摘要
The source of urban atmospheric particles is broad, and the major source is the building dust from urban construction. Calcium is the tagged element and Portland cement is the major com- ponent of building dust. In this study, CaO was regarded as the representative oxide of building dust, and mixtures were synthesized in terms of the major element ingredients of building dust. The het- erogeneous uptake of SO2 on CaO, mixtures, Portland cement and building dust samples was inves- tigated. In situ FTIR and X-ray photoelectron spectroscopy (XPS) were used to identify the products of the reactions. In addition, the crystal phases and the surface properties of the samples were charac- terized by XRD patterns and BET specific surface area. The results show that in the presence of oxygen, sulfur dioxide can be adsorbed to sulfite and further catalytically oxidized to sulfate on the surface of CaO, the mixtures, Portland cement and building dust. The reactivity of SO2 on the surface of dust and oxides is basically a first order. The main ingredient of building dust sample is SiO2, and the one of Portland cement is Ca3SiO5.
The source of urban atmospheric particles is broad, and the major source isthe building dust from urban construction. Calcium is the tagged element and Portland cement is themajor component of building dust. In this study, CaO was regarded as the representative oxide ofbuilding dust, and mixtures were synthesized in terms of the major element ingredients of buildingdust. The heterogeneous uptake of SO_2 on CaO, mixtures, Portland cement and building dust sampleswas investigated. In situ FTIR and X-ray photoelectron spectroscopy (XPS) were used to identify theproducts of the reactions. In addition, the crystal phases and the surface properties of the sampleswere characterized by XRD patterns and BET specific surface area. The results show that in thepresence of oxygen, sulfur dioxide can be adsorbed to sulfite and further catalytically oxidized tosulfate on the surface of CaO, the mixtures, Portland cement and building dust. The reactivity ofSO_2 on the surface of dust and oxides is basically a first order. The main ingredient of buildingdust sample is SiO_2, and the one of Portland cement is Ca_3SiO_5.
基金
This work was supported by the National Natural Science Foundation of China (Grant No. 20377008).
