Vinyl solid waste

NOTE - Petrochemical plants also generate significant amounts of solid wastes and sludges, some of which may be considered hazardous because of the presence of toxic organics and heavy metals. Spent caustic and other hazardous wastes may be generated in significant quantities examples are distillation residues associated with units handling acetaldehyde, acetonitrile, benzyl chloride, carbon tetrachloride, cumene, phthallic anhydride, nitrobenzene, methyl ethyl pyridine, toluene diisocyanate, trichloroethane, trichloroethylene, perchloro-ethylene, aniline, chlorobenzenes, dimethyl hydrazine, ethylene dibromide, toluenediamine, epichlorohydrin, ethyl chloride, ethylene dichloride, and vinyl chloride. 

Other Plastics. A relatively small amount of poly(vinyl chloride) goes into packaging applications and appears in municipal solid waste (25). 

There are many common misconceptions about vinyl. For example, the idea that vinyl is not recycled is untrue. Industrial scrap vinyl has been recycled for years, but in more recent years, post-consumer vinyl recycling is growing, too, with about 3.25 x 103 tons (6.5 x 106 lb) of post-consumer vinyl (primarily botdes) being recycled in the 1990s. When the Council for Solid Waste Solutions (now the American Plastics Council) conducted a nationwide survey in 1991, it found that there were an estimated 1100 municipal recycling programs in place or planned in the United States that include vinyl. 

A great proportion of plastics end its lifetime as a part of the overall solid waste stream where they represent roughly 10 wt%. The typical distribution of plastics in household wastes is shown in Figure 3.1 [3]. The main components are polyolefins low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), high-density polyethylene (HDPE) and polypropylene (PP), accounting for about 67% of the total amount of plastic wastes. Other important components in plastic wastes are polystyrene (PS), poly (vinyl chloride) (PVC) and poly (ethylene terephthalate) (PET). 

Research on solvent based polymer separation processes is by no means in its infancy. One of Ae first studies on mixed plastics was conducted by Sperber and Rosen [24,25] in the mid 1970 s. These investigators used a blend of xylene and cyclohexanone to separate a mixture of polystyrene (PS), poly(vinyl chloride) (PVC), high density polyethylene (HOPE), low density polyethylene (LDPE), and polypropylene (PP) into three separate phases. In adAtion, many United States and foreign patents dating from the 1970 s were granted for the solvent recovery of thermoplastic jwlymers [26-30]. The interest in solvent processes waned in the late 1970 s as the oil crisis eased, but the growing need to develop solutions to Ae solid waste problem has renewed Ae research effort [31-33]. 

For analysis of the differences between incineration with air and oxygen a reference chemical formula for solid waste was generated. Much of the waste is paper and plant refuse composed primarily of cellulose. Plastic, fats and grease, as well as a small amount of protein, were included. Water was included since most waste is damp. Small amounts of chlorine from plastics such as vinyl chloride, and sulfur from protein and rubber were included. Table 8.1 A shows the amounts (in weight percent) of components of the reference waste. Table 8.IB shows the elemental chemical composition of the reference waste derived from the components. 

Summers, J., Mikofalvy, B., and Little, S. Use of X-Ray Fluorescence for Soning Vinyl from Other Packaging Materials in Municipal Solid Waste. Journal of Vinvl Technology 12(3) 161-164, 1990a. 

A technique similar to that described above uses organic polymers produced in contact with solid wastes to embed the wastes in a polymer matrix. Three kinds of pol miers that have been used for this purpose include polybutadiene, urea-formaldehyde, and vinyl ester-styrene pol miers. This procedure is more complicated than is the use of thermoplastics but, in favorable cases, yields a product in which the waste is held more strongly. 

Several approaches are used to isolate and eoneentrate volatile analytes from waste samples for subsequent measurement. Some of these based on headspace analysis involve evaporation of volatile substanees into the space above the sample (headspace) in a closed container. Method 5021, Volatile Organic Compounds in Soils and Other Solid Matrices Using Equilibrium Headspace Analysis, is used to isolate volatile organic compounds, such as benzene, bromomethane, chloroform, 1,4-dichlorobenzene, dichloromethane, styrene, toluene, vinyl chloride, and the xylene isomers, from soil, sediment, or solid waste samples for determination by gas chromatography or gas chromatography/mass spectrometry. 

The styrene monomer first may be polymerized to about 65% conversion in the absence of water, and then the blowing agent (cyclopentane) may be added with additional peroxide. This solution is suspended in water in the presence of potato starch, and the polymerization is finished (74). By another modification a styrene solution of waste polystyrene and peroxide is suspended by poly (vinyl alcohol) in water, and pentane is added to the suspension after the solids content of the oil phase is greater than 70% (133). Polystyrene particles may also be suspended in water by a mixture of poly (vinyl alcohol) and a phenyl sulfonate and then a mixture of equal parts of pentane and catalyzed styrene (8% each on polymer) is diffused into the polymer. The temperature is elevated, and the polymerization is completed (23). 

A solid plastic may be ground to a solid powder and then used to apply a plastic coating to a metal product, either for decorative reasons (color) or for functional performance such as insulation or corrosion resistance. Plastics most often used in this way include nylon, vinyl, acrylic, polyethylene, polypropylene, and epoxy. Coating without solvents is beneficial both economically and environmentally, and 100 percent utilization of material eliminates waste. After the powder is bonded to the metal surface, it is often reheated to flow into a more uniform coating and, in the case of thermosetting resins, to complete the cure reaction. 

Chloroethyl vinyl ether in potable and nonpotable waters and solid and hazardous wastes may be analyzed by EPA Methods based on GC and GC/MS instrumentation (U.S. EPA 1992 1997 Methods 611, 625, 8010, 8270) using a purge and trap or thermal desorption technique. Characteristic masses to identify this compound by GC/MS using electron-impact ionization are 106, 63, and 65. 

The development of a solventless, microwave-assisted Suzuki reaction utilizing a readily recyclable solid catalyst offers numerous benefits. These include the straightforward recovery of both product and catalyst, conservation of energy through the use of microwave irradiation, simple commercial scale up, and low waste protocols due to the absence of solvents. Recently, Kabalka et al. reported such a procedure for the reaction between aryl iodides and arylboronic acids or vinyl boronic adds in the presence of KF-AI2O3 as a base [75a] to provide excellent yields of expected coupled products (Equation 87) [75b],... 

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