FAST IDENTIFICATION OF POLYMERS AND ADDITIVES OF MASS CONSUMER PRODUCTS Norbert Eisenreich, Thomas Härdle, Harald Kull, Thomas Rohe Fraunhofer-Institut für Chemische Technologie, PO Box 12 40, 76318 Pfinztal 1 Abstract Growing quantities of plastic waste from electronic mass consumer products demand new concepts for an ecologic and economic recycling process. One key problem is the identification and separation of plastics into pure fractions concerning kind of polymer and its additives like flame retardants and heavy metals. The identification of all types of plastic materials and most critical additives requires application of different methods. A fast scanning spectrometer developed at ICT operating in the near infrared (NIR) spectral range is capable of identifying plastic pieces with an identification rate of up to 10 pieces per second. Also a Laser Break Down Spectroscopy (LBDS) system for identification of additives is discussed based on results obtained by a prototype, which had been developed at ICT, too. 2 Introduction Great quantities of virgin material cause great quantities of plastic waste after its use. This plastic waste, especially of housings of electronic goods, are of substantial value. If sufficiently characterized with respect to flame retardants, heavy metals and fillers, these plastics can have a value of about 500 to 2.000 DM/t depending on type and quality of the material. So, new recycling concepts are necessary to reuse this plastic waste for new high-class products and to minimize chemical waste. An integral recycling operation for mass consumer electronic and electric products has to be based on large scale disassembly processes. Polymer identification and analysis of additives are essential for such an operation. Economic aspects demand fast response times (parts of a second), easy handling and integration in automated or at least semi-automated systems. In this paper a combination of near infrared spectroscopy (NIRS) for polymer identification and laser break down spectroscopy (LBDS) for additive analysis will be discussed. Both systems have been investigated at the Fraunhofer-Institute for Chemical Technology (ICT) and prototypes for polymer identification tasks have been developed . 3 Identification Systems 3.1 Near-Infrared Spectroscopy (NIRS) In the near-infrared (NIR) spectral range (700 to 2,500 nm) molecules absorb light by overtone or combi- nation vibrations [1]. Low absorbance in the NIR allows registration of spectra of bulky samples which are of practical interest in recycling processes. C-H, O-H, N-H and C-O bands observed in NIR spectra are characteristic for polymers and enable identification of most commonly used materials. Further ad- vantages of NIR spectral range are that the photodetectors (Ge, InAs or InGaAs) have short response times and high detectivity. Also, quartz fiber optics with low attenuation and low costs can be used. CARE VISION 2000 Frankfurt 1996 CONFERENCE PAPER