of Acid resistant materials From iron Steel making Slag Mohammed N. Al-Mukhtar

Abstract

This study is concerned with the feasibility of producing lining material for acid resistant applications from locally iron slag iron slag from the State Company of iron and Steel Industry at Al-Basrah is milled , sieved and tested analytically and instrumentally (i.e., X-ray diffraction ) to study its composition . The examination shows that the local iron slag consists of four main compounds (i.e., A12O3 ,MgO , Cao , and SiO2 ) besides traces of Mno , Fe2 O3 , Tio2 , Cr2 O3, and sulfur. The experimental work is directed to treat the milled slag chemically with four steps consecutively :20% hydrochloric acid .1 % sodium hydroxide , 20% hydrochloric acid and, 1% sodium hydroxide then the remaining is treated with H2O2 to generate oxygen free radicals that reacts with metal sulfate to remove sulfur as H2S. The resulting material is shaped by cold pressing under pressures ranged between 32 and 105 Mpa and three ranges of sintering temperature 950-1050 0C, 1050-1150 0C and 1 150-1250 0C. Acid resistivity , physical and mechanical properties of the prepared specimens are examined. Data shows in general that at low sintering temperatures begging of liquid Phases is occurred but it doesn't give enough contact to diminish merely all the porosity. This corresponds with a decrease in bulk density , apparent porosity, compressive strength, hardness and chemical resistant whereas an increase in water absorption is noticed . In second sintering temperature rang , enough liquid phase convey all porous and consequently good impact of particles may incorporate the increase in bulk density , apparent porosity , compressive strength , hardness and chemical resistant but a decrease in water absorption is measured. Whereas ,at highest sintering temperature range , the formation of cracks and holes in the structure is noticed because of the eruption of liquid phase that consequently decrease in bulk density, apparent porosity, compressive strength, hardness and chemical resistant, and in return, increase in water absorption is occurred.