Met_OrgSynthesis

16. Read Text A and answer the questions.

1)How many groups can chemicals from petroleum be divided into?

2)What is the difference between these groups?

3)What is the difference between specification and performance chemicals?

4)Why are chemicals from petroleum often not final products?

17.Give examples of a) specification chemicals; b) performance chemicals.

18.Read Text B and answer the questions.

1)What are chemical plants analogous to?

2)What operations are employed in chemical plants?

3)What equipment is used in chemical plants?

4)Why are the individual units in chemical plants smaller than petroleum refining units?

5)What are the reaction conditions of chemical conversion processes?

6)What factors determine the nature and dimensions of the equipment?

7)What materials are used in the construction of equipment in chemical plants?

19.Say a few words about chemical plants.

20.Read Text C and make a short report on oil refining and petrochemical industry.

TEXT C

(Some extracts from the report made by Minister of the Oil Refining and Petrochemical Industry of Russia at the World Petroleum Congress.)

The oil refining and petrochemical industry of our country has long become an independent branch of industrial production in the national economy system. The efforts of specialists in oil refining and petrochemical branch of industry are directed to solving big scientific, technical and social problems arising in the course of economic development and connected with fuel/energy balance, air and water basin pollution by noxious wastes and exhaust gases, optimum production of oil and petrochemical products and the necessity of improving their throughput.

In the national economy this branch of industry is responsible for the development of oil refining processes, production and quality of motor and fuel oils, lubricants, wax, electrode coke, asphalt and various petrochemical products as well as for the production of rubber and rubber articles. Synthetic rubbers and monomers for their production, various types of carbon black, plasticizers and some other components which are used as a base for various types of rubber – the basic structural material used in the production of tyres – are produced by this branch of industry.

Thus the oil refining and petrochemical industry is responsible not only for the production of raw materials and semiproducts, but also for the manufacture of their derivatives, which are widely used in various branches of industrial production, transport, construction, agriculture, medicine and consumer goods production.

It is one of the largest branches of industry in Russia. It is second in the country after ferrous metal industry by the volume of output realized, and is second in the world by the volume of oil refining, production of carbon black and rubbers.

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TEXT 3. SYNTHETIC RUBBERS

Natural rubber is obtained from the rubber tree Hevea brasillensis. It is a chain polymer of isoprene (methylbutadiene) in which a certain number of bonds remain and can react with vulcanizing agents such as sulphur, thus giving a rubber more rigid structure due to the cross linking of the hydrocarbon chain.

Synthetic rubbers fall into two general classes according to their uses, the general-purpose rubbers and the speciality rubbers.

The most important general-purpose rubbers have been the SBR rubbers made by copolymerization of butadiene and styrene. In the last years, a new family of synthetic rubbers – stereospecific rubbers – have been developed based on the polymerization of diolefins such as butadiene by catalysts of Ziegler/Natta type. In this reaction chains are built up by linking carbon atom 4 of the molecules with carbon atom 1 of another; the double bonds 1-2 and 3-4 disappear and a new double bond emerges and is available for the formation of cross links. The polymer can then exist in either of two configurations with the linkage of the carbon atoms 1 and 4 either on the same side of the plane of the new double bond (cis-configuration) or on opposite sides (trans-configuration).

Products with a cis-configuration are resilient and elastic, as is natural rubber; products with a trans-configuration are hard and inelastic, as are the natural products guttapercha and balata.

More recently, copolymers of ethylene and propylene, EP rubbers, have been developed. Being completely saturated polymers, they are very resistant to oxidation and the effects of light but do not readily vulcanize. Double bonds can be introduced by copolymerizing ethylene, propylene and hexadiene or cyclopentadiene to produce EPT rubbers (ethylene, propylene, terpolymer). Yet another synthetic rubber of the butadiene/styrene type has been developed in the USA under the trade name Thermolastic. It is transparent, resilient, abrasive resistant, waterproof and does not need vulcanization. Similar rubbers, ABS rubbers, are produced by copolymerization of the three monomers, butadiene, styrene and acrylonitrile.

The speciality rubbers are of various types, of which the best known are butyl rubber, nitrile rubber and chloroprene rubber.

Other speciality rubbers include polysulphide, polyether, polyurethane, acrylic and chlorosulphonated rubbers.

The polymerization reactions involved in the production of synthetic rubbers are carried out in solution or in emulsion. By emulsion polymerization the rubber is obtained as a latex and can be used as such for the manufacture of foamed or dipped goods or can be converted to crumb rubber by coagulation.

Tasks on the text

1.Memorize the following words and word combinations.

1. hevea [	] brasillensis	16.EP, epoxy (polymer) – эпоксидный
[`	] – гевея	17.resistant to oxidation – устойчивый
(каучуконосное дерево)		к окислению

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2.	to vulcanize [		] –	18.effect of light – воздействие света
	вулканизировать (резину)			19.terpolymer – тройной сополимер
3.	rigid [	] – жесткий		20.EPT – тройной сополимер этилена
4.	cross linking – поперечная связь			и пропилена
5.	to fall into – зд. делиться на			21.trade name – торговое название
6.	general-purpose–общего назначения			22.transparent – прозрачный
7.	speciality rubber – резина			23.abrasive [		] resistant –
	специального назначения			устойчивый к истиранию
8.	SBR, styrene [		]-	24.waterproof – водонепроницаемый
	butadiene [		]-rubber –	25.ABS,acrylonitrile[		]
	сополимер стирола и бутадиена,			-butadiene styrene – акрилонитрил-
	бутадиен-стирольный каучук			бутадиен-стирол
9.	stereospecific –стереорегулярный,			26.butyl[`	] rubber –бутилкаучук
	стереоупорядоченный			27.nitrile [		] – нитрил
10.available – доступный,				28.foamed – пористый, пенообразный
11.linkage – связь				29.dipped goods – товары,
12.plane – плоскость				полученные путем погружения в
13.resilient [			] – упругий,	латекс; гуммированные продукты
	эластичный			30.crumb – крошка, рассыпчатый
14.gutta-percha [			] –	31.coagulation [		] –
	гуттаперча			коагуляция, свертывание
15.balata [			] – вид каучука,

латекса, для конвейерных лент и элементов ременных передач

2.Practise the pronunciation of the words given. Make sure you know their meanings.

Isoprene [		], diolefins [	],	propylene [`	],
hexadiene [,	],	cyclopentadiene [,	,	],	chloroprene
[`	], polyether [,	], polyurethane [,		].

3.Find the pairs of synonyms.

Bond, produce, emerge, application, artificial, purpose, obtain, linkage, aim, appear, synthetic, use.

4.Find the proper definition.

a) Vulcanization; b) SBR rubber; c) isomerization; d) polymerization.

1.The rearrangement of the carbon skeleton of a molecule.

2.Treating rubber with sulphur.

3.The combination of a number of unsaturated molecules of the same or different compounds to form a single large molecule.

4.Synthetic materials made by copolymerization of butadiene and styrene.

5.Say a few words on: a) Natural rubber. b) The classes of synthetic rubbers.

c)The SBR rubbers. d) Stereospecific rubbers. e) Products with a cisconfiguration. f) Products with a trans-configuration. g) EP rubbers.

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6.Read the text and answer the following questions.

1)What gives the rubber a more rigid structure?

2)What do synthetic rubbers fall into?

3)What process produces the SBR rubbers?

4)What are the stereospecific rubbers based on?

5)What properties have the EP rubbers?

6)What type of rubber has been developed in the USA?

7)What are the best known speciality rubbers?

8)What reactions are involved in the production of synthetic rubbers?

9)What are the polymerization reactions involved in the production of synthetic rubbers carried out in?

10)What is latex used for?

7.Translate into English.

1)Бутиловый каучук получают полимеризацией изобутилена, нитриловый каучук производится полимеризацией бутадиена и акрилонитрита. 2). Спрос на синтетический каучук продолжает увеличиваться. 3) В будущем синтетический каучук потребуется в еще большем количестве. 4) Строительство нефтехимических комплексов с производством синтетического каучука планируется в некоторых районах нашей страны.

8.Read the following text and put questions to the words in bold type.

Butadiene is produced by the catalytic dehydrogenation of n-butane or n-

butylene. More recently it has been found possible to steam-crack hydrocarbon fractions in such a way as to produce large amounts of diolefins as well as olefins. This promises to become the cheapest process for the manufacture of butadiene.

Isoprene is produced by dehydrogenation of isoprene obtained by fractionation of straight-run pentane/isopentane.

Styrene is produced from ethylene and benzene.

The price of the base material, monomers, is an important feature in synthetic rubber manufacture. Ethylene and propylene are cheaply and abundantly available by cracking or steam-cracking petroleum fractions. Before World War II a process was developed for the manufacture of butadiene by first chlorination the C4 fraction (butane/butylene) of cracking gas to produce 2.3-dichlorobutane which was then converted into butadiene by dehydrochlorination.

9.Learn the following dialogue.

-The other day I’ve read about S. Lebedev who devoted all his life to the production of artificial rubbers.

-What material did Lebedev produce synthetic rubber of?

-It was produced of alcohol.

-Why didn’t he use petroleum hydrocarbons for that purpose?

-In those years petroleum refining techniques were low and very little raw materials could be obtained from petroleum.

-Now ethylene and propylene as raw materials for synthetic rubber are produced by cracking petroleum fractions.

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10. Look through text A and say what it is about.

TEXT A

The general-purpose rubbers can be used for most purposes for which natural rubber was formerly the only product available. They are used either alone or in blends with other materials, particularly carbon black, for manufacturing cars and truck tyres, mouldings, extrusions, foot-wear, belting, wire and cable covers, flooring and the whole range of domestic articles. Where necessary they are vulcanized with sulphur or other vulcanizing agents.

The speciality rubbers have mostly been developed to achieve some particular property for specific applications for which general-purpose rubbers would not be technically suitable. They are generally more expensive and are limited in use to the applications for which they are most suited by their individual characteristics, such as resistance to high temperature, resistance to oil and solvents, and high flexural strength.

Butyl rubber is outstandingly impermeable to air and is accordingly widely used for inner tubes and curing bags. It also has good electrical properties and is used in wire and cable covers.

Nitric rubbers are extremely resistant to mineral oils, including aromatic oils, and are used for hoses, tubing and gaskets that come into contact with oil products.

Neорrene is resistant to mineral oils other than aromatics, it is also resistant to ozone and is therefore an excellent material f o r cable covers. Its non-inflammability is important for applications in the building industry.

Ethylene-propylene rubbers, EPR, are outstandingly resistant to ozone and to ageing, and are used for the manufacture of weather strips and window sealings in cars and buildings.

Hypalon rubber is highly resistant to heat and chemicals and, being white, lends itself well to the manufacture of light-coloured articles.

11.Give a title to the text.

12.Read paragraph 1 and answer the question. What are the general-purpose rubbers used for?

13.Read paragraph 2 and answer the question. What properties have the speciality rubbers?

14.Read the rest of the text and answer the questions.

1)What properties has butyl rubber?

2)What is it used for?

3)What properties have nitric rubbers?

4)What are they used for?

5)What is neoprene resistant to?

6)What is it used for?

7)What do you know about ethylene-propylene rubbers?

8)What can you say about hypalon rubber?

15. Say a few words about the uses of synthetic rubbers.

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TEXT 4. POLYETHYLENE

Application. A process for the production of high density (0.959-0.968) polyethylene from 99% ethylene using а two-component catalyst system consisting of: (1) a titanium halide and (2) a cocatalyst based on a new class of aluminum hydride compounds:

Description. The catalyst from the preformation tank R1 is suspended in an aliphatic solvent and then continuously fed to the reactor R2, where is also sent a continuous flow of monomer. Both temperature and pressure are carefully controlled in order to retain polymer quality.

The polymer slurry, discharged from the reactor, is conveyed to a flash vessel (V1) where the reaction is stopped and unreacted monomer and inerts are separated, and finally washed in V2 with an extracting agent, which is recycled from the distillation unit, in order to remove catalyst residues.

The polymer, separated from the solvent and dried, is sent to a conventional blending and extrusion section.

Solvent and extraction agent from the separation and drying units are conveyed to the recovery plant where waxes are removed (V3); finally in the C1 column the recycle solvent is obtained as bottom, and the extraction agent as overhead.

Raw Material and Utility Consumption (Per metric ton of pelletized

polyethylene):
Ethylene, 100%-Kg	1,090
Solvent, Kg	50
Low pressure steam, Kg	2.000
Electric power, Kwh	500
Cooling water, m3	250
Fuel, Mkcal	700

Tasks on the text.

1.Memorize the following words and word combinations.

1.	halide [`	] – галогенид,	13.	extrusion [	] –
	галоидное соединение			экструзия, прессование
2.	cocatalyst – совместный катализатор,		14.	bottom – нижний погон
	катализатор совместного действия		15.	overhead [`	vehed] – верхний
3.	preformation tank – резервуар для			погон
	преобразования катализатора		16.	raw [ ] material – сырье

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4.	flow – течение, поток		17.	recovery [	] plant –
5.	slurry [	– шламообразная		регенерационная установка
	смесь, суспензия		18.	utility [	] consumption
6.	to discharge [	] – сливать,		[	] – расход
	вытекать, опорожнять			воды, пара, электроэнергии
7.	to convey – передавать, сообщать		19.	kwh, kilowatt-hour – кВт/ч,
8.	flash vessel – испаритель			киловатт-час (ед. эл. энергии,
9.	residue [	] – остаток		равная 1000 ватт-час)
10.	extracting 1) выделение 2)		20.	rubber crumb – каучуковая
	извлекающий 3) удаляемый			крошка
11.	recycle 1) повторный цикл; рецикл;		21.	Mckal, Megakilocalorie –
	повторять цикл; 2) рециркуляция,			мегакилокалория, Мккал
	(ре)циркулировать		22.	balling – комкование
12.	conventional – обычный, стандартный		23.	wrapping – викелевка,
				обертывание, защит.покрытие

2.Practise the pronunciation.

Polyethylene		[	],	titanium		[	],	aluminium
[	], hydride [		], aliphatic [			], monomer [`		],
polymer [`	], inert [		], recycle [			], wax [	], continuously
[	],	palletized [		],	polyisoprene [			],
homogenize [		].

3.Look through the text to find the following verbs, give their Russian

equivalents.

To suspend, to feed, to retain, to convey, to separate, to wash, to recycle, to dry, to send, to obtain, to blend, to operate, to envisage.

4.Find the English equivalents.

Полиэтилен высокой плотности, алифатический растворитель, непрерывно подается, как температура, так и давление, непрореагировавший мономер, инертные (неактивные) вещества, экстрагирующий реактив, (рецикловый) рециркулирующий растворитель, колонна.

5.Read the text and answer the questions.

1)What is high density polyethylene produced from?

2)What does a catalyst system consist of?

3)Where is the catalyst continuously fed to?

4)Why are both temperature and pressure carefully controlled?

5)What is conveyed to a flash vessel?

6)What is an extracting agent used for?

7)What can you say about the recovery plant?

6.Describe the process of producing high density polyethylene.

7.Say a few words about raw material and utility consumption.

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Fig. 1. Polyethylene production scheme

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8.Read text “Polyisoprene” and describe the process of polymerizing isoprene.

POLYISOPRENE

Application. A process for polymerizing isoprene in an organic solvent using a two-component catalyst system consisting of: (1) titanium tetrachloride and (2) cocatalyst based on a new class of aluminum hydride compounds:

Description. Fresh and recycled monomers are dried, separated from the polymerization inhibitor and fed to the polymerization line along with the recycle solvent and the catalyst. The polymerization occurs at nearly room temperature and can be performed at a high monomer conversion without gel formation.

After the polymerization line the rubber solution is washed with water to remove the catalyst residues, antioxidant added, and homogenized in a blender. The rubber solution is then sent to the stripping section where a crumb slurry of solventfree rubber is obtained. The overhead stream consists mainly of solvent and unreacted monomer. The solvent, distilled and dried, is recycled to the polymerization line, while the unreacted monomer is partly recycled and partly sent back to its production line.

The rubber crumbs, separated from water on a vibrating screen and dried, are then sent to baling and wrapping.

Raw Material and Utility Consumption (per metric ton of end-product):

Isoprene 100%, Kg	1,030
Polymerization solvent, Kg	50
Electric Power, Kwh	900
Steam, Kg	6,600
Cooling water, m3	500
Process water, m3	20

Product Properties:
1,4-Cis, %	≥ 96
Mooney Viscosity, ML (1 + 4) at 100° С	≥ 80
Ash, %	< 0.1
Volatiles, %	< 0.75
Density	~ 0.92
Gel, %	< 1

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Fig. 2. Polyisoprene production scheme

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