Transition metal oxides present in waste incineration systems have the ability to catalyze the formation of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) through surface reactions involving organic dioxin precursors. However, studies have concentrated on the catalytic effects of individual transition metal oxides, while the complex elemental composition of fly ash introduces the possibility of synergistic or inhibiting effects between multiple, catalytically active components. In this study, we have tested fly ash surrogates containing different ratios (by weight) of iron (III) oxide and copper (II) oxide. Such Fe₂O₃/CuO mixed-oxide surrogates (in the Fe:Cu ratio of 1.8, 0.44, and 0.11) were used to study the cooperative effects between two transition metals that are present in high concentrations in most combustion systems and are known to individually catalyze the formation of PCDD/Fs. The presence of both iron and copper oxides increased the oxidative power of the fly ash surrogates in oxygen rich conditions and led to extremely high PCDD/F yields under pyrolytic conditions (up to >5% yield) from 2-monochlorophenol precursor. PCDD/F congener profiles from the mixed oxide samples are similar to results obtained from only CuO, however the total PCDD/F yield increases with increasing Fe₂O₃ content. Careful analysis of the reaction products and changes to the oxidation states of active metals indicate the CuO surface sites are centers for reaction while the Fe₂O₃ is affecting the bonds in CuO and increasing the ability of copper centers to form surface-bound radicals that are precursors to PCDD/Fs.

存在于废物焚烧系统的过渡金属氧化物具有催化多氯代二苯并-的形成的能力p -dioxins和二苯并呋喃通过涉及有机二恶英前体的表面反应（PCDD / FS）。然而，研究集中在单个过渡金属氧化物的催化作用上，而粉煤灰的复杂元素组成引入了在多个催化活性组分之间产生协同或抑制作用的可能性。在这项研究中，我们测试了含有不同比例（按重量计）的氧化铁（III）和氧化铜（II）的粉煤灰替代品。此类Fe ₂ O ₃/ CuO混合氧化物代用品（Fe：Cu比为1.8、0.44和0.11）用于研究大多数燃烧系统中高浓度存在的两种过渡金属之间的协同作用，已知它们分别催化形成PCDD / Fs。铁和铜氧化物的存在增加了在富氧条件下粉煤灰替代物的氧化能力，并导致在热解条件下由2-一氯苯酚前体产生的PCDD / F产率极高（高达5％）。来自混合氧化物样品的PCDD / F同系物分布与仅从CuO获得的结果相似，但是总PCDD / F产率随Fe ₂ O _3的增加而增加内容。对反应产物和活性金属氧化态的仔细分析表明，CuO表面位点是反应中心，而Fe ₂ O ₃影响CuO中的键并增加铜中心形成表面结合自由基的能力。是PCDD / F的前身。