Zhang Xuan, Deng Bin, Sun Tong, Li Wei, Duan Chang-Ping
College of Chemistry, Chemical Engineering and Food Safety, Bohai University, Jinzhou, 121013, People's Republic of China.
Jinzhou Petrochemical Engineering Company, Jinzhou, 121001, People's Republic of China.
Nanoscale Res Lett. 2017 Dec;12(1):392. doi: 10.1186/s11671-017-2160-3. Epub 2017 Jun 8.
Alumina nanorods were prepared from chromium-containing alumina sludge, and the effects of doping elements, such as Cr, Fe, and Mg, were researched. The results show that the crystal transformation of alumina is restricted by the doped Cr and facilitated by the doped Fe and Mg, which is transformed from θ-AlO to α-AlO in the calcination process. Meanwhile, the crystal transformation of alumina is strongly restrained by co-doped elements from the chromium-containing alumina sludge. The doped elements change the course of phase structure transformation and slightly transform the chemical bond of the alumina nanorods. The impure elements are doped in the alumina crystal and restrain the crystalline growth of alumina nanorods according to the rules. In the sample prepared from chromium-containing alumina sludge, more Cr and Mg but fewer Fe are doped, and most Cr are existed as Cr(III). It is possible that the Fe-doping is confined by the competition of Cr and Mg. Moreover, the lattice imperfection of alumina is caused by doped ions, such as Cr, Fe, and Mg, and the chemical state of O and Al are affected. The findings by these experiments provide essential information for eliminating pollution and promoting comprehensive utilization of the chromium-containing alumina sludge.
采用含铬氧化铝污泥制备了氧化铝纳米棒，并研究了Cr、Fe和Mg等掺杂元素的影响。结果表明，掺杂的Cr抑制了氧化铝的晶型转变，而掺杂的Fe和Mg促进了晶型转变，在煅烧过程中氧化铝从θ-AlO转变为α-AlO。同时，含铬氧化铝污泥中的共掺杂元素强烈抑制了氧化铝的晶型转变。掺杂元素改变了相结构转变过程，并使氧化铝纳米棒的化学键略有变化。杂质元素按规律掺杂在氧化铝晶体中，抑制了氧化铝纳米棒的晶体生长。在由含铬氧化铝污泥制备的样品中，掺杂了较多的Cr和Mg，而Fe较少，且大部分Cr以Cr(III)形式存在。Fe掺杂可能受到Cr和Mg竞争的限制。此外，Cr、Fe和Mg等掺杂离子导致了氧化铝的晶格缺陷，并影响了O和Al的化学状态。这些实验结果为消除污染和促进含铬氧化铝污泥的综合利用提供了重要信息。
