Effect of modified Triethanolamine on grinding efficiency and performance of cementitious materials

This paper seeks to improve through esterification the efficiency of triethanolamine (TEA) molecules used in the cement grinding industry. The unmodified and modified-TEAs are tested at 0.025% to 0.1% rates to determine their effect on clinker grindability and cement properties including fineness, flow, zeta potential, morphology, rheology, setting, and compressive strength. Test results showed that the esterification reactions performed to modify the TEA hydroxyl groups can remarkably increase their adsorption potentials onto the clinker grains, which reduces the agglomeration phenomenon and grinding energy consumption by 6% to 13%. The TEA modified using medium hydrocarbon chain lengths (4-8 carbons) of mono-carboxylic acid compounds performed better than the one containing short hydrocarbon chain lengths (1-3 carbons). The pastes and mortars prepared using the modified-TEA cements exhibited significantly higher fluidity, better compatibility with polycarboxylate-based superplasticizer, and increased strengths than the equivalent mixtures made using cement ground using the unmodified TEA molecules.