Hydration and mechanical properties of Portland cement containing eloxal waste from aluminium industry

Eloxal waste is obtained during the production of aluminium tube and decorative profile. It is composed mainly of aluminium oxide, aluminium hydroxide and other substances. In this study, ability of using eloxal as an additive for rapid hardening of Portland cement is investigated. For this purpose eloxal whose alkalinity was removed by partial refining with water. Then, it was dried following its mixture with Portland cement at different ratios. The development of hydration of cement mixes was examined by using setting times, flexural–compressive strengths, volume expansion, X-ray diffraction and scanning electron microscope (SEM) techniques. It was observed that, setting times were slightly shortened gradually whereas the flexural and compressive strengths were increased for cements which was prepared by adding eloxal to Portland cement at various ratios up to 4% in weight. It is preferred to add 4% eloxal in weight to Portland cement. Therefore, which eloxal can be used in Portland cement acts as an additive where rapid setting and high strength is required.