Aliphatic hydrocarbons. See

Aliphatic glycidyl ethers, 10 376-377 Aliphatic hydrocarbons. See also Aliphatics photochemical chlorination of, 19 113 separation of, 10 782-785 Aliphatic hydroxyl, replacement with chloride, 13 821... 

In addition, leaking tanks at a chemical company are believed to have delivered benzene, methylene chloride (CH2CI2), toluene (C6H5CH3), xylene (C6H4(CH3)2) and aliphatic hydrocarbons (see Section 2.7) to the subsurface water. These toxic (some carcinogenic) chemicals vaporize in the cave atmosphere, collect at traps and then rise into homes in a similar way to petroleum fumes. 

Recent ab initio calculations by Streitwieser imply that even LiCH3 is ionic Mechanism of initiation of polymerisation by alkyl lithiums in aromatic hydrocarbon is entirely different from that operating in aliphatic hydrocarbon, see p. 64... 

Solvent naphtha (peroleum), medium heavy, aliphatic hydrocarbons. See Naphtha, medium aliphatic... 

Aliphatic Chemicals. The primary aliphatic hydrocarbons used in chemical manufacture are ethylene (qv), propjiene (qv), butadiene (qv), acetylene, and / -paraffins (see Hydrocarbons, acetylene). In order to be useflil as an intermediate, a hydrocarbon must have some reactivity. In practice, this means that those paraffins lighter than hexane have Httle use as intermediates. Table 5 gives 1991 production and sales from petroleum and natural gas. Information on uses of the C —C saturated hydrocarbons are available in the Hterature (see Hydrocarbons, C —C ). 

Peroxides. These are formed by aerial oxidation or by autoxidation of a wide range of organic compounds, including diethyl ether, allyl ethyl ether, allyl phenyl ether, dibenzyl ether, benzyl butyl ether, n-butyl ether, iso-butyl ether, r-butyl ether, dioxane, tetrahydrofuran, olefins, and aromatic and saturated aliphatic hydrocarbons. They accumulate during distillation and can detonate violently on evaporation or distillation when their concentration becomes high. If peroxides are likely to be present materials should be tested for peroxides before distillation (for tests see entry under "Ethers", in Chapter 2). Also, distillation should be discontinued when at least one quarter of the residue is left in the distilling flask. 

Aliphatic hydrocarbons such as hexane also have been reported to react with PCI3 and AICI3. Surface-active esters of phosphinic acids are obtained in good yields by treatment of the intermediate addition compound with an alcohol or phenol followed by hydrolysis [172] see Eqs. (103) to (105) ... 

Hydraulic fluids themselves cannot be measured in blood, urine, or feces, but certain chemicals in them can be measured. Aliphatic hydrocarbons, which are major components of mineral oil hydraulic fluids and polyalphaolefin hydraulic fluids, can be detected in the feces. Certain components of organophosphate ester hydraulic fluids leave the body in urine. Some of these fluids inhibit the enzyme cholinesterase. Cholinesterase activity in blood can be measured. Because many other chemicals also inhibit cholinesterase activity in blood, this test is not specific for organophosphate ester hydraulic fluids. This test is not available at most doctor s offices, but can be arranged at any hospital laboratory. See Chapters 2 and 6 for more information. 

The third class of hydraulic fluids discussed in this profile is the polyalphaolefins. Polyalphaolefins are synthetic hydrocarbons that are made by oligomerizing alphaolefins such as 1-decene (see Chapters 3,4, and 5). Aliphatic hydrocarbons are the principal components of both mineral oils and polyalphaolefins, but the array of hydrocarbons with differing molecular weights is much narrower in polyalphaolefins than in mineral oils. Certain polyalphaolefins maintain good operational characteristics at low temperatures and have been proposed for use in hydraulic systems in U.S. military aircraft (Kinkead et al. 1992b). 

From elution chromatography, the percentage of aliphatic hydrocarbons, aromatic hydrocarbons and polar compounds were obtained. The percentage of polar compounds in the oil decreased as the catalyst concentration increased (see Figure 1) with mainly an increase in the percentage of aromatic hydrocarbons. There was also a decrease in the percentage of both acids and bases in the oil as the catalyst concentration increases as shown in Figure 1. 

As an example, Table 6.6 presents the values of A h for the reactions of peroxyl radicals with aliphatic hydrocarbons. It follows from the table that the slope of this dependence dE/dH for these groups of reactions changes from zero to unity with the increasing reaction enthalpy (see Figure 6.2). 

Ketones are more reactive than aliphatic hydrocarbons due to the influence of the carbonyl group on the BDE of the adjacent C—H bond (see Table 8.11). 

Molex A version of the Sorbex process, for separating linear aliphatic hydrocarbons from branched-chain and cyclic hydrocarbons in naphtha, kerosene, or gas oil. The process operates in the liquid phase and the adsorbent is a modified 5A zeolite the pores in this zeolite will admit only the linear hydrocarbons, so the separation factor is very large. First commercialized in 1964 by 1992, 33 plants had been licensed worldwide. See also Parex (2). 

Wulff A two-stage process for making acetylene by the pyrolysis of saturated aliphatic hydrocarbons. The feed gas is first pyrolyzed at approximately 1,300°C and then passed into a refractory brick reactor at below 400°C. Developed by R. G. Wulff in California in 1927. Operated in the United States, Brazil, and Europe until the end of the 1960s. See also Ruhr Chemie. 

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