Simultaneous solidification of two catalyst wastes and their effect on the early stages of cement hydration

Simultaneous Use of Two Catalytic Wastes to Cement in Sustainable Construction Materials

“…Between 200 and 350 o C, thermal decomposition of other hydrated phases occurs. Between 400 and 460 o C, there is the dehydroxylation of the calcium hydroxide [21]. Between 500 and 800 o C the decarbonation of calcium carbonate occurs.…”

“…Through thermal analysis (TG/DTG), it was possible to evaluate the effects of the presence of the wastes on the cement hydration process [10][11][12][13]. The cement matrix performance was also evaluated by X Ray Diffraction [15], leaching [16] and compressive strength [11] tests with solidified samples after 28 days of hydration.…”

A Comparative Study Between the Early Stages Hydration of a High Strength and Sulphate Resistant Portland Cement and the Type II F Portland Cement Through Non Conventional Differential Thermal Analysis and Thermogravimetry

“…These techniques allows to determine the quantitative of the main formed hydration products, to study the effects of different mineral additives, as fly ash, silica fume, for example, by pozzolanic activity [4][5][6] , to determine the carbonation degree of cementitious materials, by the consumption of Ca(OH) 2 and consequently formation of CaCO 3 , as an indicative of durability or quantifying the CO 2 captured in the own matrix 7,8 . The non-conventional differential thermal analysis (NCDTA), different from the differential thermal analysis (DTA), where the thermal effects are measured, by the control of an external heating or cooling device 2,9 , is a system which operates semi-adiabatically allowing to measure, the temperature difference between a sample and an inert reference, as DTA operates, but due to the thermal effects promoted by the spontaneous cement hydration exothermal reactions. The NCDTA has been used in several studies to monitoring, on real time, the hydration reaction, by the water to cement (w/c) ratio variation 2 , the mineral additives in the pozzolanic activity 4 and the use of residues within the cement in a solidification process 9 .…”

“…The non-conventional differential thermal analysis (NCDTA), different from the differential thermal analysis (DTA), where the thermal effects are measured, by the control of an external heating or cooling device 2,9 , is a system which operates semi-adiabatically allowing to measure, the temperature difference between a sample and an inert reference, as DTA operates, but due to the thermal effects promoted by the spontaneous cement hydration exothermal reactions. The NCDTA has been used in several studies to monitoring, on real time, the hydration reaction, by the water to cement (w/c) ratio variation 2 , the mineral additives in the pozzolanic activity 4 and the use of residues within the cement in a solidification process 9 . In this work, the hydration behavior of two types of cement pastes during their first 24h of hydration was evaluated from NCDTA and TG/DTG analysis.…”

Immobilization of Zn(II) in Portland cement pastes

“…Other authors have studied two catalyst wastes from polyol production, which were considered hazardous due to their respective high concentration of nickel and aluminum contents respectively [13]. The paper presents the study carried out to avoid environmental impact, of the simultaneous solidification/stabilization of both catalyst wastes with type II Portland cement with the use of non-conventional differential thermal analysis.…”