Obtaining of dense and highly porous ceramic materials from metallurgical slag

Abstract

Glass-ceramics in a dense and highly porous form can be obtained from metallurgical slag and waste glass of TV monitors. Using polyurethane foam as pore creator, a highly porous system with porosity of 65 ± 5 %, E-modulus and flexural strength of 8 ± 3 GPa and 13 ± 3.5 MPa respectively can be obtained. This porous material had durability (mass loss) of 0.03 % in 0.1 M HCl that is identical with the durability of a dense composite

Glass-ceramics: Their production from wastes—A Review

“…Another method for producing glass-ceramic foam from silicate wastes was demonstrated by Fidancevska et al [39]. In this study, polyurethane foam and bundles of carbon fibres were the two types of pore creator investigated.…”

“…They were soaked with a slurry formulated with the starting parent glass mixture, and the preforms were subjected to different heat-treatments for drying the slurry, burning-off of the perform, and sintering and crystallisation. This method is known as the replication process [39]. Bearing in mind the original structures of the polymer preform, it was not surprising that foams of uniform open pore structure was obtained; the porosity was 65% with pore diameters ranging from 600 to 800μm.…”

“…The present review is concerned with reuse of waste materials to produce glass-ceramics. The versatility of the glass-ceramic production process is manifested by the many wastes that have been used as raw materials for glass-ceramics, which include coal fly ash [30][31][32][33], mud from zinc hydrometallurgy [34][35][36][37], slag from steel production [13,[38][39][40][41][42][43], ash and slag from waste incinerators [44][45][46][47][48][49][50][51][52][53][54][55][56][57], red mud from alumina production [58], waste glass from lamp and other glass products [59] as well as electric-arc furnace dust and foundry sands [60]. Much work has been carried out on the immobilisation of nuclear waste in glass and ceramic matrices and recently there has been some interest in the use of glass-ceramic matrices for this purpose [61,62].…”

Glass ceramic foams from coal ash and waste glass: production and characterisation

“…A heating rate of 30 K min 21 and a cooling rate of 10 K min 21 were used. The powder mixture was cold compacted without binders at 100 MPa in a 10 mm diameter steel die with a green pellet weight of approximately 0 .…”

“…Instead of using individual polymeric particles, continuous, porous, polymeric preforms have been utilised as pore creators in a number of studies on the fabrication of open porous glass ceramic materials from pure constituents 19 or waste materials. 20,21 By far the simplest technique for producing porous ceramics is based on powder sintering with the incorporation of foaming agents, which is also the method employed in the present investigation. Incorporation of foaming agents generates porosity by emitting gas during reaction at elevated temperatures.…”