The Experimental Research Of Lead And Water Glass Recovery From Waste CRT Glass Through Adding Alkali By Melting Process

The waste CRT leaded glass has a continuous network structure,and the lead silicate is embedded in the gap of silicon dioxide and cannot be directly reduced by carbon or carbon monoxide.In this research,a novel and effective technology"the recovery of lead and sodium silicate from waste CRT glass through adding alkaline by melting process".The key to this process is removal of lead from the waste CRT glass by high-temperature melting reduction process and important parameters were studied and analyzed.The recovery of lead in waste CRT glass can effectively avoid the harm of hazardous waste to the environment and human body.In order to improve the recovery rate of lead in the link of preparing sodium silicate frit glass waste CRT in the stage of adding alkili,studied the addition amount of Na₂S,the addition amount of Na₂CO₃,reaction temperature and holding time on the recovery of lead.Sodium sulfide was used as precipitant,sodium carbonate was used as flux,carbon powder was used as reducing agent.The maximum lead recovery rate was approximately 94%,when the optimum adding amount of sodium carbonate,sodium sulfide,carbonate,temperature and holding time were 25%,8%,3.6%,1200?and 120 min,respectively.The results showed that the lead crystal is in good crystal state,and the content of lead is 97.2%.In the experiment of hydrolysis of glass slag,the influence of dissolving temperature,dissolving time and liquid-solid ratio on the dissolution rate of glass slag was studied.Waste CRT glass slag in the optimum reaction condition of preparing sodium silicate phases,namely solution temperature 200?,180 min dissolution time,liquid-solid ratio 2:1.At this time,the dissolution rate of glass slag is about 62%.The detection and analysis of water glass was found to be low in impurities,high quality,strong viscosity and a light grey appearance.The residues microstructure was analysised by scanning electron microscope?SEM?and X-ray diffraction?XRD?,the microstructure characteristics of the residues was loose ball,uniform distribution,typical zeolites material microstructure characteristics,which chemical formula was NaAlSi₂O₆·H₂O.The new technology"the recovery of lead and sodium silicate from waste CRT glass through adding alkaline by melting process",greatly improve the recovery of metallic lead which technological process is simple,practical strongly.It not only has significant economic benefits,also has remarkable ecological value.It provides a new way for the utilization of waste CRT glass,industrial mass production and electronic waste disposal.