Recycling methods for plastics are roughly divided into the categories of mechanical recycling, feedstock recycling, and energy recovery. Because various recycling techniques have been developed and applied depending on discharge sources, properties and forms of plastic waste, as much as 84% of plastic waste is effectively being utilized in Japan today. While the amount of plastic waste has gradually decreased as a result of efforts to transition toward a recycling-oriented society and due to increased consumer awareness regarding reduction of waste, the amount of recycled plastics is actually increasing. The amount of recycled plastics treated by energy recovery has especially seen a marked increase. Where mechanical recycling is concerned, raising the quality of recycled materials has eagerly been pursued with the aim of expanding sales. In 2013, however, China announced import restrictions on plastics making it difficult to find sites that will accept the more low-quality recycled materials. Japan has been feeling the impact of these restrictions since 2017. It is now deemed necessary to implement measures that will strengthen methods for washing and removal of contaminants in order to continue export to China and to promote greater domestic use of recycled materials.

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In response to requirements set by world governments working to reduce CO₂ emissions, the rapid shift toward electrified vehicles by automobile companies is now fully acknowledged. Accelerating the introduction of electrified vehicles onto the auto markets has had varied effects on the automobile companies. This, combined with automatic driving and the introduction of AI in cars, is being termed the most drastic innovation in the industry over the past 100 years. Electrified vehicles have created significant improvements with regard to fuel economy using high efficiency motors and high capacity batteries, however the weight of these vehicles is seeing an increase under current changes. The weight of these vehicles must now be reduced in order to receive the benefits of electric, and we are looking to plastic materials to solve this issue. Until now, plastic materials were used mainly for the interior parts of vehicles however, with the flexibility of form plastics offer we are now also looking at application of plastic materials for electrified vehicles – not only for lightening up the weight but also for improving design. This paper gives an overview of the history of use of plastic materials in automobiles and provides an outlook for future possibilities. Lastly, the author makes reference to issues such as reduction of ASR from ELV.

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Because material recycled plastic tends toward chemical degradation with the occurrence of a break down in the main chain, it is known to exhibit very low mechanical properties. Due to this, it has always been thought that regeneration of its mechanical properties was impossible. This is the main factor for stagnating ratios with regard to material recycling.
　On the other hand, our findings show that the main factor behind low mechanical properties is a physical degradation in inner structure change and in fact, poor mechanical properties can be regenerated to almost the same value as virgin plastics by selecting appropriate molding conditions. We also found that the mechanical properties of injection-molded products greatly depend on the condition of the pelletized plastic. Through the process of this investigation, we discovered new mechanical equipment known as the “melt plastic reservoir.” With the introduction of this equipment, we can produce good pellets in a much more stable way. These findings will contribute substantially to the promotion of material recycling of waste plastics.

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Recent optical identification techniques for waste-plastic sorting are reviewed in this paper. The features of the optical sorting machines—high accuracy, non-contact, and high-speed—provide a single-component plastic recycle resource out of mixed waste plastics. The introduction presents the basic concepts of spectroscopy as it relates to optical sorting. One of the latest developments, hyperspectral imaging in near and mid-wavelength infrared absorption identifications, is then evaluated and specifications are given. There is also a summary of the original optical sorting technique known as Raman scattering identification with a discussion on its advantages and drawbacks. Attempts at identification of black-color plastic are introduced ; they show how mid-wavelength infrared absorption and Raman scattering optical sorting have been utilized. Lastly, the paper explains how x-ray transmission measurement is being applied to remove plastics containing brominated flame retardants in adaptation to RoHS restriction and detect talc contained a lot in plastics from end-of-life vehicles.

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Light and durable carbon fiber is a promising material for improving the fuel economy of automobiles through weight reduction. Although huge amounts of energy are consumed in the manufacturing of carbon fiber, consumption of automobile life cycle energy is expected to greatly reduce with the introduction of carbon fiber recycling. Several physical and chemical methods for recovering carbon fibers from CFRP have already been proposed. Carbon fibers hardly deteriorate in their physical properties, i.e. tensile strength, even when heated in an inert gas atmosphere. It is reported, however, that the physical properties do deteriorate when exposed to oxygen, steam, and strong acid, etc. Removing plastics without damaging the carbon fibers is the technical target for the carbon fiber recycling process. In order to promote the recycling of carbon fiber, it is also important to develop products that utilize recovered carbon fibers and create social systems that will standardize the necessary quality and traceability of the recovered carbon fibers.

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The total amount of plastic waste generated in Japan in 2015 was said to be 9.15 million tons; 18.7% of which was derived from electronic waste. Electronic waste is increasingly becoming a more serious problem throughout the world, and in Japan items subject to the social system are limited and fall under the Home Appliance Recycling Law or the Small Home Appliances Recycling Law. On the other hand, in the EU, each country has a responsibility to collect all types of electronic waste under the WEEE directive. Although social systems in Japan and the EU differ on several points such as their background, number of items and fees, the problems relating to plastic waste treatment are something we both have in common. More electronic waste must be retrieved in collection systems in order to achieve the goal of creating a circular society. In this paper, the social systems for electronic waste treatment applied in Japan and the EU are compared with a focus on plastic recycling systems.

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While halogens, such as chlorine and bromine, improve the safety and functionality of plastic products, its removal from plastics also has an impact on the effectiveness of plastic recycling. High-efficiency recycling of used plastics improves the value of plastic as a secondary material and allows for the collection of useful and rare metals. In this study, we summarize the history of dehalogenation technology and expand on its current state. There is a focus on the perception that halogens are considered troublesome to plastic recycling. In the EU, the quality of plastics as secondary raw materials is now standardized within the circular economy package so this is used here as a base for discussing how to effectively proceed with evaluating the use of plastics in the future.

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