Abstract: A series of iron-, copper-, zinc-, cerium-, magnesium- and aluminum-containing ternary and quaternary hydrotalcite-like compounds were prepared by coprecipitation and characterized by XRD and N₂ adsorption-desorption.All samples prepared were calcined at 700℃ for 6 h to obtain metal complex oxides whose structure and SO₂ redox performance were measured in a modified WRP-3 thermal balance.The results showed that zinc was not effective for redox of SO₂ and copper was an efficient promoter for oxidization of SO₂ to SO₃, while iron could play dual role of oxidizing and reducing promoter.In quaternary hydrotalcite-like compounds MgAlFeCu(n(Mg²⁺)/n(Al³⁺)=3, m(Fe)=8%, m(Cu)=1%) showed synergistic effect between Fe and Cu, which resulted in its higher oxidative adsorption rate, larger adsorption capacity and better reductive ability, and its total saturation adsorption capacity could be 1.33 g·g^-1 in 6 min.

Key words: sulfur transfer catalyst, hydrotalcite-like compounds, metal complex oxides, oxidative adsorption, reductive desorption

摘要： 采用共沉淀法制备三元类水滑石MgAlX(X=Fe、Cu、Zn)和四元类水滑石MgAlFeX(X=Zn、Ce、Cu),经700℃焙烧6 h后制备了含有不同金属元素的FCC硫转移剂。通过XRD、氮吸附以及改装的WRP-3热重天平对硫转移剂的结构和SO₂氧化还原性能进行表征。结果表明,引入不同金属元素均可以得到结构规整的三元、四元类水滑石前驱体,经过焙烧后得到复合氧化物。三元类水滑石中Zn不具有促进硫转移剂的氧化还原性能,Fe可作为硫转移剂的氧化还原促进剂,Cu可作为优良的氧化促进剂。与MgAlFeZn和MgAlFeCe相比,四元类水滑石MgAlFeCu(n(Mg²⁺)/n(Al³⁺)=3,m(Fe)=8%,m(Cu)=1%)中Fe和Cu协同作用,使其饱和硫容、氧化吸硫和还原脱硫的性能均有所提高,6 min达到饱和硫容1.33 g·g^-1,同时具有较强的还原能力。

关键词: 硫转移剂, 类水滑石, 复合氧化物, 氧化吸硫, 还原脱硫