚物如聚乙烯、聚丙烯、尼龙、聚脂和环氧树脂的需求巨大增加。.The chemical industry today is a v
10、ery diverse sector of manufacturing industry, within which it plays a central role. It makes thousands of different chemicals which the general public only usually encounter as end or consumer products. These products are purchased because they have the required properties which make them suitable f
11、or some particular application, e.g. a non-stick coating for pans or a weedkiller. Thus chemicals are ultimately sold for the effects that they produce. 今天的化学工业已经是制造业中有着许多分支的部门，并且在制造业中起着核心的作用。它生产了数千种不同的化学产品，而人们通常只接触到终端产品或消费品。这些产品被购买是因为他们具有某些性质适合（人们）的一些特别的用途，例如，用于盆的不粘涂层或一种杀虫剂。这些化学产品归根到底是由于它们能产生的作用而被购
12、买的。2. Definition of the Chemical IndustryAt the turn of the century there would have been little difficulty in defining what constituted the chemical industry since only a very limited range of products was manufactured and these were clearly chemicals, e.g., alkali, sulphuric acid. At present, howe
13、ver, many intermediates to products produced, from raw materials like crude oil through (in some cases) many intermediates to products which may be used directly as consumer goods, or readily converted into them. The difficulty cones in deciding at which point in this sequence the particular operati
14、on ceases to be part of the chemical industrys sphere of activities. To consider a specific example to illustrate this dilemma, emulsion paints may contain poly (vinyl chloride) / poly (vinyl acetate). Clearly, synthesis of vinyl chloride (or acetate) and its polymerization are chemical activities.
15、However, if formulation and mixing of the paint, including the polymer, is carried out by a branch of the multinational chemical company which manufactured the ingredients, is this still part of the chemical industry of does it mow belong in the decorating industry?2 化学工业的定义在本世纪初，要定义什么是化学工业是不太困难的，因为
16、那时所生产的化学品是很有限的，而且是非常清楚的化学品，例如，烧碱，硫酸。然而现在有数千种化学产品被生产，从一些原料物质像用于制备许多的半成品的石油，到可以直接作为消费品或很容易转化为消费品的商品。困难在于如何决定在一些特殊的生产过程中哪一个环节不再属于化学工业的活动范畴。举一个特殊的例子来描述一下这种困境。乳剂漆含有聚氯乙烯/聚醋酸乙烯。显然，氯乙烯（或醋酸乙烯）的合成以及聚合是化学活动。然而，如果这种漆，包括高聚物，它的配制和混合是由一家制造配料的跨国化学公司完成的话，那它仍然是属于化学工业呢还是应当归属于装饰工业中去呢？It is therefore apparent that, beca
17、use of its diversity of operations and close links in many areas with other industries, there is no simple definition of the chemical industry. Instead each official body which collects and publishes statistics on manufacturing industry will have its definition as to which operations are classified
18、as the chemical industry. It is important to bear this in mind when comparing statistical information which is derived from several sources. 因此，很明显，由于化学工业经营的种类很多并在很多领域与其它工业有密切的联系，所以不能对它下一个简单的定义。相反的每一个收集和出版制造工业统计数据的官方机构都会对如何届定哪一类操作为化学工业有自己的定义。当比较来自不同途径的统计资料时，记住这点是很重要的。3. The Need for Chemical Industr
19、yThe chemical industry is concerned with converting raw materials, such as crude oil, firstly into chemical intermediates and then into a tremendous variety of other chemicals. .These are then used to produce consumer products, which make our lives more comfortable or, in some cases such as pharmace
20、utical produces, help to maintain our well-being or even life itself. At each stage of these operations value is added to the produce and provided this added exceeds the raw material plus processing costs then a profit will be made on the operation. It is the aim of chemical industry to achieve this
21、.3 对化学工业的需要化学工业涉及到原材料的转化，如石油 首先转化为化学中间体，然后转化为数量众多的其它化学产品。这些产品再被用来生产消费品，这些消费品可以使我们的生活更为舒适或者作药物维持人类的健康或生命。在生产过程的每一个阶段，都有价值加到产品上面，只要这些附加的价值超过原材料和加工成本之和，这个加工就产生了利润。而这正是化学工业要达到的目的。It may seem strange in textbook this one to pose the question “do we need a chemical industry?” However trying to answer this
22、 question will provide() an indication of the range of the chemical industrys activities, () its influence on our lives in everyday terms, and () how great is societys need for a chemical industry. Our approach in answering the question will be to consider the industrys contribution to meeting and s
23、atisfying our major needs. What are these? Clearly food (and drink) and health are paramount. Other which we shall consider in their turn are clothing and (briefly) shelter, leisure and transport.在这样的一本教科书中提出：“我们需要化学工业吗？ ”这样一个问题是不是有点奇怪呢？然而，先回答下面几个问题将给我们提供一些信息：（1）化学工业的活动范围， （2 ）化学工业对我们日常生活的影响， （3）社会对
24、化学工业的需求有多大。在回答这些问题的时候我们的思路将要考虑化学工业在满足和改善我们的主要需求方面所做的贡献。是些什么需求呢？很显然，食物和健康是放在第一位的。其它我们要考虑的按顺序是衣物、住所、休闲和旅行。(1) Food. The chemical industry makes a major contribution to food production in at least three ways. Firstly, by making available large quantities of artificial fertilizers which are used to repl
25、ace the elements (mainly nitrogen, phosphorus and potassium) which are removed as nutrients by the growing crops during modern intensive farming. Secondly, by manufacturing crop protection chemicals, i.e., pesticides, which markedly reduce the proportion of the crops consumed by pests. Thirdly, by p
26、roducing veterinary products which protect livestock from disease or cure their infections.(1)食物。化学工业对粮食生产所做的巨大贡献至少有三个方面。第一，提供大量可以获得的肥料以补充由于密集耕作被农作物生长时所带走的营养成分。 （主要是氮、磷和钾） 。第二，生产农作物保护产品，如杀虫剂，它可以显著减少害虫所消耗的粮食数量。第三，生产兽药保护家禽免遭疾病或其它感染的侵害。(2) Health. We are all aware of the major contribution which the ph
27、armaceutical sector of the industry has made to help keep us all healthy, e.g. by curing bacterial infections with antibiotics, and even extending life itself, e.g. blockers to lower blood pressure.（2）健康。我们都很了解化学工业中制药这一块在维护我们的身体健康甚至延长寿命方面所做出的巨大贡献，例如，用抗生素治疗细菌感染，用 -抗血栓降低血压。(3) Clothing. The improvemen
28、t in properties of modern synthetic fibers over the traditional clothing materials (e.g. cotton and wool) has been quite remarkable. Thus shirts, dresses and suits made from polyesters like Terylene and polyamides like Nylon are crease-resistant, machine-washable, and drip-dry or non-iron. They are
29、also cheaper than natural .materials.衣物。在传统的衣服面料上，现代合成纤维性质的改善也是非常显著的。用聚脂如涤纶或聚酰胺如尼龙所制作的 T 恤、上衣、衬衫抗皱、可机洗，晒干自挺或免烫，也比天然面料便宜。Parallel developments in the discovery of modern synthetic dyes and the technology to “bond” them to the fiber has resulted in a tremendous increase in the variety of colors availa
30、ble to the fashion designer. Indeed they now span almost every color and hue of the visible spectrum. Indeed if a suitable shade is not available, structural modification of an existing dye to achieve this can readily be carried out, provided there is a satisfactory market for the product.与此同时，现代合成染
31、料开发和染色技术的改善使得时装设计师们有大量的色彩可以利用。的确他们几乎利用了可见光谱中所有的色调和色素。事实上如果某种颜色没有现成的，只要这种产品确有市场，就可以很容易地通过对现有的色彩进行结构调整而获得。Other major advances in this sphere have been in color-fastness, i.e., resistance to the dye being washed out when the garment is cleaned.这一领域中另一些重要进展是不褪色，即在洗涤衣物时染料不会被洗掉。(4) Shelter, leisure and t
32、ransport. In terms of shelter the contribution of modern synthetic polymers has been substantial. Plastics are tending to replace traditional building materials like wood because they are lighter, maintenance-free (i.e. they are resistant to weathering and do not need painting). Other polymers, e.g.
33、 urea-formaldehyde and polyurethanes, are important insulating materials for reducing heat losses and hence reducing energy usage.（4）住所，休闲和旅游。讲到住所方面现代合成高聚物的贡献是巨大的。塑料正在取代像木材一类的传统建筑材料，因为它们更轻，免维护（即它们可以抵抗风化，不需油漆） 。另一些高聚物，比如，脲甲醛和聚脲，是非常重要的绝缘材料可以减少热量损失因而减少能量损耗。Plastics and polymers have made a considerable
34、 impact on leisure activities with applications ranging from all-weather artificial surfaces for athletic tracks, football pitches and tennis courts to nylon strings for racquets and items like golf balls and footballs made entirely from synthetic materials.塑料和高聚物的应用对休闲活动有很重要的影响，从体育跑道的全天候人造篷顶，足球和网球的
35、经纬线，到球拍的尼龙线还有高尔夫球的元件，还有制造足球的合成材料。Likewise the chemical industrys contribution to transport over the years has led to major improvements. Thus development of improved additives like anti-oxidants and viscosity index improves for engine oil has enabled routine servicing intervals to increase from 3000
36、 to 6000 to 12000 miles. Research and development work has also resulted in improved lubricating oils and greases, and better brake fluids. Yet again the contribution of polymers and plastics has been very striking with the proportion of the total automobile derived from these materialsdashboard, st
37、eering wheel, seat padding and covering etc.now exceeding 40%.多年来化学工业对旅游方面所作的贡献也有很大的提高。一些添加剂如抗氧化剂的开发和发动机油粘度指数改进使汽车日产维修期限从 3000 英里延长到 6000 英里再到 12000 英里。研发工作还改进了润滑油和油脂的性能，并得到了更好的刹车油。塑料和高聚物对整个汽车业的贡献的比例是惊人的，源于这些材料挡板，轮胎，坐垫和涂层等等 超过 40%。So it is quite apparent even from a brief look at the chemical indust
38、rys contribution to meeting our major needs that life in the world would be very different without the products of the industry. Indeed the level of a countrys development may be judged by the production level and sophistication of its chemical industry.很显然简单地看一下化学工业在满足我们的主要需求方面所做的贡献就可以知道，没有化工产品人类社会
39、的生活将会多么困难。事实上，一个国家的发展水平可以通过其化学工业的生产水平和精细程度来加以判断。4. Research and Development (R hydrogen and chlorine will react explosively if they are allowed to mix. Chlorine reacts with hydroxide to give hypochlorous acid (HOCI) and chloride (both wasting product and creating by-products). The hypochlorous acid
40、and hypochlorite(ClO)in turn react to give chloratc(ClO3), protons and more chlorideHydroxide reacts at the anode to form oxygenwhich can contaminate the chlorine. All the reactions reduce efficiency and/or create difficult separation or contamination problems that need to be sorted out bcfore any p
41、roducts can be soldThe key to understanding the various types of process used for the electrolysis is the way they separate the reaction productsThere are basically three types of electrolytic cell for brine electrolysis, though there are many variations of detail among the .cells from difierent man
42、ufacturers像其他许多化学品工艺一样，尽管该反应看起来似乎极其简单，但是有一些方面很复杂。首先，该反应的产物必须分开，如果 H2 和 Cl2 允许混合在一起，它们会剧烈反应。H2 和Cl2 反应生成 HOCl 和氯化物（两者均会浪费产物、生成副产物） 。接着，HOCl 和次氯酸盐反应生成氯酸盐（ClO3- ） 、质子和更多的氯化物。 OH 在阳极区反应生成能污染 Cl2 的O2。所有的这些反应可降低效率和（或）引起分解困难或污染问题。因此, 在产物销售之前, 有必要对这些反应清理。理解各种用于电解过程的关键是各种类型的过程分离反应产物的方式。尽管不同的制造商所用的电解槽在细节方面有着多
43、种改变, 但是用于盐水的电解过程的电解槽基本可分为以上三类。4 The Uses of Chlorine and Sodium HydroxideSodium hydroxide has so many chemical uses that it is difficult to classify them convenientlyOne of the largest uses is for papermaking，where the treatment of wood requires a strong alkaliIn some countries this consumes 20of pr
44、oductionAnother 20 is consumed in the manufacture of inorganic chemicals such as sodium hypochlorite(the bleach and disinfectant)Various organic syntheses consume about another fifth of the productionThe production of alumina and soap uses smaller amounts.NaOH 的用途之多，以致很难将它们方便地进行分类。最大的用途之一是用于造纸，造纸业中木
45、材的处理需要强碱。有些国家造纸业中 NaOH 的消耗占其产量的 20%，另外的 20%用于无机化学品（如，次氯酸钠、漂白粉和消毒剂）的生产种有机合成约消耗另外的15%，氧化铝和肥皂的生产需要少量的 NaOH。 。Chlorine is widely used in a variety of other productsAbout a quarter of all production world-wide goes into vinyl chloride，the monomer for making PVCBetween a quarter and a half goes into a vmi
46、ety of other productsDepending on the country，up to 10goes into water purification. Up to 20%goes into the production of solvents (methylchloroform, trichloroethene, ect. ) though many 0f these are being phased out because of the Montreal Protocol. About 10%world-wide goes into the production of ino
47、rganic chlorine -containing compounds. A very significant use in some country for the bleaching of wood pulp，though this is another use coming under environmental pressure. Cl2 广泛用于其它各种产品的生产。在全世界范围内大约有 1/4 的 Cl2 用于生产氯乙烯（生产 PVC 的单体） 。1/4 至 1/2 的 Cl2 用于水的纯化。尽管因为关于消耗臭氧层物质的蒙特利议定书多种溶剂正在被逐步淘汰，但是仍有高达 20%的氯
48、气用于溶剂的生产（如甲基氯仿、三氯乙烯等） 。全世界范围内，大约 10%的 Cl2 用于无机含氯的化合物的生产。尽管 Cl2 用于漂白木材浆是来自环境压力的另一种途径，但是在一些国家 Cl2 的十分重要的用途是用于木材浆的漂白。.UNIT 7Dinitrogen makes up more than three-quarters of the air we breathe，but it is not readily available for further chemical useBiological transformation of nitrogen into useful chemic
49、als is embarrassing for the chemical industry，since all the effort of all the industrys technologists has been unable to find an easy alternative to thisLeguminous plants can take nitrogen from the air and convert it into ammonia and ammoniumcontaining products at atmospheric pressure and ambient temperature；despite a hundred years of effort，the chemical industry still needs high temperatures and pressures of hundreds of atmospheres to do the same jobIndeed，until the invention of the Haber process，all nitrogencontaining chemicals came fr
