Lemougna Patrick Ninla, Dilissen Nicole, Hernandez Guillermo Meza, Kingne Felicite, Gu Jun, Rahier Hubert
Department of Materials and Chemistry, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium.
Strategic Initiative Materials in Flanders (SIM), 9052 Zwijnaarde, Belgium.
Materials (Basel). 2021 Sep 23;14(19):5505. doi: 10.3390/ma14195505.
Copper slag (CS) remains a challenging industrial by-product with a relatively small utilization fraction. The present study investigated the development of one-part alkali-activated cements based on CS, ground granulated blast furnace slag (GGBS) and a mixture of the two as a precursor. We investigated 5 to 15 wt% solid sodium metasilicate (NaSiO) and disilicate (NaSiO) as alkaline reagents. Isothermal calorimetry showed that the reactivity of the system was higher for the metasilicate based samples, with early reaction and higher cumulative heat released. Metasilicate based samples also presented a more densified microstructure, lower porosity and higher strength. Better performances were observed with 10 wt% metasilicate/disilicate with respect to the 5 and 15 wt%. The 28-day compressive strength and elastic modulus of 10 wt% metasilicate samples reached 75 MPa and 25 GPa, respectively, and, for paste samples, ranged from 100 wt% GGBS to 50/50 wt% CS/GGBS. The microstructure and calorimetry of the pastes showed that GGBS actively participated in the binding process, whereas CS played a smaller role and acted as a filler and catalyst. The substitution of commercial GGBS by CS up to 50 wt% did not affect the overall performance, thus, bringing CS forward as an economically interesting precursor.
铜渣（CS）仍是一种具有挑战性的工业副产品，其利用率相对较低。本研究调查了基于CS、磨细粒化高炉矿渣（GGBS）以及二者混合物作为前驱体的单组分碱激发水泥的发展情况。我们研究了5至15 wt%的固体偏硅酸钠（NaSiO）和二硅酸钠（NaSiO）作为碱性试剂的情况。等温量热法表明，基于偏硅酸盐的样品体系反应活性更高，反应较早且累积释放热量更高。基于偏硅酸盐的样品还呈现出更致密的微观结构、更低的孔隙率和更高的强度。相对于5 wt%和15 wt%，10 wt%的偏硅酸盐/二硅酸钠表现出更好的性能。10 wt%偏硅酸盐样品的28天抗压强度和弹性模量分别达到75 MPa和25 GPa，对于浆体样品，其范围从100 wt% GGBS到50/50 wt% CS/GGBS。浆体的微观结构和量热法表明，GGBS积极参与了粘结过程，而CS的作用较小，充当填充剂和催化剂。用CS替代高达50 wt%的商业GGBS不会影响整体性能，因此，使CS成为一种在经济上具有吸引力的前驱体。
