氨厂热衷于高压反应（其目的是在单程反应器中提高产率）但是当今大多数氨厂采用在较低的压力，很低的单程转化率，同时为节能而选择较低温度。为了确保反应器中的转化率最大，通常在当反应达到平衡时，冷却合成气，使用热交换器或者在反应器的合适位置注入冷却氨，可实现合成气的冷却，这样做的作用是：在反应在尽可能接近平衡使其冷冻停止，因为此反应时放热反应（同时在较高温度下的平衡对氨的合成时不利的）所以为了得到好的收率，可以用这种方法，对热量进行很好的控制。
The output form the Haber stage will consist of a mixture of ammonia and synthesis gas so the next stage needs to be the separation of the two so that the synthesis gas can be recycled. This is normally accomplished by condensing the ammonia (which…- 40 C)
哈伯法的产物由氨和合成气混合物（组成）因此，下一步需要将两者进行分离以能循环利用合成气，这可以压缩氨气得以实现（氨气的挥发度较其他组成小得多，大约在-40℃沸腾
Uses of ammonia. The major use of ammonia is not for the production of nitrogen-containing chemical for further industry use, but for fertilizers such as urea or ammonium nitrates and phosphate. Fertilizers consume 80%of all the ammonia produced．In the USA in 1991,for example, following ammonia-derived products were consumed, mostly for fertilizers (amounts in millions of tonnes): urea(4.2);ammonium sulphate (2.2): ammonium nitrate (2.6);diammonium hydrogen phosphate(13.5).
氨的用途氨的主要用途不是用于进一步应用的含氨化合物的生产, 而是用于生产肥料（如尿素,硝酸铵和磷酸铵）。肥料消耗了所生产氨的80%。例如：在1991 年美国消费的由氨得来的产物如下:其中大部分用作肥料（数量以百万吨计）尿素（4.2 百万吨）硫酸铵（220万吨）,硝酸铵（260万吨），磷酸氢二铵（1350万吨）。
Chemical uses of ammonia are varied．The Solvay process for the manufacture of soda ash uses ammonia, though it does not appear in the final product since it is recycled. A wide variety of processes take ln ammonia directly, including the production of cyanides and aromatic nitrogen -containing compounds such as pyridine. The nitrogen in many polymers (such as nylon of acrylics) can be traced back to ammonia, often via nitriles or hydrogen cyanide．Most other processes use nitric acid or salts derived from it as their source of nitrogen. Ammonium nitrate, used and nitrogen-rich fertilizer, also finds a major use as a bulk explosive.
氨的化学应用各式各样，尽管在制备纯碱的索维尔工艺中氨气得到回收而没出现于最终产品中，但是该过程需要使用氨气，很多过程直接吸收氨气，这些过程包括氰化物和芳香族含氮化合物（如吡啶）的生产。许多聚合物（如尼龙和丙烯酸类聚合物）中的氮可以追溯到氨，通常通过睛或氰（HCN）大多数的其他过称（工艺）以氨制的硝酸或硝酸盐作氮源，硝酸铵，用作含氮的肥料，它的另一种主要用途用作大众化炸药。
2. Nitric Acid 2 硝酸
Production. Much of the nitrogen used by the chemical industry to make other raw materials is not used directly as ammonia rather, the ammonia is first converted into nitric acid Nitric acid production consumers about 20% of all the ammonia produced.
硝酸的生产化学工业制造其他原料时，所用的大部分氮元素不是以氨的形式直接利用，而是先将氨转化为硝酸，硝酸的生产大约消耗所生产的氨的20%
The conversion of ammonia to nitric acid is a three-stage process: 氨生成硝酸的转化反应是一个三步过程：
The first reaction is catalyzed by platinum (in practice platinum-rhodium gauze),as can be observed on the bench with a piece of platinum wire and some concentrated ammonia solution,It might, at first sight, seem that the overall reaction to the acid would be easy;
unfortunately, there are complications as nature is a good deal less tudy than chemists and engineers would prefer.
第一个反应用铂（实际上是铂铑金属网）催化，该催化反应可以再实验室上用一根铂丝和浓氨水溶液观察到。初看起来，生成硝酸的总反应似乎很简单，所不幸的事，实际过程比化学家和工程师所想的要糟的多，因此，存在许多复杂的因素。
Industrially the first reaction is carried out at about 900`C in reactors containing platinum-rhodium gauze, the temperature being maintained by the heat produced by the reaction. At these temperatures some important side reactions are also first. First, the ammonia and air mixture can be oxidized to dinitrogen and water(this … cooled). Secondly the decomposition of the first reaction product, nitric oxide, to dinitrogen and oxygen is promoted by the catalyst. It is therefore important to get the product out of the reactor as fast as possible, though this must be balanced against the need to keep the raw materials in contact with the catalyst long enough for them to react. Thirdly, the product, nitric oxide, reacts with ammonia to give dinitrogen and water, so it is important not to let too much ammonia through the catalyst beds or the result will be wasted raw material that cannot be recovered. Control of these conflicting needs is achieved by careful reactor design and by fine control of temperature and flow-rate through the reactors. The actual contact time is usually about 3*10-4s.
工业上，第一反应于含铂铑金属网的反应器中，在900 度左右进行，温度由该反应产生的热量得以维持，在该温度下，一些重要的副反应也进行得很快，其一，氨和空气混合物能被氧化生成氨气和水（如果反应器器壁的温度高，那么该反应趋向于在壁上进行，因此有必要特意将之冷却），其二，催化剂可促进第一反应的产物NO 的分解，生成氨气和氧气，因此重要的是尽可能快地将产物移出反应器，尽管这一做法与下列事实相矛盾：为使原料和催化剂得以反应，有必要保持原料与催化剂接触时间足够长。其三：反应产物NO 与氨反应生成氨气和水，因此重要的事，不让过多的暗器流过催化剂床层，否则，原料不可回收而浪费。利用精心设计的反应器，控制温度和通过反应器的流速可以实现这些矛盾要素的控制。通常该反应的实际接触时间约3×10-4 秒
The second and third stages have fewer complications, but both are slow and there are no known–cost–effective -catalysts. Typically, a mixture of air and nitric oxide is passed through a series of cooling condensers where partial oxidation occurs, the reaction is favored by low temperatures. the nitrogen dioxide is absorbed from the mixture as it is passed down through a large bubble-cap absorption tower; 55%~60% nitric acid emerges from the bottom. 第二步和第三步反应复杂性较小，但是，两者的反应速度很慢，尚未发现高效的催化剂，一般的，令氨气和NO 的混合物流经一系列的冷凝压缩器，在这些压缩器中发生部分氧化反应，低温对该反应有利。当混合气体流经大型泡罩吸收塔时，NO2 从该混合气体得以吸收，塔底为55%— 60%硝酸
This nitric acid cannot be concentrated much by distillation as it forms an azeotrope with water at 68%citric acid. Nitric acid plants typically employ a tower containing 98% sulphuric acid to give 90% nitric acid from the top of the tower. Near 100% acid can be obtained if necessary by further dehydration with magnesium nitrate.
因为硝酸在68%时与水形成共沸物，所以不能用蒸馏法加工以浓缩，硝酸厂通常利用含98%的硫酸塔在其塔顶去生成90%硝酸，如有必要，利用硝酸镁对之进一步脱水可得到接近100%的硝酸
Uses of nitric acid.About 65% of all the nitric acid produced is reacted with ammonia to make ammonium nitrate; 80% of this is used as fertilizer, the rest as an explosive. The other major use of nitric acid is in organic nitrations. Almost all explosives are ultimately derived
from nitric acid (most …trinitrotoluene). Nitration using mixtures of sulphuric and nitric acid is the first step in the synthesis of important nitro-and amino-aromatic intermediate such as aniline(the first … an amino)．Many important dyestuffs and pharmaceuticals are ultimatelv derived from such reactions，though the quantities involved are small. Polyurethane plastics arc built around aromatic isocyanates ultimately derived from nitrated toluene and benzene, this use consumes about 5%~10% of nitric acid production.
硝酸的用途在所生产硝酸大约有65%与氨反应制造硝酸铵，80%的硝酸铵用于肥料，其余的用作炸药。硝酸的另一个主要作用是用于有机硝化反应，几乎所有的炸药最终都是来自硝酸（大部分为硝酸酯,如硝化甘油或为硝化芳香族化合物如三硝基甲苯）在合成重要的硝基或氨基芳香族中间体时（如苯胺）时，第一步为利用和硝酸的硝化反应。苯胺的合成，第一步为芳香族化合物的硝化，然而将硝基还原为胺基。许多重要的染料和药物最终都是通过该反应得到，尽它们的需求量很小，聚氨酯塑料的制备时以芳香族异氰酸酯为基础，而芳香族异氰酸酯最终来自于硝化甲苯和苯，该用途大约要消耗5%— 10%的硝酸产量 3．Urea
Production. One other product of some significance is made directly from ammonia in 1arge quantities:urea (H2NCONH2). About 20％of all ammonia is made into urea. It is synthesized by high pressure reaction (typically 200～400 atm and 180~210~C) of carbon dioxide with ammonia in a two—stage reaction.
尿素的生产，另一种重要的直接由氨大量生产的产物为尿素，大约有20%的氨用于尿素的生产，尿素是通过CO2 和NH3 的高压反应合成（一般为200— 400 个atm 和180℃— 210℃）该反应可分为两步：
The high pressure reaction achieves about 60％ conversion of carbon dioxide to the carbamate (stage 1) and the resulting mixture is then passed into low—pressure decomposers to allow for the conversion to urea. Unreacted material is passed back to the start of the high-pressure stage of the process as this greatly improves overall plant efficiency．The solution remaining after the second stage can either be used directly as a liquid nitrogenous fertilizer or concentrated to give solid urea of 99.7％purity．
该高压反应可实现将60%的CO2 转化为氨基甲酸酯，生成的混合物输入低压分解器使之转化为尿素，未反应的物料被输回该工艺中高压步骤的开始阶段，这样做可以大大提高车间的总效率，第二阶段所得的溶液可直接用作液态含氮肥料或经浓缩生产纯度为99.7%固体尿素 Uses．The high nitrogen content of urea makes it another useful nitrogenous fertilizer、and this accounts for the vast majority of the market for the compound. Other uses are significant but use only about l 0% of all the urea produced. The biggest other use is for resins (melamine…formaldehyde) which are used, for example, in plywood adhesives and Formica surfaces.
尿素的用途尿素的含氮量高使之成为另一种有利氮肥,尿素占氮肥市场的绝大部分，其他的用途也很重要，但是只占所生产品尿素的10%左右。尿素的最大的另一用途是用于树脂(甲醛二聚氰酰胺和尿素甲醛）例如这些树脂用作胶合板粘结剂和弗莱卡的表面。
Unit 8 Petroleum Processing
Petroleum, the product of natural changes in organic materials over millennia, has accumulated beneath the earth‘s surface in almost unbelievable quantities and has been discovered by humans by humans and used to meet our varied fuel wants. Because it is a mixture of thousands of organic substances, it has proved adaptable to our changing need. It has been adapted, through changing patterns of processing or refining, to the manufacture of a variety of fuels and through chemical changes to the manufacture of a host of pure chemical substances, the petrochemicals.
石油，在有机物材料中经过了上千年的转变，它以一种几乎令人难以置信的数量存在地表，并且已经被人们发现以满足我们对各种燃料的需求。石油是一个非常复杂的混合物，是有机物的混合,因此它能提供我们各种不同的需求，并且通过改变加工或炼制方法生产各种染料，通过化学品的改变生产许多纯的化学物质，即石油化工。
Modern units operate continuously. First a tubular heater supplies hot oil to an efficient distillation column which separates the material by boiling points into products similar to those obtained with the batch still, but more cleanly separated; then later units convert the less salable parts of the crude(… ) into desired salable products. The processes used include various cracking units (… ), polymerization, reforming, hydrocracking, hydrotreating, isomerization, severe processing known as coking, and literally dozens of other processes designed to alter boiling point and molecular geometry.
现代设备连续操作。首先管式加热器向有效的精馏塔提供热的原油，精馏塔通过沸点的不同分离原油，类似于通过间歇蒸馏得到的产品，但是通过这个精馏塔蒸馏出来的产品更干净；然后后面的装置把不畅销的原油转化成畅销的产品。这个过程所用工艺包括各种裂解单元操作（可以把大分子变成小分子），聚合、重整、加氢裂解、加氢处理、异构化、像焦化这种苛刻的工艺和很多其他的工艺过程是设计改变他的沸点和分子结构。 Constituents of Petroleum 石油的构成
Crude petroleum is made up of thousands of different chemical substances including gases liquids, and solids and ranging from methane to asphalt. Most constituents are hydrocarbons, but there are significant amounts of compounds containing nitrogen(...), sulfur(…), and oxygen(…). None constituent exists in large quantity in any crude.原油是由上千种不同的化学物质构成的，包括气体，液体，固体以及从甲烷到沥青。大多数的组分是碳氢化合物，但是也有些重要的化合物包括氮（0~0.5%），硫（0~6%）和氮（0~3.5%）。原油中有很多化学物质但都是少量的。
Aliphatics，or open chain hedrocarbons 脂肪族，或者开链碳氢化合物
n-Paraffin Series or n-alkanes, CnH2n+2. This series comprises a larger fraction of most crudes than any other. Most straight-run () gasolines are predominantly n-paraffins. These materials have poor antiknock properties.
正烷烃系列或正烷烃CnH2n+2. 正烷烃是原油构成的最大部分,与其他成分相比. 大部分的直馏汽油是正烷烃，这些物质抗爆性能较差。
Iso-Praffin Series or Iso-alkanes, CnH2n+2。 These branched chain materials perform better in internal-combustion engines than n-paraffins and hence are considered more desirable. They may be formed by catalytic reforming,alkylation, polymerization, or isomerization. Only small amounts exist in crudes.
异构烷烃系列，或支链烷烃CnH2n+2。 这些支链物质用于内燃机，比正烷烃更受欢迎。他
们可能的形成来源是催化重整，烷基化，聚合或异构化，只有少量支链烷烃存在于原油中。 Olefin, or Alkene Series, CnH2n。 This series is generally absent in crudes, but refining processes such as cracking( ) produce them. These relatively unstable molecules improve the antiknock quality of gasoline, although not as effectively as iso-paraffins. On storage they polymerize and oxidized, which is undesirable. This very tendency to react, however, makes them useful for forming other compounds, petrochemicals, by additional chemical reactions. Ethylene, propylene, and butylene( ) are examples. Cracked gasolines contain many higher member of the series.
烯烃、烯烃系列CnH2n.这个族的化合物在原油中是不存在的,但是有些工艺过程如裂化,能产生他们。这些不稳定的分子改变了汽油的抗爆性,尽管没有异构烷烃那么有效。在反应中他们的聚合和氢化是不希望看到的.但是这种易于反应的性质可以通过其他的化学反应来生产其他的化合物。乙烯,丙烯和丁烯就是很好的例子。裂化汽油包含了这个系列的高分子量的组分。
Ring Compounds环状化合物
Naphthene Series or Cycloalkanes, CnH2n. This series, not to be confused with naphthalene, has the same chemical formula as the olefins，but lacks their instability and reactivity because the molecular configuration permits them to be saturated and unreactive like the alkanes, these compounds are the second most abundant series of compounds in most crudes. The lower members of their group are good fuels; higher molecular weight ones are predominant in gas oil and lubricating oils separated from all types of crudes.
环烷族CnH2n。这个族不能被认为是奈（虽然）他和烯烃有着相同的化学式，但是它缺少烯烃的不稳定性以及容易反应的特点，因为分子结构使他们达到饱和就像烷烃一样不容易反应，这些化合物在大多数原油中占第二位；这族这种分子量较小的是很好的燃料，分子量较大的主要存在于汽油和润滑油种。他们是从各类原油种分离出来的。
Aromatic, or Benzenoid Series, CnH2n-6. Only small amounts of this series occur in most common crudes, but they are very desirable in gasoline since they have high antiknock value, good strong stability, and many uses besides fuels. Many aromatics are formed by refining processes. Examples are:benzene, toluene, ehylbenzene, and xylene．
芳香族CnH2n-6仅仅是有很少的这一族折哦能够的化合物才存在于普通的原油中，但是在汽油中她们是必需的，因为他们有很高的抗爆性, 有很好的稳定性,和其他的很多用途。大多数芳香烃是在精制工艺过程中形成的。例如:苯，甲苯，乙苯和二甲苯。
Lesser Components. Sulfur has always been an undesirable constituent of petroleum. The strong, objectionable odor of its compounds originally brought about efforts eliminate them from gasoline and kerosene fraction. Chemical reactions were at first directed at destroying the odor. Later it was found that sulfur compounds had other undesirable effects ( ). At present, wherever possible, the sulfur compounds are being removed and frequently the sulfur thus removed is recovered as elemental sulfur．Nitrogen compounds cause fewer problems than sulfur compounds, are less objectionable, and are generally ignored.
少量组分。硫通常是是有种不受欢迎的组分部分,这些很强的，具有刺激性气味促使人们将他从汽油和煤中除去。化学反应的最初目的在于去除这些气味。后来人们还发现硫化物的其他效应,（腐蚀, 降低四乙基铅作为抗爆试剂的效应, 空气污染）。目前，只要有可能就把硫化物去掉，并且通常将以硫元素被还原的形式去掉硫化合物。氮化合物引起的问题比硫少, 气味也没有那么难闻, 通常被人们忽略。
With the general adoption of catalytic cracking and finishing processes, it was discovered that the occurrence of metals present only in traces ( ) was troublesome as they are strong catalyst poisons. Now methods to remove these substances are being perfected. Salt has been a major problem for many years. It is practically always present in raw crude, usually as