Research On The Flotation Separation Of Electronic Ceramic Powder And Glass Fiber Resin Of Waste Printed Circuit Board

Although e-waste has caused serious threats on ecological environment and human health, it also contains a lot of components, such as metal, rare noble metals and electronic ceramic and glass fiber resin. Therefore, exploitating a full cleaner recycling technologies has the meanings of environment and resources. Metallic and non-metallic included in e-wastes may be separated by gravity because of the different specific gravity between them; Electronic ceramics and glass fiber resin may be separated through flotation separation based on the different property of surface hydrophobicity and hydrophilism.In this paper, the main pure samples tests are collectors’experiments. Besides, studying the interfacial interactive free energy and forces of samples-water, samples-collectors, samples-bubbles and collectors-water interfaces. Elaborating the mechanism between samples and collectors.Pure sample test results show that glass fiber resin has good natural flotability, while electronic ceramic powder natural flotability is poor. The pH value has little effect on flotability of samples, and flotability achieves the best effect when pH is neutral or weakly alkaline. The collection ability of kerosene on samples is stronger than engine oil and diesel.Interactions between collectors and distilled water show that there are van-der Waals attractive forces and hydrophobic gravity between collectors and distilled water, and hydrophobic gravity plays a dominant role. Collectors dispersed in water depend on hydrophobic attraction.Interactions between the specimen and distilled water indicate that there are hydration films on the surface of glass fiber resin and ceramic powder. Hydrophobic attractive force between glass fiber resin-distilled water is smaller than the hydrophobic attractive force between the electronic ceramic powder-distilled water interface, therefore, the hydration film on glass fiber resin surface is more thin.In aqueous solution, strong hydrophobic attraction exists between glass fiber resin-bubble interfaces. Besides, the hydrophilic-hydrophobic indexs of Samples’surfaces show that fiber glass resin surface is hydrophobic while electronic ceramic powder surface has a strong hydrophilic. The above conclusions are consistent with the natural floatability test sresults of pure samples.Interactions between the sample and collector indicate that there are van-der Waals attractive force and hydrophobic gravity between Glass fiber resin-collector and electronic ceramic powder collector, and hydrophobic gravity plays a leading role. In addition, Lewis acid-base interaction free energy of Glass fiber resin-collector is obviously greater than electronic ceramic powder-collector. It illustrates Collector adsorpt in the glass fiber resin surface stronger. In addition, the more difference of hydrophobic attractive force between two samples and collectors, the more conducive to the flotation separation.