title: Application of pyrolysis process to remove and recover liquid crystal and films from waste liquid crystal display glass.
abstract: Liquid crystal display (LCD) glass mainly consists of polarizing film, liquid crystal and glass substrate. Removing and recovering the liquid crystal and films from the LCD glass effectively has important significance for recovering the other parts. This study proposed a pyrolysis process to recover the organic parts from LCD glass. Through thermal gravimetric analysis, the pyrolysis temperature of the LCD glass could be chosen at 850 K. The removal rate of organic parts from LCD glass reached 87.87 wt%. Pyrolysis products consisted of 66.82 wt% oils, 21.01 wt% gaseous and 12.13 wt% residues. In addition, the oils contained 46.27 wt% acetic acid and 32.94 wt% triphenyl phosphate. Then, the pyrolysis mechanisms and products sources of the liquid crystal glass have been analyzed based on the information of bonds energy. The pyrolysis mechanism analysis proved that the products mainly consisted of acetic acid, triphenyl phosphate and C, which is consistent to the results of GC-MS analysis. A reasonable way has been put forward to recycle the pyrolysis products: acetic acid and triphenyl phosphate can be collected by distillation, the rest oils and gases can be used as fuel and the remained glass can be used to extract indium and to produce building materials.
authors.affiliation: School of Environmental Science and Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, People's Republic of China.
authors.forename: Rixin
authors.initials: R
authors.lastname: Lu
authors.forename: En
authors.initials: E
authors.lastname: Ma
authors.forename: Zhenming
authors.initials: Z
authors.lastname: Xu
mesh_terms: D019342:Acetic Acid / Q000737:chemistry; D002244:Carbon / Q000737:chemistry; D016288:Computer Terminals; D059029:Electronic Waste; D004785:Environmental Pollutants / Q000737:chemistry / Q000302:isolation & purification; D008401:Gas Chromatography-Mass Spectrometry; D005898:Glass; D007202:Indicators and Reagents; D050866:Liquid Crystals / Q000737:chemistry*; D009930:Organic Chemicals / Q000737:chemistry / Q000302:isolation & purification; D010755:Organophosphates / Q000737:chemistry; D059027:Recycling / Q000191:economics / Q000379:methods*; D013818:Thermogravimetry
chemical_list: D004785:Environmental Pollutants; D007202:Indicators and Reagents; D009930:Organic Chemicals; D010755:Organophosphates; D002244:Carbon; D019342:Acetic Acid; C005445:triphenyl phosphate