Dry Waste Derived Electrodes For Saltwater Desalination And Electrochemical Energy Storage

Human production and life produce amounts of solid wastes.How to effectively recycle these solid wastes becomes a main topic and draw numerous research attention.The electrochemical applications on biomass wet waste derived electrode materials have been widely reported.However,few have been reported on the electrochemical applications on dry waste derived electrodes.Shanghai,China,implemented dry and wet waste classification in 2019,offering opportunities for the effective recovery and,the research and development of dry wastes.This study focuses on the mechanisms and properties of dry waste derived electrodes for saltwater desalination and electrochemical energy storage.The main contents are shown as follows:(1)In view of the raw materials of the porous carbon electrodes for capacitive deionization such as carbon nanotube,graphene,coal and so on,the production process is complex,with the usage of dangerous gases and the waste of natural resources.This study explores an atmospheric-pressure chemical vapor deposition synthesis of porous carbon from a dry waste,the waste cigarette filters,with a micro-pore dominant structure and a high specific surface area at a low activation temperature in an inert atmosphere.The waste cigarette filter derived porous carbon electrodes show promising ion adsorption and saltwater desalination performance.The waste cigarette filter derived porous carbon shows a high carbon content.The alkaline vapor pressure is low at a low activation temperature,effectively preventing the environmental pollution.The synthesis method is compatible with the existing production process for active carbon,and the inert atmosphere is safe and reliable.This study provides a practical method for the synthesis and production of waste cigarette filter derived porous carbon,revealing its practical potentials as capacitive deionization electrodes in saltwater desalination.(2)In view of the poor electrical conductivity of iron oxide as an anode electrode for lithium ion batteries,study usually combines corrosion-resistant and conductive carbon nanotubes,graphene and so on with iron oxide to form composite electrode materials,where the fabrication is complex and costly.The study explores a dry waste,the warm paste powder,with main components of iron oxide and active carbon,as a lithium ion battery anode material.The composites of iron oxide and porous carbon in waste warm paste powder complement with each other,where the carbon material helps to improve the conductivity,showing advantages of both the Faraday characteristics of iron oxide and the electric double layer characteristics of porous carbon materials.The specific surface analysis shows that the waste warm paste powder shows micro-and meso-pore porosity.The cyclic voltammetry analysis shows that the waste warm paste powder exhibits highly Faraday redox capacity.Waste warm paste powder is a seasonality dry waste,which is suitable for large-scale centralized recycling,revealing promising potentials as a battery-type electrochemical electrode material.(3)In view of the research on capacitive deionization,a module for capacitive deionization has been fabricated,and a measuring setup has been built.The module uses acrylic as package material and rubber as sealing material.The measuring setup utilizes a peristaltic pump to pump the saltwater in and out of the sealed module.A parallel pair of positive and negative porous carbon electrodes derived from waste cigarette filters are set in the module to achieve capacitive deionization,and a conductivity meter is utilized to observe the change of ion concentration in the saltwater solution.