Recycling of PBDEs Containing Plastics from Waste Electrical and Electronic Equipment (WEEE): A Review

With the rapid growth of waste electrical and electronic equipment (WEEE) and hindrance to the distribution of recycled polymers due to the presence of polybrominated diphenyl ethers (PBDEs), plastics from WEEE have been an important environmental problem. Currently, the recycling activities on polymeric materials are increasing and becoming more and more important. So, it is imperative to recycle WEEE plastics containing PBDEs in an environmentally sound manner. Based on an overview about PBDEs content in WEEE plastics, three main recycling options have been investigated and a recycling model is established. The emission of PBDE congeners and formation of polybrominated dibenzo dioxins/furans (PBDD/Fs) during various recycling processes is summarized, and the detrimental impact on environment and human health is compared. The review information in this study can provide the basis for environmental friendly management of PBDEs containing plastics.

I. Introduction

With a significant growth in the consumption and frequent upgrading of electrical and electronic equipment (EEE), waste EEE (WEEE) has become one of the fastest growing waste streams on a global scale. In European Union, WEEE is increasing three times as fast as the growth of average municipal waste [1]. Plastics account for about 10–30% of the total amount of WEEE [2], and therefore the increasing volume of plastics from WEEE (seen in Fig. 1) results in an urgent requirement of end-of-life management of WEEE plastics. Since the high recovery quotas set by the European WEEE directive and legal support to environmentally friendly treatment technologies instead of waste disposal (2008/98/EC Directive), the recycling of plastics originating from WEEE have received increasing concerns. As the life cycle assessment (LCA) study revealed, in comparison with incineration and landfill, recycling of WEEE plastics shows lower environmental load and higher efficient use of materials. In 1999, the majority of WEEE plastics collected in Europe, as much as 96%, was landfilled. In recent years, recycling activities on polymeric materials are increasing and becoming more and more important [3]. However, the hazardous substances contained in WEEE plastics represents a major hindrance to the development of recycling technologies, particularly the presence of brominated flame retardants (BFRs). Figure 1. Waste TVs and WEEE plastics stack in Shenzhen China