Composition for enhancing the thickening time of hematite-based fly ash geopolymers

A hematite-based fly ash composition, comprising:

• a curable component comprising a fly ash binder material (FFA) and a hematite weighting agent present in an amount of 20 to 80% by weight of the fly ash binder material (BWOB);
• one or more superplasticizers (SPs) in an amount of 5 to 10% BWOB;
• one or more retarders in an amount of 5 to 10% BWOB;
• a defoamer in an amount of 0.01 to 0.02% BWOB;
• and
• an aqueous alkaline solution in an amount of 50 to 60% BWOB;
• wherein the hematite-based fly ash composition has a thickening time of from 80 to 580 minutes at 195 degree Fahrenheit (° F.), and a plastic viscosity of 150 to 350 centipoise (cP);
• wherein the FFA comprises 59 to 63 wt. % SiO2, 27 to 31 wt. % Al2O3, 2.5 to 6.5 wt. % Fe2O3, 1 to 4 wt. % K2O, 1 to 3 wt. % TiO2, 0.05 to 0.5 wt. % P2O5, 0.05 to 0.5 wt. % SO3, 0.05 to 0.5 wt. % MgO, each wt. % based on a total weight of the FFA, as determined by X-ray fluorescence (XRF) analysis.