Oxidation of mineral oils

A combined addition of a chain-breaking inhibitor and a hydroperoxide-breaking substance is widely used to induce a more efficient inhibition of oxidative processes in polyalkenes, rubbers, lubricants, and other materials [3 8]. Kennerly and Patterson [12] were the first to study the combined action of a mixture, phenol (aromatic amine) + zinc dithiophosphate, on the oxidation of mineral oil. Various phenols and aromatic amines can well serve as peroxyl radical scavengers (see Chapter 15), while arylphosphites, thiopropionic ethers, dialkylthio-propionates, zinc and nickel thiophosphates, and other compounds are used to break down hydroperoxide (see Chapter 17). Efficient inhibitory blends are usually prepared empirically, by choosing such blend compositions that induce maximal inhibitory periods [13],... 

Oxidation of mineral oils By using data in Figure 2.7, discuss the oxidation tendency of mineral oils as a function of base oil, degree of refining and the addition of metals and additives. 

Fio. 9-7. Type of apparatus used for oxidation of mineral oils by James process. 

The earlier references, which state that this powerful oxidant is stable when pure, but explosive when formed as a layer on metallic potassium [1,2], are not wholly correct [3], because the superoxide is manufactured uneventfully by spraying the molten metal into air to effect oxidation [4], Previous incidents appear to have involved the explosive oxidation of unsuspected traces of mineral oil or solvents [3]. However, mixtures of the superoxide with liquid or solid potassium-sodimn alloys will ignite spontaneously after an induction period of 18 min, but combustion while violent is not explosive [3], The additional presence of water (which reduces the induction period) or hydrocarbon contaminant did produce explosion hazards under various circumstances [5], Contact of liquid potassium with the superoxide gives no obvious reaction below 117°C and a controlled reaction between 117 and 177°C, but an explosive reaction occurs above 177°C. Heating at 100°C/min from IT caused explosion at 208°C [6],... 

One must be very cautious about using flavor carriers which contain trace minerals that are pro-oxidants. There is no question that copper and iron will catalyze the oxidation of citrus oils. One will find a significant variation in trace mineral content of commercial flavor carriers. 

The lithium should be added in the form of very small pieces. The pieces are most conveniently prepared as follows. Trim the oxide layer off a small block of lithium metal under mineral oil, grip it with tweezers and rinse the mineral oil off in a beaker of dry ether. Hold the block in the ether vapors momentarily to dry, and then plunge it into a tared beaker of mineral oil for weighing. Cut the block into strips with a sharp knife, remove the pieces one by one, and squeeze them into long flat ribbons with pliers which are frequently dipped into the mineral oil. Cut the ribbons into short sections over another beaker of dry ether, swirl and transfer the pieces to a third beaker of ether to wash off the last traces of mineral oil before adding the lithium to the reaction flask. 

Cerium metal in the form of small rectangular billets approximately 5 X X 2 in. is used in this preparation. The surfaces of the billets are filed down under a bath of mineral oil to ensure removal of any oxide layer. Caution is advised as the metal may be pyrophoric. The billets are rinsed in carbon tetrachloride to remove the mineral oil and are then transferred to the vacuum glove box. All subsequent handling of the metal is done in the vacuum glove box in a high-purity argon or helium gas environment. 

Lubricating oils 132-08, 132-20 and 132-21 are completed from fraction IV with an addition of mineral oil MS-14. Products KRP-1 and KRP-2 are obtained by the thermal-oxidative condensation of tank residue below 250 °C. 

Andreozzi R, Caprio V, Insola A, Marotta R, Sanchirico R. Advanced oxidation processes for the treatment of mineral oil-contaminated waste-waters. Water Res 2000 34 620-628. 

Candy coatings are applied via repeated, successive application of dextrin and sugar solutions, followed by drying. Dextrins and monosubstituted starch hydrolyzates are used in candy coatings because of their clear, appetizing films. In this application, clarity, sheen and reduced cracking are desired. Oxidized waxy maize starches are also used.12 Starch used as an impressionable bed for casting candies is typically dent com starch with several tenths of a percent of mineral oil. The oil causes the starch to retain the imprinted shape for a more precisely formed candy piece. 

I. llosvay s Reagent is prepd in the following manner Dissolve Ig of Cu(NO,). 5H 0 in ca 30ml distd w contained in a 50ml volumetric flask. Add 4ml of coned NH OH soln and 3g of hydroxylamine hydrochloride, NH OH.HCl. Shake until themixt becomes colorless and dilute to volume. If the reagent is protected from oxidation by a layer of mineral oil, or if a piece of Cu wire is added, it will retain its reactivity for a long time. When acetylene or its derivatives are bubbled thru the reagent, red coloration or ppt is produced (Ref X8,p 516)... 

Mineral oil—a mixture of liquid hydrocarbons obtained from petroleum. These are useful as levigating agents to wet and incorporate solid substances (e.g., salicylic acid, zinc oxide) into the preparation of ointments that consist of oleaginous bases as their vehicle. There are two types of mineral oils listed in the US. Pharmacopeia/National Formulary (USP/NF). Mineral oil USP is also called heavy mineral oil with a specific gravity between 0.845 and 0.905 and a viscosity of not less 34.5 cSt (cSt = mm /s) at 40°C. Light mineral oil, NF has a specific gravity between 0.818 and 0.880 and a viscosity of not more than 33.5 cSt. Table 2 lists the commercially available mineral oil fractions. 

Observe normal precautions appropriate to the circumstances and quantity of material handled. Since light mineral oil is combustible, it should not be handled or stored near heat, sparks, or flame. Light mineral oil should not be mixed with or stored with strong oxidants. Inhalation of mineral oil vapors may be harmful. 

The thermal reaction between sulfonates and alkali metal cyanides (equation 16) or potassium hexa-cyanoferrate is more of historical value7 The finely powdered, dry and thoroughly mixed starting materials (equation 17) are heated up to 4(X) °C. For more efficient heat exchange the addition of mineral oil, sand, iron turnings or iron oxide is recommended. In spite of the quite forcing reaction conditions, yields of up to 80% are given in certain cases. ... 

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