Polyamid 2000 plant

The Polyamid 2000 plant in Premnitz, Germany is another nylon 6 carpet recycling facility. For an investment of US 200 million in 2000, the plant was designed to process 264 million pounds per year of carpet and produce 20 million lb/yr of nylon 6 plus 25 million pounds of nylon 6,6 and other engineering plastics271. 

Other companies involved in nylon recycling, primarily for carpet, include Rhodia and Polyamid 2000 A.G. The Polyamid 2000 plant in Premnitz, Germany, mechanically recycles nylon 6,6 and depolymerizes nylon... 

United States production of phenylenediamines is shown ia Table 3 (30). Production of both the m- and -phenylenediamines are not reported siace they are produced captively for use ia the manufacture of polyamides. However, aromatic polyamide plant capacity is about 30,000 t/yr. 

Viscose-polyamide Viscose rayon Viscose rayon plants Viscosities Viscosity... 

Ambient-cure systems are often based on lower molecular-weight soHd epoxy resins cured with aUphatic polyamines or polyamides. Curing normally occurs at ambient temperatures with a working life (pot life) of 8—24 h, depending on the formulation. Epoxy—poly amine systems are typically used for maintenance coatings in oil refineries, petrochemical plants, and in many marine appHcations. Such coverings are appHed by spray or bmsh. These are used widely where water immersion is encountered, particularly in marine appHcations (see COATINGS, MARINE). 

Uses of the polyamide-imides include pumps, valves, gear wheels, accessories for refrigeration plant and electronic components. Interesting materials may be made by blending the polymer with graphite and PTFE. This reduces the coefficient of friction from the already low figure of 0.2 (to steel) to as little as 0.02-0.08. 

This fall, the closed-loop Evergreen Nylon Recycling plant will start up in the US, a joint venture of DSM Chemicals North America and AlliedSignal. The facility will recover 45,000 m.t./year of caprolactam by depolymerising the fibres from 100,000 m.t./year of discarded nylon-6 carpets. Meanwhile in Germany, Lurgi is building the Polyamid 2000 AG facility. It will process 120,000 m.t./year of carpet waste and recover 10,000 m.t./ year of caprolactam from nylon-6 carpets and 13,000 m.t./ year of nylon-6-6 from nylon-6-6 carpets. 

Hexamethylenediamine (HMDA), a monomer for the synthesis of polyamide-6,6, is produced by catalytic hydrogenation of adiponitrile. Three processes, each based on a different reactant, produce the latter coimnercially. The original Du Pont process, still used in a few plants, starts with adipic acid made from cyclohexane adipic acid then reacts with ammonia to yield the dinitrile. This process has been replaced in many plants by the catalytic hydrocyanation of butadiene. A third route to adiponitrile is the electrolytic dimerization of acrylonitrile, the latter produced by the ammoxidation of propene. 

Many analytical techniques are in use for the qualitative and quantitative evaluation of monomers and oligomers extracted from PA6 (GC, differential refrac-tometry, IR, PC, SEC, HPLC, RPLC, etc.). FTIR has been used for quantitative analysis of caprolactam oligomer content (extract %) in polyamide-6 [113], The method, which involves a 3h extraction in boiling methanol, is suitable for process control and plant environment. Kolnaar [114] has used FTIR characterisation of fractional extracts with pentane, hexane, and heptane of HDPE for blow moulding applications. Vinyl acetate in packaging film has similarly been determined by quantitative FUR. 

In earlier times, thin-layer chromatography (TLC), polyamide chromatography, and paper electrophoresis were the major separation techniques for phenolics. Of these methods, TLC is still the workhorse of flavonoid analysis. It is used as a rapid, simple, and versatile method for following polyphenolics in plant extracts and in fractionation work. However, the majority of published work now refers to qualitative and quantitative applications of high-performance liquid chromatography (HPLC) for analysis. Llavonoids can be separated. 

Modifications of the method (dry-column chromatography, vacuum liquid chromatography, VLC, for example) are also of practical use for the rapid fractionation of plant extracts. VLC with a polyamide support has been reported for the separation of flavonol glycosides. ... 

The fiftieth anniversary of the announcement of nylon as the first synthetic organic textile fiber by the Du Pont Co. on October 27,1938 was celebrated as a significant event by the textile industry in 1988 (1,2). The announcement was the culmination of the fundamental research efforts of W. H. Carothers and his team at Du Pont (3). Carothers synthesized diamines from C2 to C18 in order for them to react with a variety of aliphatic dicarboxylic acids to make polyamides for evaluation as fibers (4—10). Alicyclic and aromatic diamines and dicarboxylic acids were also included. Nylon-6,6 was ultimately selected for scale-up and development because of its favorable melting point ( 260° C), best balance of properties, and lower manufacturing cost. The pilot plant for nylon-6,6 was completed in Wilmington, Delaware, in July, 1938, and a product was introduced on the market as Exton brisdes for Dr. West s toothbrushes (2). The first nylon filament plant was built in 1939 at Seaford, Delaware, and nylon stockings went on sale on October 24,1939 only to residents of Wilmington, and then nationally, on May 15, 1940 (2). 

Besides solid-phase extraction, column chromatography is also often used for cleanup and purification of polyphenolics from plant material. Ionic adsorbants (polyvinylpyrrolidone or PVP, polyamides, and Sephadex LH-20) and Amberlite XAD-2 resin have been used to isolate and purify polyphenolics from crude extracts. For the separation of polyphenolics from plant material, column chromatography using Sephadex LH-20, a gel-filtration matrix, is often used with various eluting solvents (Park and Lee, 1996). The most widely used solvents for column chromatography are aqueous methanol and aqueous ethanol. 

Molding plants are universal and can be used for processing a wide range of materials, including polyamides, polyurethanes, epoxy resins, and other RIM-formulations. To give some idea of the technical capabilities of RIM-machines main technological features of a Krauss-Maffei (Germany) unit, known as NBC-RIM-s/ar-40 machine, are listed below. 

Nonetheless a few commercially successful noncellulosic membrane materials were developed. Polyamide membranes in particular were developed by several groups. Aliphatic polyamides have low rejections and modest fluxes, but aromatic polyamide membranes were successfully developed by Toray [25], Chemstrad (Monsanto) [26] and Permasep (Du Pont) [27], all in hollow fiber form. These membranes have good seawater salt rejections of up to 99.5 %, but the fluxes are low, in the 1 to 3 gal/ft2 day range. The Permasep membrane, in hollow fine fiber form to overcome the low water permeability problems, was produced under the names B-10 and B-15 for seawater desalination plants until the year 2000. The structure of the Permasep B-15 polymer is shown in Figure 5.7. Polyamide membranes, like interfacial composite membranes, are susceptible to degradation by chlorine because of their amide bonds. 

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