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Responding to the strategy of sustainable development, Cement manufacturing industry become an effective method to dispose municipal solid waste (MSW). Zinc is a heavy metal element that might be introduced by industrial wastes to the cement kilns, resulting in a performance degradation. High-Ferrite Cement (HFC), as a kind of sulphate-resistant Portland cement has attracted extensive interesting. Different from the mineral composition of Portland cement, HFC have a low C3S and high C4AF, which may be have a better solidification capacity due to the content increase of solid solution C4AF. This study attempt to explore the influence of doping ZnO on the performance of HFC. The results indicated that the compressive strength of 28 days increased from 57.1 to 70.3 MPa when the content of doping ZnO reached 1.5 wt% and hydration reactivity increased with the increase of ZnO content. The reason could be ascribed to the decrease of retardation effect on C3S and increase of promotion effect on C4AF with the change of miner composition of cement clinker. Beyond that, promotion plays a pivotal role between the two factors. The mechanism analysis indicated that ZnO doping promoted the transformation of Fe in the C4AF from [FeO4] to [FeO6] and increased the effective charge, resulting in a higher hydration reactivity. The result obtained varied from that reported in previous researches, and proved out that HFC can be a good material to Zn solidification/stabilization. |
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