Comparison of pozzolanic activity of ilmenite MUD waste to other pozzolans used as an additive for concrete production

Abstract

The article presents a comparison of pozzolanic activity of R-Mud, which is a by-product of TiO2, with known and long-used additives to cement and concrete. Tests were carried out comparing the amount of heat of the hydration of cement and cement with added R-Mud, silica fume, fly ash and trass. The reaction susceptibility of these additives with calcium hydroxide has also been studied using the thermogravimetric method. Results from this method have shown that the reactivity of R-Mud is high and at a similar level to silica fume, while it is much higher than the reactivity of fly ash or natural trass. The high level of pozzolanic reactivity of R-Mud has been confirmed by both isothermal calorimetry and thermogravimetry.

Undissolved Ilmenite Mud from TiO2 Production—Waste or a Valuable Addition to Portland Cement Composites?

“…Additional pozzolan additives used in the study are standard additives used in the concrete industry. Some have been described in detail by the authors in a previous paper [ 4 , 39 , 40 ] and are presented in Table 1 .…”

“…Additional pozzolan additives used in the study are standard additives used in the concrete industry. Some have been described in detail by the authors in a previous paper [4,39,40] and are presented in Table 1. 1 Determined by Blane method except for the silica fume which was measured by BET method (Brunauer-Emmett-Teller surface area analysis).…”

Ilmenite Mud Waste as an Additive for Frost Resistance in Sustainable Concrete

“…As a reference concrete, the same mix was used but in place of RMUD the fly ash (FA) has been added. Authors have chosen a reference concrete with fly ash instead of the concrete with only Portland cement as a binder because previous tests have shown [ 21 , 40 ] that the RMUD has a similar level of pozzolanic activity as fly ash.…”

“…Because ilmenite mud waste contains some amounts of unleached TiO 2 the concrete containing this waste might also have a photocatalytic effect helping to reduce the NOx level in the air [ 19 , 20 ]. The waste probably contains also some amount of nano silica particles which might affect the rheology of cement paste [ 21 , 22 ]. There are two main ways of making a concrete resistant for frost attack.…”

“…This article presents a new way of valorising ilmenite mud waste as an additive to frost resistance concrete. Previous articles [ 21 , 35 ] have shown that ilmenite mud waste might be a useful material as an additive for typical low cost concretes with low compressive class and made from common materials. This article presents the results of tests performed on higher compressive strength classes, which are durable in more extreme environments including frost attack with de-icing salts.…”