Plastic containers: PVC

VACUUM PYROLYSIS OF COMMINGLED PLASTICS CONTAINING PVC. PART II. PRODUCT ANALYSIS... 

The pyrolysis products obtained from a variety of mixed plastics containing PVC are investigated. While hydrochloric acid is the major chlorinated product produced by PVC pyrolysis, other chlorinated hydrocarbons are produced. However, the composition and yield of these compounds are very much dependent upon the other polymers present in the plastic mixture. In... 

R. Miranda, J. Yang, C. Roy and C. Vasile, Vacnnm pyrolysis of commingled plastics containing PVC 1. Kinetic stndy. Polymer Degradation and Stability, 72, 469-491 (2001). 

T. Bhaskar, M. A. Uddin, J. Kaneko, T. Kusaba, T. Matsui, A. Muto, Y. Sakata, and K. Murata, Liquefaction of mixed plastics containing PVC and dechlorination by calcium based sorbent. Energy Fuels., 17, 75-80 (2003). 

Shiraga and Uddin [6] carried out thermal and catalytic degradation of mixed plastic containing PVC. The solid acid catalyst employed in this study is silica-alumina with a chlorine sorbent such as goethite hydrated Iron Oxide FeO (OH). The dechlorination ability effects of contact mode, liquid phase contact, (LP) or vapor phase contact (VP) were studied. Dechlorination results show that the vapor phase contact was more effective for chlorine removal. 

Good resnlts were also achieved by catalytic cracking in the Fnji and BASF [92] processes, in which mixed plastics containing PVC were pyrolyzed over ZHSM-5 [93]. 

The pyrolysis of mixed plastics containing PVC in supercritical water has also been demonstrated [96]. The temperature in the reactor increases from 200°C at the top to 1200°C at the bottom. HCl is generated in the first reaction zone. In the second zone, HCl continues to react with alkali metal and is removed, and residue and fuel gas which mainly consists of H2 and CHj are produced by reaction of plastic waste and supercritical water. In the third reaction zone, part of the residue produced was oxidized and CO and fuel gases were generated. 

A gasification process for mixed plastics containing PVC without special dechlorination equipment was developed by Borgianni [97]. Experimental results showed that addition of Na2C03 can effectively remove the chlorine generated, the concentration of pollutants in gas products is pretty low and the fuel gas obtained can be used directly for power... 

The bound chloride in plastics containing PVC is recovered as hydrogen chloride gas from pyrolysis. Considerable amounts of carbon soot are produced in this reaction. By adding superheated steam and hydrogen, the amount of carbon black produced can be reduced from 8.8 to 2.1 wt-% (13). 

Figure 13.6. Depth profile of phosphorus/chlorine ratio of phosphoric plasticizer containing PVC coated fabric. The average concentration of phosphonis/chlo-rine ratio is 0.04. [Adapted, by permission, from Mon-ney L Jamois-Tasserie M Dubois C Villa F Lallet P Renaud C, Polym. Deg. Stab., 72, No.3, 2001, p.459-68.]...

Miranda, R. Pakdel, H. Roy, C. Vasile, C. Vacuum pyrolysis of commingled plastics containing PVC. II. Product analysis. Polym. Degrad. StabU. 2001, 73,47-67. 

Ashallow plastic pan (PVC) at least 12 14" 1" and a half pint plastic container (PVC) with tightly closing lid. 

Phthalocyanine Blues. a-Copper phthalocyanine blue is a reddish species used primarily in coatings and plastics. Several varieties are marketed. The basic form, the unstable Pigment Blue 15 [147-14-8] (Cl 74160), is used in water-based paints, paints containing weak petroleum solvents, and in certain plastics, eg, PVC, that require mild processing conditions. 

These compounds are particularly advantageous for equipment exposed to low temperatures. This plastic containing chlorinated ethylene does not differ significantly in chemical resistance from rigid PVC, but does have a slightly lower creep strength. 

In the field of plastics, the annual production of polyvinylchloride (PVC) is second only to polyethylene. PVC has long been used in various areas, ranging from agriculture and industry to medical equipment and daily life, due to its well-developed production techniques, easy processing, and low price. However, PVC has its own disadvantages, mainly its low stability toward heat and ultraviolet (UV) light. Also, pure PVC is a very hard material that cannot be easily processed and practically used. Common PVC plastics contain various amounts of plasticizers and other additives, including modifiers, stabilizers, and lubricants. 

Such an experience with one plastic, PVC, makes it doubly important to carefully examine any plastic to be used with a food product. The basic question to be answered is Does the plastic container provide adequate protection to the food product during the entire life cycle of the container Adequate protection of a food product in a polyethylene container implies that there is no undesirable change in the chemical content of the food during storage in the container. Thus, our study is concerned with the ways in which food products can change when stored in polyethylene containers. 

MSWIs can accept virtually any mixed waste stream as long as it falls within its calorific window of 9-13 MJ/kg (hence including material containing regular plastics and PVC content). Furthermore, the heavy metal content should not be excessive (since this can make the quality of the slag not suitable for re-use) and the material should be destructible at the rather low incineration temperature of MSWIs (850 °C). Some waste will not be efficiently destroyed. 

Production, Import/Export, Use, Release, and Disposal. Because of the general confusion in the literature about the nomenclature for octylphthalate esters, historical information about the production and import/export of di- -octylphthalate is not readily available. These values generally must be estimated as a percentage of di(2-ethylhexyl)phthalate production or import/export. The compound is used principally as a plasticizer additive to plastics and PVC resins. It is also used as a dye carrier in plastics production and as a chemical intermediate (EPA 1993a HSDB 1995 Mannsville Chemical Products Corporation 1989 Sittig 1991). Limited information is available about releases of di-n-octylphthalate to environmental media. Even the TRI data, which comprise the most current information available, contain errors as a result of the nomenclature confusion (EPA 1993a Vista Chemical 1992). Data are available about the disposal and regulatory status of the compound (see Chapters 4 and 7). More information on the production and releases of di-ft-octylphthalate is needed to estimate potential exposure to the compound. 

Waldo Semon patented the use of tricresyl phosphate as a plasticizer for PVC in 1933. This was later replaced by the less toxic di-2-ethylhexyl phthalate (DOP), which is now the most widely used plasticizer. The worldwide production of plasticizer is on the order of 3.2 million tons annually. Volume-wise, about 90% of the plasticizers are used with PVC and PVC-containing systems. 

The European Pharmacopoeia identifies di(2-ethylhexyl) phthalate as a substance that may be used in the manufacture of PVC plasticized containers and tubing for human blood and blood components, at a level of not more than 40% in the plastic (Council of Europe, 1997). 

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