Saturated hydrocarbons, production volume

All the products of Clemmensen reductions contain small amounts of un-saturated hydrocarbons. These can be removed by repeated shaking with 10 per cent, of the volume of concentrated sulphuric acid until the acid is colourless or nearly so each shaking should be of about 5 minutes duration. The hydrocarbon is washed with water, 10 per cent, sodium carbonate solution, water (twice), dried with anhydreus magnesium or calcium sulphate, and finally distilled twice from a Claisen flask with fractionating side arm (or a Widmer flask) over sodium. 

Hexachloroethane is not currently produced for commercial distribution in the United States. It is a by-product in the industrial chlorination of saturated and unsaturated C2 hydrocarbons by several U.S. companies, including Dow Chemical, PPG Industries, and Occidental Petroleum Corporation. The product may be used captively in-house or recycled in feedstock to produce tetrachloroethylene or carbon tetrachloride. Estimates of current production volumes were not located (Gordon et al. 1991 Santodonato et al. 1985 TRI93 1995). 

Many studies of saturated hydrocarbons have been carried out over the years we refer the reader to previous reviews by Hummel [1], Swallow [2], and HoLroyd [3]. Here we focus mainly on the last decade and discuss some of the more recent studies. Not too surprisingly, many issues examined in this chapter relate to the topics addressed in our own work we apologize for this deficiency and hope that other reviews in this volume would complement this chapter. Specifically, we concentrate on the early stages of radiolysis and exclude from our scope chemical transformations of secondary radiolytic products, in particular, those derived from the solutes. We also limit our examination to low-LET radiation, such as UV and VUV photons, x- and y-rays, and fast electrons. Significant progress has been made in understanding... 

The heats of combustion of hydrocarbons are presently determined by using a constant volume bomb calorimeter for liquids and solids and a constant pressure flame calorimeter for gases. These measurements can be very accurate (< 1 percent), since they depend mainly on the bath temperature measurement. However, calorimetric measurements cannot be made on-line and require information about the thermal properties of the combustion products of the test sample. Tire technique reported here, on the other hand, is direct, can be performed on-line, and requires no prior knowledge about the exact composition of the test sample. (The only assumption made regarding the composition is that saturated hydrocarbons are the only combustibles present in the test samples). It thus appears that this new technique may be more useful for field operations where on-line measurements of the heats of combustion of the test gases are often needed. 

Depending on the temperature at which the procedure is carried out, an intense red color appear in the zones of bubble collapses, and remains stable, unless the temperature is increased, for about 30 min. We determined that the color is observed only if NO" is in excess in the zone of reaction. We deduce this is the case when NO" is injected into 02-saturated hydrocarbon. As pointed out before, the solubility of diatomic gases from the second period in hydrocarbons is 20—30 mM at ambient conditions (51). The colored patches remaining after NO" injection are about 10 mm long and 1 mm wide, therefore comprise a volume of ca. 10 pi. Typical initial bubble diameter is about 4—6 mm, the initial volume approximately 0.1 ml, which corresponds to 4 pmol of NO" at ambient temperature. After bubble collapse, the NO" concentration is about 100 mM in the reaction zone and therefore in excess over O2. The colored reaction product does not yield any... 

The residual saturation capacity of soil is generally about one third of its waterholding capacity. Immobilization of a certain mass of hydrocarbon is dependent upon soil porosity and physical characteristics of the product. The volume of soil required to immobilize a volume of liquid hydrocarbon can be estimated as follows ... 

The recoverability of hydrocarbon from the subsurface refers to the amount of mobile hydrocarbon available. Hydrocarbon that is retained in the unsaturated zone is not typically recoverable by conventional means. Additional amounts of hydrocarbon that are unrecoverable by conventional methods include the immobile hydrocarbons associated with the water table capillary zone. Residual hydrocarbon is pellicular or insular, and is retained in the aquifer matrix. With respect to recoverability, residual hydrocarbon entrapment can result in volume estimate discrepancies as well as decreases in recovery efficiency. With increasing water saturation, such as when the water table rises via recharge or product removal, hydrocarbons essentially become occluded by a continuous water phase. This results in a reduction of LNAPL and product thickness as measured in the well at constant volume. When water saturation is decreased by lowering the water table (as during recovery operations), trapped hydrocarbons can remobilize, leading to increased recoverability. 

The production of thiophen when acetylene interacts with sulphur vapour has already been mentioned (p. 258). That this product is not the result of a secondary reaction between acetylene and carbon disulphide follows from the fact that thiophen is only produced in quantity from these two reactants at a considerably higher temperature than that required when sulphur is used. Acetylene saturated -with carbon disulphide vapour and passed through an electrically heated tube containing broken porous pot, yields a condensate which at the optimum temperature of 700° C. contains about 10 per cent, by volume of thiophen and 10 per cent, of hydrocarbons.1... 

The first level of compositional information is group-type totals. ASTM Test Method D1319, Hydrocarbon Types in Liquid Petroleum Products by Fluorescent Indicator Adsorption, gives volume percent saturates, olefins, and aromatics in materials that boil below 315 C (600 F). This covers jet fuels but not all diesel fuels, most of which have an end point above 315°C. Despite this limitation, the method has been used widely for diesel fuel due to the lack of a suitable alternative. 

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