Packaging hydrocarbons

Van Ormer, H. P,Jr., Better Service from Rotary Screw Air Compressor Packages, Hydrocarbon Processing, p. 181, May (1980). 

The ability to package hydrocarbon solvents in HDPE containers is greatly improved by in situ fluorination using the AIROPAK Process. The barrier properties to toluene are improved 100-fold after fluorination. The propensity of an untreated HDPE container to panel in the presence of toluene is eliminated after fluorination. 

In addition to these uses related to crop production, hydrocarbons are used extensively in packaging, particularly in plastic films and to coat boxes with plastic and (to a much lesser extent) wax. Polymeric resins derived from hydrocarbons are also used to make trays and cases for deflvery of packaged foodstuffs (see Eilmand sheeting materials Packaging Paper). 

Highly branched fractions of nonuniformly branched resins have low molecular weights and are easily soluble, even at room temperature, in saturated hydrocarbons. These highly branched fractions are called extractables, an excessive amount of which in an LLDPE resin can be detrimental to certain end use properties, especially in food packaging appHcations. 

Solids present in oil and synthetic muds must be kept wet with the nonaqueous phase to prevent coagulation and settling and mud instabiUty. Oil-wetting agents are normally incorporated in the basic mud package. These materials are typically amines or quaternary ammonium salts having hydrocarbon chains of 10 or more carbon atoms. They also render clays or lignites oil-wet for use in viscosity and filtration control (128). 

Over time, finish components tend to separate and migrate within the fiber and throughout the yam package. With nylon, the ionic emulsifiers and antistats tend toward the core of the fiber whereas the hydrocarbon lubricants remain on the surface. It is, therefore, essential to scour yams and fabrics at neutral to basic pH to reemulsify the lubricant and remove the finish emulsifier prior to dyeiag. In formulating any new finish, environmental issues such as biodegradabihty, water and air pollution must be considered (137). 

Commercial polystyrenes are normally rather pure polymers. The amount of styrene, ethylbenzene, styrene dimers and trimers, and other hydrocarbons is minimized by effective devolatilization or by the use of chemical initiators (33). Polystyrenes with low overall volatiles content have relatively high heat-deformation temperatures. The very low content of monomer and other solvents, eg, ethylbenzene, in PS is desirable in the packaging of food. The negligible level of extraction of organic materials from PS is of cmcial importance in this appHcation. 

The dephlegmator process recovers a substantially higher purity C2+ hydrocarbon product with 50—75% lower methane content than the conventional partial condensation process. The C2+ product from the cryogenic separation process can be compressed and further separated in a de-ethanizer column to provide a high purity C3+ (LPG) product and a mixed ethylene—ethane product with 10—15% methane. Additional refrigeration for the deethanization process can be provided by a package Freon, propane or propylene refrigeration system. 

The operating environmental temperature has an effect on the carbon canister performance [20]. Fig. 14 shows a 10% degradation in GWC as the environmental temperature increases from 25 to 80 °C. The hydrocarbon heel decreases by 55% during the same test. The hot environment helps to pui ge out the canister, but adsorption is reduced under the same conditions. Ideally the canister would be packaged in an area where it would not pick up heat from vehicle operation. 

Thermoplastic block copolymers were used for pressure-sensitive and hot-melt rubber adhesives as from the middle sixties. These adhesives found application in packaging, disposable diapers, labels and tapes, among other industrial markets. The formulation of these adhesives generally includes an elastomer (generally containing styrene endblocks and either isoprene, butadiene or ethylene-butylene midblocks) and a tackifier (mainly a rosin derivative or hydrocarbon resin). 

The methods of analysis of polymer additives and chemicals, such as hydrocarbons, alcohols, etc., are not only restricted to the field of polymer chemistry but can also be applied for the analysis of such materials in the field of food chemistry. In addition, the analysis of polyaromatic hydrocarbons in edible oils has been of extreme importance. Polymeric packaging materials that are intended for food-contact use may contain certain additives that can migrate into the food products which are actually packaged in such products. The amounts of the additives that are permitted to migrate into food samples are controlled by government agencies in order to show... 

Permeability Different plastics provide different permeability properties. As an example polyethylene will pass wintergreen, hydrocarbons, and many other chemicals. It is used in certain cases for the separation of gases since it will pass one and block another. Chlorotrifluoroethylene and vinyli-dene fluoride, vinylidene chloride, polypropylene, EVA, and phenoxy merit evaluation (Chapter 4, PACKAGING, Permeability). 

Contaminants in recycled plastic packaging waste (HDPE, PP) were identified by MAE followed by GC-MS analysis [290]. Fragrance and flavour constituents from first usage were detected. Recycled material also contained aliphatic hydrocarbons, branched alkanes and alkenes, which are also found in virgin resins at similar concentration levels. Moreover, aromatic hydrocarbons, probably derived from additives, were found. Postconsumer PET was also analysed by Soxhlet extraction and GC-MS most of the extracted compounds (30) were thermally degraded products of additives and polymers, whereas only a few derived from the original contents... 

Several articles with informative bibliographies covering formation protection additives have appeared recently(97,101,102). The exact rock formation sample in question, the ionic strength of the treatment fluid, the preventive additives that are present, the pH of the fluid, and the test procedure employed all have significant effects on the test results. However, with careful experimentation using representative materials a preventive additive package can be administered as part of a water-based fracture treatment to allow effective stimulation of most hydrocarbon reservoirs. Because of this, water-based fracturing fluids are used in approximately 90% of all fracture treatments performed today. 

The sections below review the coordination chemistry of the most important classes of extractants used commercially. Particular attention is paid to the importance of secondary bonding between extractant components. This facilitates the assembly of ligating packages which match the coordination requirements of particular metal cations or their complexes and enhances both the selectivity and strength of extraction. Flydrogen bonding between ligands—e.g., esters of phosphorus(V) acids (see Section 9.17.4.3)—is particularly prevalent in the hydrocarbon solvents commonly used in industrial processes. 

Turbine Package Electrical Fire Hydrocarbon Fire Heat Optical NFPA 30, Section 5-5.5.1. 

The packaging of liquid insecticides and herbicides in specially treated metal containers is problematic owing to corrosion and other problems. The natural choice would be HDPE, but many formulations contain solvents such as xylene and other hydrocarbons that permeate through HDPE, leading to product loss11 and, in many cases, to severe paneling of the container.12,12 1... 

It is known that fluorinated HDPE containers are highly suitable for the packaging of numerous other products such as adhesive systems, oil-based paints, polishes, hand cleaners, and hydrocarbon solvents.12... 

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