Processing oils aromatic-based

Process Oils, Plasticizers. Petroleum-based mbber process oils generally contain a mixture of paraffinic, naphthenic, and aromatic components. These oils vary in composition from grade to grade, but most contain some unsaturated moieties and this unsaturation can compete with the polymer for curatives. Therefore, state of cure can be decreased. This is not easily detected because oil softens the compound which masks the loss of state of cure. 

The first commercial oil-fumace process was put into operation in 1943 by the Phillips Petroleum Co. in Borger, Texas. The oil-fumace blacks rapidly displaced all other types used for the reinforcement of mbber and today account for practically all carbon black production. In the oil-fumace process heavy aromatic residual oils are atomized into a primary combustion flame where the excess oxygen in the primary zone bums a portion of the residual oil to maintain flame temperatures, and the remaining oil is thermally decomposed into carbon and hydrogen. Yields in this process are in the range of 35 to 50% based on the total carbon input. A broad range of product quaHties can be produced. 

Crude oil processing is mainly aimed towards the production of fuels, so only a small fraction of the products is used for the synthesis of olefins and aromatics. In Chapter 3, the different crude oil processes are reviewed with special emphasis on those conversion techniques employed for the dual purpose of obtaining fuels as well as olefmic and aromatic base stocks. Included also in this chapter, are the steam cracking processes geared specially for producing olefins and diolefms. 

FD-MS is also an effective analytical method for direct analysis of many rubber and plastic additives. Lattimer and Welch [113,114] showed that FD-MS gives excellent molecular ion spectra for a variety of polymer additives, including rubber accelerators (dithiocar-bamates, guanidines, benzothiazyl, and thiuram derivatives), antioxidants (hindered phenols, aromatic amines), p-phcnylenediamine-based antiozonants, processing oils and phthalate plasticisers. Alkylphenol ethoxylate surfactants have been characterised by FD-MS [115]. Jack-son et al. [116] analysed some plastic additives (hindered phenol AOs and benzotriazole UVA) by FD-MS. Reaction products of a p-phenylenediaminc antiozonant and d.v-9-lricoscnc (a model olefin) were assessed by FD-MS [117],... 

Abstract The source, composition and suitability of crude oils for base oil production are reviewed. The physical and chemical properties of alkanes, naphthenes and aromatics and their characteristics for lubricant applications are examined. Properties and applications of various base oils are defined and specified. Production of conventional mineral oils is described, including the various processes to remove wax and other deleterious substances, followed by increasingly severe hydrogenation to produce base oils of increased quality and performance. The API categorization of mineral base oils, either direct from the refinery or after hydrotreatment of increasing severity, is described, together with sub-categories. 

Paraffinic base oils are produced from crude oils of relatively high alkane content typical crudes are from the Middle East, North Sea and US mid-continent. This is not an exclusive list, nor does it follow that all North Sea crudes, for example, are suitable for production of paraffinic base oils. The manufacturing process requires aromatics removal (usually by solvent extraction) and de-waxing. 

Process oils Lightly refined base oils or highly aromatic by-product extracts from oil manufacture are used in various industrial products, e.g. plasticisers in automotive tyres, in printing inks and in mould release oils. 

New technology developed continuous operations so that plants became much larger and could make more consistent quality products at lower cost. These new process methods were based on the use of solvents continuous selective solvent extraction for aromatic removal was the process which replaced acid treatment and continuous solvent de-waxing replaced the very labour-intensive cold-pressing technique. Technology has developed further in the last 40 years. Catalytic hydrogenation processes have become the normal method for finishing base oils and a more severe form is used as an alternative to solvent extraction to control aromatics content. 

Process oils are not typical lubricants and are mostly used as processing aids in manufacture. They are generally additive-free mixtures of crude oil hydrocarbons and include products such as (i) medicinal white oils, (ii) technical white oils, (iii) bright process oils and (iv) dark process oils. Medicinal white oils are composed exclusively of isoparaffins and alkylnaphthenes. Technical white oils are less refined products than medicinal white oils and are composed of saturated hydrocarbons, though they may also contain a slight amount of aromatic compounds. Bright process oils include both yellow raffinates and brown distillates. Dark process oils are extracts from solvent refining of mineral base oils. 

Use more flexible aliphatic acids with aromatic bases. Move to more highly substituted acids that destroy crystal symmetry. DECREASE Increase solubility Form oil Melting Point-e- INCREASE Process problems Reduce solubility Use small counter-ions, e.g., Cl", Br". Use aromatic conjugate anions if aromatic base. Use small hydroxy acids if drug has good hydrogen bonding potential. 

Base Oil Processing Sulfur Aromatics Paraffins Naphthenes... 

Chem. Descrip. Quaternary ammonium compd. of bentonite Uses Thixotrope in aliphatic and aromatic solv.-based coatings, alkyds, processed oils, epoxy-esters, and oil-modifled urethanes Features Qrganoclay easy to disp., self-activating Properties 90% < 90 pm particle size dens. 11.93 Ib/gal bulking value 0.084 gal/lb 2.5% max. moisture Tixogel KM ]Sud-Chemie Inc]... 

Processing oils are often necessary to ensure good flow and proper filling of moulds. Unfortunately, the use of these oils can seriously hamper adhesion due to their ability to migrate to the adhesive/rubber interface during vulcanisation and interfere with crossbridging reactions. Lower levels of processing oils are always preferred for best adhesion. Naphthenic oils have the least deleterious effect on adhesion, while aromatic and ester based oils should be avoided if at all possible. 

Molecular structure affects Lube quality. Solvent extraction and dewaxing processes preferentially separate the molecules as shown in Figure 10. Extraction separates -paraffins, /-paraffins, naphthenes and some aromatics fi om the distillate into the raffinate phase. Dewaxing rejects the n-paraffins and some /-paraffins from the raffinate to produce a dewaxed oil or base stock. The dewaxed oil will contain the slice of molecular types as shown in Figure 10. 

Aromatic process oil has been used in high volume with general-purpose elastomers such as SBR because it is relatively inexpensive and very effective in improving processability, especially for those compounds based on SBR. 

ASTM D2226 classifies petroleum process oils used in rubber compounding. This system of classification is based on the test results from ASTM D2007, a column chromatographic method called "clay-gel analysis." This procedure classifies an oil on its content of saturates, aromatics, and polar compounds, as well as asphaltene content. Under this classification system, very aromatic oil is designated Type 101 while aromatic oil is designated Type 102. 

Aromatic oils have been used in rubber because they greatly improve the process-ability of compounds based on general-purpose elastomers, especially SBR. Also, aromatic oil imparts better traction to tire treads. Historically, they were less expensive than other processing oils. 

Proprietary rosin oil blends are used mainly in the tire industry and in belting as a less expensive alternative to using more expensive phenolic tackiflers with aromatic process oil. Rosin oil functions both as a tackifier and as a processing oil for rubber compounds usually based on general-purpose elastomers. As discussed earlier, environmental concerns are now associated with the use of aromatic oils. 

This form of limited-conversion hydrocracking is a process that selectively prepares high quality residues for the special manufacture of base oils of high viscosity index or treating residues having low BMCl for the conversion of heavy fractions to ethylene, propylene, butadiene and aromatics. 

The chemical oil contains ca 50 wt % naphthalene, 6 wt % tar acids, 3 wt % tar bases, and numerous other aromatic compounds. The chemical oil is processed to remove the tar acids by contacting with dilute sodium hydroxide and, in a few cases, is next treated to remove tar bases by washing with sulfuric acid. 

The oil-fiimace process, based on the partial combustion of Hquid aromatic residual hydrocarbons, was first introduced in the United States at the end of World War II. It rapidly displaced the then dominant channel (impingement) and gas-furnace processes because it gave improved yields and better product quahties. It was also independent of the geographical source of raw materials, a limitation on the channel process and other processes dependent on natural gas, making possible the worldwide location of manufacturing closer to the tire customers. Environmentally it favored elimination of particulate air pollution and was more versatile than all other competing processes. 

The petroleum industry is now the principal suppHer of ben2ene, toluene, the xylenes, and naphthalene (see BTX processing Feedstocks). Petroleum displaced coal tar as the primary source for these aromatic compounds after World War II because it was relatively cheap and abundantly available. However, the re-emergence of king coal is predicted for the twenty-first century, when oil suppHes are expected to dwindle and the cost of producing chemicals from coal (including new processes based on synthesis gas) will gradually become more competitive (3). 

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