Lube oils

Vacuum distillation of the atmospheric residue complements primary distillation, enabli r.ecoyery of heavy distillate cuts from atmospheric residue that will un r o further conversion or will serve as lube oil bases. The vacuum residue containing most of the crude contaminants (metals, salts, sediments, sulfur, nitrogen, asphaltenes, Conradson carbon, etc.) is used in asphalt manufacture, for heavy fuel-oil, or for feed for others conversion processes. 

Residue to lube oil plant, steam cracking plant, FCC... 

Simple conventional refining is based essentially on atmospheric distillation. The residue from the distillation constitutes heavy fuel, the quantity and qualities of which are mainly determined by the crude feedstock available without many ways to improve it. Manufacture of products like asphalt and lubricant bases requires supplementary operations, in particular separation operations and is possible only with a relatively narrow selection of crudes (crudes for lube oils, crudes for asphalts). The distillates are not normally directly usable processing must be done to improve them, either mild treatment such as hydrodesulfurization of middle distillates at low pressure, or deep treatment usually with partial conversion such as catalytic reforming. The conventional refinery thereby has rather limited flexibility and makes products the quality of which is closely linked to the nature of the crude oil used. 

A new countercurrent continuous centrifugal extractor developed in the former USSR (214) has the feature that mechanical seals are replaced by Hquid seals with the result that operation and maintenance are simplified the mechanical seals are an operating weak point in most centrifugal extractors. The operating units range between 400 and 1200 mm in diameter, and a capacity of 70 m /h has been reported in service. The extractors have been appHed in coke-oven refining (see Coal conversion processes), erythromycin production, lube oil refining, etc. 

Lubricants. Petroleum lubricants continue to be the mainstay for automotive, industrial, and process lubricants. Synthetic oils are used extensively in industry and for jet engines they, of course, are made from hydrocarbons. Since the viscosity index (a measure of the viscosity behavior of a lubricant with change in temperature) of lube oil fractions from different cmdes may vary from +140 to as low as —300, additional refining steps are needed. To improve the viscosity index (VI), lube oil fractions are subjected to solvent extraction, solvent dewaxing, solvent deasphalting, and hydrogenation. Furthermore, automotive lube oils typically contain about 12—14% additives. These additives maybe oxidation inhibitors to prevent formation of gum and varnish, corrosion inhibitors, or detergent dispersants, and viscosity index improvers. The United States consumption of lubricants is shown in Table 7. 

Lubricating oils are also used in industrial and process appHcations such as hydrauhc and turbine oils, machine oil and grease, marine and railroad diesel, and metalworking oils. Process oils are used in the manufacture of mbber, textiles, leather, and electrical goods. The distribution of lube oils used in these apphcations in 1992 is as follows automotive, 45711 industrial, 2229 t and process, 1070 t (- SIS, 000 gal) (11). 

Synthetic lubricants are tailored molecules which have a higher viscosity index and a lower volatiUty for a given viscosity than lube oils from... 

Pig. 6. Typical stmctures in lube oil (a) / -paraffin, (b) isoparaffin, (c) cycloparaffin, (d) aromatic hydrocarbon, and (e) mixed aUphatic and aromatic ring... 

The principal valeraldehyde derivatives, -amyl and 2-methylbutyl alcohols, are used predominandy to make ziac diamyldithiophosphate lube oil additives (see Amyl alcohols Lubrication and lubricants), which are employed primarily in automotive antiwear appHcations. Similady, the / -valerate and 2-methylbutyrate esters of pentaerythritol and trimethylolpropane are used ia aeromotive synlube formulations and as refrigerant lubricants. 

Space needs to be provided for the auxiliaries, including the lube oil and seal systems, lube oil cooler, intercoolers, and pulsation dampeners. A control panel or console is usually provided as part of the local console. This panel contains instmments that provide the necessary information for start-up and shutdown, and should also include warning and trouble lights. Access must be provided for motor repair and ultimate replacement needs to be considered. If a steam turbine is used, a surface condenser is probably required with a vacuum system to increase the efficiency. AH these additional systems need to be considered in the layout and spacing. In addition, room for pulsation dampeners required between stages has to be included. Aftercoolers may also be required with knockout dmms. Reference 8 describes the requirements of compressor layouts and provides many useful piping hints. 

The major use of technical grade 4-dodecylphenol is in lube oil additives. 4-Dodecylphenol is converted to a calcium phenolate [50910-68-4] and... 

The largest use of NMP is in extraction of aromatics from lube oils. In this appHcation, it has been replacing phenol and, to some extent, furfural. Other petrochemical uses involve separation and recovery of aromatics from mixed feedstocks recovery and purification of acetylenes, olefins, and diolefins removal of sulfur compounds from natural and refinery gases and dehydration of natural gas. 

Apphcation chemists are most interested in physical and functional properties contributed by the sulfonate moiety, such as solubility, emulsification, wetting, foaming, and detersive properties. Products can be designed to meet various criteria including water solubility, water dispersibility, and oil solubility. The polar SO moiety contributes detersive properties to lube oil sulfonates and dry-cleaning sulfonates. 

Petroleum sulfonates have traditionally been produced by both batch and continuous treatment of petroleum oils with oleum. These processes have been covered in several reviews (138,139). Natural petroleum sulfonates are coproducts in the manufacture of a variety of refined oils, most notably white (mineral) oils, lube oils, and process oils (plasticizer oils for mbber compounding). The feedstocks are selected primarily on the basis of the desired characteristics of the refined oils which generally contain 15—30% aromatics. 

Some commercially important isobutyl derivatives include isobutyl acetate, employed as a replacement solvent for -butyl acetate zinc dialkyldithiophosphate (ZDPP) lube oil additives isobutyl acrylate [106-62-8] and methacrylate [97-86-9] monomers isobutylamines and amino resins (qv). 

The majority (92% in 1988) of the butyraldehyde produced in the United States is converted into 1-butanol and 2-ethyIhexanol (2-EH). 2-EH is most widely used as the di(2-ethylhexyl) phthalate [117-81-7] ester for the plasticisation of flexible PVC. Other uses for 2-EH include production of intermediates for acryflc surface coatings, diesel fuel, and lube oil additives (24). 

Other minor uses of ethyl chloride iaclude blowiag agents for thermoplastic foam (51) and styrene polymer foam (52), the manufacture of polymeric ketones used as lube oil detergents (53), the manufacture of acetaldehyde (qv) (54), as an aerosol propellent (55), as a refrigerant (R-160), ia the preparation of acid dyes (56), and as a local or general anesthetic (57,58). 

Poisons ndInhibitors. Catalyst poisons and inhibitors can come from the fuel, the lube oil, from engine wear and corrosion products, and from air ingestion. There are two types of catalyst poisons one poisons active sites, the other is a masking agent. 

Emission control systems for two-stroke engines depend heavily on an efficient oxidation catalyst. These may be based on Pt and/or Pd. Higher lube oil consumption characteristics of two-stroke engines may result in modification to the lube oil or require the development of oxidation catalysts more resistant to lube oil ash compounds. 

Oil layers on pohshed nickel (lube oil) 68 Paper, thin ... 

An interlock is provided through a centrifugal type of pressure switch (PS) to trip the engine in the case of low lube (lubricating) oil pressure during a run. Since during a. start oil pre.s.sure has not built up, a timer, 7 j is introduced to bypass the trip interlock and avoid a false trip. A relay (contactor), d], is used to provide lube oil pressure interlock. 

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