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The resource utilization of waste glass is mainly divided into two aspects: adding waste glass as a raw material to the production of new glass, and employing it as building materials. Obviously, the resource utilization of waste glass is still in a low value-added stage, which leads to a low recovery rate of waste glass. Thus, how to achieve high value-added utilization of waste glass is a challenging issue. In this study, a combined technology of in-situ deposition and vacuum pyrolysis was proposed to synchronously realize impurities removal of waste glass with residual sauce and prepare high value-added ultra-thin glass. The impurities on waste glass were decomposed into harmless gas like CO 2 (52.99%) and H 2 O (33.34%). Molecular dynamics results showed that impurities were completely decomposed at 1108°C. Abundant small molecules such as CO, H•, OH•, O• were produced, which were the precursors of forming CO 2 and H 2 O. Meanwhile, ultra-thin glass (0.26 mm) was generated by in-situ deposition of waste glass. The prepared ultra-thin glass had uniform element distribution, smooth surface, and no structural defects. Visible light transmittance, dielectric constant and dielectric loss of the ultra-thin glass were 84.85%, 6.79 (1 MHz) and 0.0001-0.04, respectively. It presented excellent photoelectric properties, which had great application potential in the fields of photovoltaic and panel display. This study blazes a new trail for preparing high value-added ultra-thin glass from waste glass containing impurities. : [Display omitted] [ABSTRACT FROM AUTHOR]

The recovery of waste glass is an important issue in the fields of social sustainable development and resource recovery. The removal of organic impurity is the first step in the recovery of waste glass. Currently, desiccation-dissociation technology is advised to remove the organic impurity from waste glass. However, the risks of the organic impurity desiccation-dissociation process of waste glass have not been reported in the literature. In this paper, the environmental risks of the organic impurity desiccation-dissociation process of waste glass were assessed. The assessment results indicated that none of TSP (0.143 mg/m3), PM 10 (0.090 mg/m3), heavy metals in air and residue after desiccation-dissociation were contaminated. However, the gas contained abundant organic contaminants, especially benzene, whose content was up to 5.26%. Molecular dynamics simulation and contaminant formation pathways analysis indicated that the formation of gaseous organic contaminants was because overmuch small molecular free radicals were generated at 200 °C and combined with each other. Hence, reducing the temperature of desiccation-dissociation, wearing gas masks, and placing organic gas contaminant absorption liquids are necessary protective measures. This paper provides scientific data for the green development of organic impurity desiccation-dissociation technology of waste glass. Meanwhile, this paper makes up for the shortage of the environmental information of the organic impurity desiccation-dissociation of waste glass. [Display omitted] • Exposure risk in the desiccation-dissociation process of waste glass was assessed. • Gas after desiccation-dissociation contained abundant organic contaminants. • TSP (0.143 mg/m3), PM 10 (0.090 mg/m3) and heavy metals in air were safe. • Formation mechanism of gaseous contaminants was analyzed by molecular dynamics. [ABSTRACT FROM AUTHOR]

The recovery trend of waste printed circuit boards has changed from stabilization to valued-added recovery, but the low value and complexity components of the nonmetallic resources greatly restrict its development. Therefore, the recovery of nonmetallic components deserves more attention and better guidance. This paper reviews the recent developments of the recycling techniques for nonmetallic components, including pyrolysis, supercritical fluid oxidation, chemical leaching, and direct recycling of synthetic materials. The clean production level, recycling efficiency, and economic value of these methods are the focus of this review. The key to improving the recycling technology for non-metallic component is to remove the harmful elements during the recovery process. In the direction of future development of e-waste recovery, environmental friendliness, value, and efficiency are important equally. The novel idea of debromination to reduce potential pollution prior to subsequent processing and enhance recovery value. It can effectively realize the valued-added preparation of environmental-friendly materials by combined process. The results are expected to give guidance for the future recycling process and provide reference for industrial development. • The latest research progress on recycling nonmetallic components in waste printed circuit boards is reviewed. • The low value and the potential secondary pollution will be the major problems during the nonmetal fraction recycling. • The debromination treatment before the valued-added recovery is the potential development direction. • A new optimized process of recycling nonmetallic components from waste printed circuit boards is proposed. [ABSTRACT FROM AUTHOR]

The recovery and reuse of waste brominated resin, which is a typical plastic waste, is troublesome because it contains toxic brominated flame retardants. Conventional pyrolysis of brominated resin was suggested to be an effective approach for debromination. However, conventional pyrolysis caused high energy consumption and high yield of toxic volatiles. An energy-saving and environment-friendly technology called infrared heating was reported in this study. According to computation of the developed heat transfer models, the critical debromination temperature was 260 °C in infrared heating, which was 271 °C lower than conventional pyrolysis. Meanwhile, no volatile product appeared in the reported technology. In the pyrolysis residue after infrared heating, bromine concentrated orientationally in the fixed and limited area on the resin particles. Free radicals, such as •CH 3 , H•, and Br•, were combined with Br• generated in infrared heating to form the concentrated bromine. Compared to the chaotic distribution of bromine in conventional pyrolysis, the orientational concentration of bromine was a progress for removing and collecting bromine in infrared heating. Moreover, compared to conventional pyrolysis, infrared heating could decrease 76.2% energy consumption. This work contributed to provide the novel technology for recovery of plastic wastes [Display omitted] • Infrared vacuum heating was applied for debromination of brominated resin. • The critical temperature of brominated resin was determined. • Heat transfer models were constructed to study the heat distribution of pyrolysis. • The movement behavior of bromine after pyrolysis was studied. • The energy consumption of infrared heating for debromination was estimated. [ABSTRACT FROM AUTHOR]