Mineral oils, analysis

MAJOR USES Used in the manufacture of organic chemical, dyes, perfumes, war gas, polyurethane based adhesives separation of mineral oils analysis of auto fluids methylating agent for amines and phenols. 

This method is applicable for mineral oil fractions whose molecular weight is between 290 and 500 and for < 60% and 40% < Cp< 70%. The analysis is fast, approximately 10 minutes, and the correlation with other methods is satisfactory. 

The concentration of acid impurities is an important indication of the quality of petroleum products and the purity of organic solvents, plasticizers, mineral oils, food fats, and polymers. Methods are used to detect organic acids in such compounds have many disadvantages the alkalimetry - low sensitivity, especially in the determination of weak acids, the extraction-photometric method is laborious, instmmental methods are expensive. In addition, most of methods are commonly unsuitable for direct analysis. 

Major emphasis in studies of N-nitroso compounds in foods has been placed upon volatile nitrosamines, in part because these compounds are relatively easy to isolate from complex matrices by virtue of their volatility. Procedures utilizing atmospheric pressure or vacuum distillation have been used by most investigators, with variations of the method of Fine e al. (2) being among the most popular. This procedure employs vacuum distillation of a mineral oil suspension of the sample with optional addition of water to improve nitrosamine recovery from low moisture content samples (6) The usual approach to prevention of nitrosamine formation during analysis involves adding sulfamic acid or ascorbate to destroy residual nitrite at an early stage of sample preparation. 

On-line SFE-pSFC-FTIR was used to identify extractable components (additives and monomers) from a variety of nylons [392]. SFE-SFC-FID with 100% C02 and methanol-modified scC02 were used to quantitate the amount of residual caprolactam in a PA6/PA6.6 copolymer. Similarly, the more permeable PS showed various additives (Irganox 1076, phosphite AO, stearic acid - ex Zn-stearate - and mineral oil as a melt flow controller) and low-MW linear and cyclic oligomers in relatively mild SCF extraction conditions [392]. Also, antioxidants in PE have been analysed by means of coupling of SFE-SFC with IR detection [121]. Yang [393] has described SFE-SFC-FTIR for the analysis of polar compounds deposited on polymeric matrices, whereas Ikushima et al. [394] monitored the extraction of higher fatty acid esters. Despite the expectations, SFE-SFC-FTIR hyphenation in on-line additive analysis of polymers has not found widespread industrial use. While applications of SFC-FTIR and SFC-MS to the analysis of additives in polymeric matrices are not abundant, these techniques find wide application in the analysis of food and natural product components [395]. 

On-line NPLC-GC-FID and/or FUR analysis has been used in discriminating between paraffin waxes and paraffin oils present in, or migrating between, food packaging and food simulants FID was used for quantitation [967]. In a typical application, online coupled LC-GC-F1D has also been used for the analysis of food contamination by mineral oil from printed cardboard [968]. The technique has revealed that many foods are contaminated with mineral oil products. Grob et al. [969] have determined mineral oil in canned food by on-line LC-LC-GC-F1D. DEHP was determined in salad oil by means of conventional LC-GC [970]. HPLC-GC-MS/MS (ion trap) can serve highly useful purposes in areas of applications such as impurity... 

Mineral Oil Hydraulic Fluids. Only one report was located regarding death in humans following exposure to mineral oil hydraulic fluids. A 14-month-old boy ingested 5-10 cc of a mineral oil hydraulic fluid and died 4 weeks later after developing pneumonia (Perrot and Palmer 1992). Postmortem analysis revealed edema, hemorrhages, and lipoid/oil droplets in the lungs. The attending physicians believed that the development of lipoid pneumonia with marked interstitial pneumonitis eventually led to death. 

Mineral Oil Hydraulic Fluids and Polyalphaolefin Hydraulic Fluids. Limited information about environmentally important physical and chemical properties is available for the mineral oil and water-in-oil emulsion hydraulic fluid products and components is presented in Tables 3-4, 3-5, and 3-7. Much of the available trade literature emphasizes properties desirable for the commercial end uses of the products as hydraulic fluids rather than the physical constants most useful in fate and transport analysis. Since the products are typically mixtures, the chief value of the trade literature is to identify specific chemical components, generally various petroleum hydrocarbons. Additional information on the properties of the various mineral oil formulations would make it easier to distinguish the toxicity and environmental effects and to trace the site contaminant s fate based on levels of distinguishing components. Improved information is especially needed on additives, some of which may be of more environmental and public health concern than the hydrocarbons that comprise the bulk of the mineral oil hydraulic fluids by weight. For the polyalphaolefin hydraulic fluids, basic physical and chemical properties related to assessing environmental fate and exposure risks are essentially unknown. Additional information for these types of hydraulic fluids is clearly needed. 

Mineral Oil Hydraulic Fluids. Methods are available for analysis of the hydrocarbon components of mineral oil hydraulic fluids (predominantly straight and branched chain alkanes) in environmental samples. Some of these methods are summarized in Table 6-3. In general, water and sediment samples are extracted with a suitable solvent in a Soxhlet extractor (for solid samples) or in separatory funnel or shake flask (for liquid samples) (Bates et al. 1984 Peterman et al. 1980). The extract is cleaned up on silica gel or Florisil columns using a nonpolar solvent to elute the nonpolar alkanes. Analysis is usually performed by GC/MS (Bates et al. 1984 Kawamura and Kaplan 1983 Peterman et al. 1980). Method performance has not been reported, although 82% recovery of aliphatic hydrocarbons was reported for rainwater (Kawamura and Kaplan 1983). 

In polymer applications derivatives of oils and fats, such as epoxides, polyols and dimerizations products based on unsaturated fatty acids, are used as plastic additives or components for composites or polymers like polyamides and polyurethanes. In the lubricant sector oleochemically-based fatty acid esters have proved to be powerful alternatives to conventional mineral oil products. For home and personal care applications a wide range of products, such as surfactants, emulsifiers, emollients and waxes, based on vegetable oil derivatives has provided extraordinary performance benefits to the end-customer. Selected products, such as the anionic surfactant fatty alcohol sulfate have been investigated thoroughly with regard to their environmental impact compared with petrochemical based products by life-cycle analysis. Other product examples include carbohydrate-based surfactants as well as oleochemical based emulsifiers, waxes and emollients. 

The data obtained by the analysis have become key remediation criteria and it is essential that the environmental analyst (and others who may use the data) be knowledgeable about the various analytical methods. It is also important to know that minor method deviations may be found from region to region. For example, in terms of nomenclature, itself a complex and often ill-defined area of petroleum science (Chapter 1) (Speight, 1999), the analytical methods may refer to total petroleum hydrocarbons as mineral oil, hydrocarbon oil, extractable hydrocarbon, and oil and grease. 

The various physical constants and functions are used for the identification of complex mixtures such as mineral oils, fatty oils, plastics, resins and silicates. Separation of these products into individual components is generally impossible, and methods had to be developed in which certain structural groupings of the mixtures are considered instead of individual molecules or atoms.To identify such complicated mixtures physical constants could be applied successfully for their structural group analysis and for the prediction of various important technical properties. 

The development of reliable methods for structural analysis of mixtures is very laborious. Physical data of pure compounds may serve as a base for the investigations. It has, however, been proved that not in all cases can these data be simply correlated with those of the mixtures. Thus correlations of physical data of pure, individual hydrocarbons often prove not to be valid in the analysis of mineral oils. In this case physical constants of mineral oil fractions of widely different origin form a more reliable basis for the structural analysis, provided that their structure has been determined by absolute methods. 

RING ANALYSIS AND CARBON-TYPE ANALYSIS OF MINERAL OIL FRACTIONS a. Analytical hydrogenation of mineral oils... 

A diagram has been constructed from which it is possible to determine the number of rings of saturated mineral oil fractions if the specific refraction and the molecular weight are known (Fig. 3). The diagram is called the ring analysis diagram. 

The possibility of using the specific refraction instead of the hydrogen content in the analysis of saturated mineral oil fractions is due to the fact that there exists a linear relationship between the specific refraction and the hydrogen content %H. 

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