Synteza zeolitów z popiołów lotnych wytwarzanych w elektrowniach, jako próba rozszerzenia możliwości utylizacji odpadów
Abstract
SYNTHESIS OF ZEOLITES FROM FLY ASH PRODUCED IN POWER PLANTS AS AN ATTEMPT OF UTILIZATION OF WASTES
Summary
The annual production of more than 150 million tonnes of fly ash is the result of combustion of coal in power plants. About half of this fly ash is disposed as a solid waste. New applications of fly ash and recognizing of new methods of recycling are very important. Elaboration of methods of transformation of fly ash into zeolites is important because of the broad spectrum of industrial and agricultural applications of zeolites. Aluminosilicate glass, mullite, and quartz are the main constituents of ash. Aluminosilicate glass is a suitable starting material for zeolite synthesis as a source of Si and Al. Zeolite NaP 1 and faujasite have been obtained during relatively low-temperature treatment (80 °C) in alkaline solution (3 M NaOH) of ash from power plants from Kraków and its environs. Because of the composition of starting material and high pH value during synthesis the zeolites obtained are characterized by low Si/Al ratio. Low-Si zeolites exhibit usually high ion exchange capacity and a large pore volume. The low temperature treatment suggests that it is possible to expect similar transformation of fly ash at the disposal.
Summary
The annual production of more than 150 million tonnes of fly ash is the result of combustion of coal in power plants. About half of this fly ash is disposed as a solid waste. New applications of fly ash and recognizing of new methods of recycling are very important. Elaboration of methods of transformation of fly ash into zeolites is important because of the broad spectrum of industrial and agricultural applications of zeolites. Aluminosilicate glass, mullite, and quartz are the main constituents of ash. Aluminosilicate glass is a suitable starting material for zeolite synthesis as a source of Si and Al. Zeolite NaP 1 and faujasite have been obtained during relatively low-temperature treatment (80 °C) in alkaline solution (3 M NaOH) of ash from power plants from Kraków and its environs. Because of the composition of starting material and high pH value during synthesis the zeolites obtained are characterized by low Si/Al ratio. Low-Si zeolites exhibit usually high ion exchange capacity and a large pore volume. The low temperature treatment suggests that it is possible to expect similar transformation of fly ash at the disposal.