Postconsumer

Poly(ethylene terephthalate) (PET) is one of the most extensively recycled polymeric materials. In 1995, 3.5 x 104 tons of PET were recycled in Europe.1 The main reason for the widespread recycling of PET is its extensive use in plastic packaging applications, especially in the beverage industry as plastic bottles. The consistency in terms of volume and availability of postconsumer bottles from sorting facilities and its high material scrap value create an excellent economic environment for PET recycling. 

The principal solvolysis reactions for PET are methanolysis with dimethyl terephthalate and ethylene glycol as products, glycolysis with a mixture of polyols and BHET as products, and hydrolysis to form terephthalic acid and ethylene glycol. The preferred route is methanolysis because the DMT is easily purified by distillation for subsequent repolymerization. However, because PET bottles are copolyesters, the products of the methanolysis of postconsumer PET are often a mixture of glycols, alcohols, and phthalate derivatives. The separation and purification of the various products make methanolysis a cosdy process. In addition to the major product DMT, methanol, ethylene glycol, diethylene glycol, and 1,4-cyclohexane dimethanol have to be recovered to make the process economical.1... 

Polybutylene terephdialate (PBT) has been produced from PET scrap by transesterification widi 1,4-butanediol.1 In die process, classified and cleaned polymer Bake from postconsumer PET bottles is reacted witit 1,4-butanediol in an extruder. PBT is used as an engineering plastic. Ethylene glycol and tetrahydrol uran produced as by-products are recovered by distillation. 

Ammonolysis of PET involves the reaction of PET with ammonia at temperatures of 70-180°C, usually under pressure in EG. The ammonolysis of PET postconsumer bottles has been canied out at temperatures in the range of 120-180°C and a pressure of ca. 2 MPa for 1-7 h. The TPA diamide formed may be converted to terephthalonitrile. Terephthalonitrile may be hydrogenated to form p-xylylenediamine and l,4-bis(aminomethyl)cyclohexane.12 A low-pressure PET ammonolysis process in EG has been developed. The process is catalyzed by 0.5 wt% zinc acetate at a temperature of 70°C and a PET-NH3 ratio of 1 6 (w/w). The yield of TPA diamide was 87%. 

Groupe TBI is investing about FFr3m to build a 15,0001/ y aromatic polyester polyols plant on a greenfield site at Issoire, near Lyons. The novel, patented process uses postconsumer waste bottles made from PETP as feedstock. PU and modified PIR foams made using the APPs have excellent fire performance and good dimensional stability. GROUPE TBI... 

Over 4 billion PETP bottles will be available for colleetion across Europe in 1999. PUR Products has introduced technology into the UK which involves glycolysis of postconsumer PETP into materials for the manufacture of rigid urethane foams for building insulation. This application offers a substantial new market for aromatic polyester polyols derived from glycolised PETP recyclate. PUR(PRODUCTS)LTD. 

Davos, 22nd-26th March 1993, paper 14/2. 8(13) ADVANCES IN PRODUCING INDUSTRIAL GASES ORIGINATING EROM POSTCONSUMER PLASTIC WASTE Lackner V Michaeli W Institut fuer Kunststoffverarbeitung (Maack Business Services)... 

Manufacture of milk containers using postconsumer HDPE has the potential to significantly lower the GHG emissions and energy due to the... 

Franklin Associates (2010). Final Report. Life cycle inventory of 100% postconsumer HOPE and PET recycled resin from postconsumer containers and packaging. 

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... 

The high sensitivity of XRF for elements of higher atomic weight (e.g. Br, Cl) is of advantage in the identification of plastics in postconsumer waste, and is being used in practice only for separating PVC ... 

The EU Directive on Packaging and Packaging Waste sets a recovery target for used packaging of 25% by 2001 and 50-65% by 2005. It is likely that recycling of postconsumer plastics will require substantial polymer/additive analyses. 

The types of furnish used by a pulp and paper mill depend on the type of product produced and what is readily available. Urban mills use a larger proportion of secondary fibers due to the postconsumer feedstock being close at hand. More rurally located mills are usually close to timber sources and thus may use virgin fibers in a greater proportion. 

Contaminant removal processes depend on the type and source of secondary fiber to be pulped. Mill paper waste can be easily repulped with minimal contaminant removal. Recycled postconsumer newspaper, on the other hand, may require extensive contaminant removal, including deinking, prior to reuse. Secondary fiber is typically used in lower-quality applications such as multiply paper-board or corrugating paper. 

Nomad Press is committed to preserving ancient forests and natural resources. We elected to Amazing Kitchen Chemistry Projects on 30% postconsumer recycled paper, processed chlorine free. As a result, for this printing, we have saved ... 

Every year the U.S. generates about 320 billion lb of what is called municipal solid waste, or postconsumer waste. About 85% of this trash is currently disposed of in landfills. Yet as the amount of solid waste increases—and the Environmental Protection Agency estimates that it will reach 380 billion lb by 2000—a third of the landfills are expected to close in the next five years. Many people are concerned that efforts to deal with the growing quantity of garbage are not moving fast enough. 

The center initially concentrated on reclamation and reuse and developed a technology for the reclamation of postconsumer waste plastics. After only two years, CPRR published nearly 25 reports based on its research and held conferences to provide for transferring the technology. "We want to disseminate the information as widely and in as timely a fashion as we can to help develop the infrastructure that will cause plastics to be included in the recycling stream, says Morrow. 

The process developed at CPRR is said to be similar in its layout to those used in private industry. Most plastic reclamation systems are designed to work with rigid containers, such as PET beverage bottles, and HDPE milk or household product containers, because they are currently the easiest postconsumer items to collect and sort. PET beverage bottles are actually not one, but several materials a PET body (clear or green), a pigmented high-density polyethylene (HDPE) base cup, aluminum cap, label, and adhesives. To separate these components, either a dry or wet separation method based on one or more of the different physical properties of the materials can be used. 

Similarly, Dow has entered into a joint venture agreement with Dom-tar of Canada to operate what the companies hope will be by 1990 a self-sustaining PET and HDPE recycling business. The North American company is expected to take postconsumer plastics and, using a proprietary Dow process, convert them into resins for use in Domtar s manufacturing or to be sold by Dow. 

Freeman Chemical uses about 25 million lb of postconsumer PET bottles and film scrap to make polyols for the production of rigid foams. The company estimates that more than 50% of the laminate foam insulation used for construction is made from recycled material. 

Identification of the materials of construction (i.e., plastics, paper, metal, glass, elastomers, coatings, adhesives, and other such materials) should be identified by a specific product designation (code name and/or code number) and the source (name of the manufacturer) alternate materials of construction should be indicated postconsumer recycled plastic should not be used in the manufacture of a primary packaging component, and if it is used for a secondary or associated component, then the safety and compatibility of the material for its intended use should be addressed appropriately... 

Table 9-1. Major constraints on the recycling of postconsumer plastics. Successful recycling requires Recycling is not suitable for ...

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