title: Possible mechanism of structural incorporation of Al into diatomite during the deposition process I. Via a condensation reaction of hydroxyl groups.
abstract: The structural incorporation of aluminium (Al) into diatomite is investigated by preparing several Al-diatomite composites by loading an Al precursor, hydroxyl aluminum polymer (Al13), onto the surface of diatomite and heating at various temperatures. The results indicate that Al was incorporated and implanted into the structure of diatomite by the condensation reaction of the hydroxyl groups of Al13 and diatomite, and the Si-O-Al(OH) groups were formed during the condensation reaction. Al incorporation by the condensation reaction of hydroxyl groups of Al13 with single silanols of diatomite occurred more readily than that with geminal silanols. The Al incorporation increased solid acidity of diatomite after Al incorporation. The acidity improvement was various for different types of acid sites, depending on the preparation temperature of the Al-incorporated diatomite. Both Brønsted and Lewis acid sites increased greatly after heating at 250 and 350 °C, but only L acid sites significantly improved after heating at 500 °C. These results demonstrate that the structural incorporation of Al(3+) ions into diatomite can occur by the condensation reaction of the hydroxyl groups of the Al precursors and diatomite. Moreover, the rich solid acid sites of Al-incorporated diatomite show its promising application as a solid acid catalyst.
authors.affiliation: CAS Key Laboratory of Mineralogy and Metallogeny, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; Guangdong Provincial Key Laboratory of Mineral Physics and Materials, Wushan, Guangzhou 510640, China.
authors.forename: Dong
authors.initials: D
authors.lastname: Liu
authors.affiliation: CAS Key Laboratory of Mineralogy and Metallogeny, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; Guangdong Provincial Key Laboratory of Mineral Physics and Materials, Wushan, Guangzhou 510640, China; Graduate School of Chinese Academy of Sciences, Beijing 100049, China.
authors.forename: Wenbin
authors.initials: W
authors.lastname: Yu
authors.affiliation: CAS Key Laboratory of Mineralogy and Metallogeny, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; Guangdong Provincial Key Laboratory of Mineral Physics and Materials, Wushan, Guangzhou 510640, China; Graduate School of Chinese Academy of Sciences, Beijing 100049, China.
authors.forename: Liangliang
authors.initials: L
authors.lastname: Deng
authors.affiliation: CAS Key Laboratory of Mineralogy and Metallogeny, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; Guangdong Provincial Key Laboratory of Mineral Physics and Materials, Wushan, Guangzhou 510640, China; Graduate School of Chinese Academy of Sciences, Beijing 100049, China.
authors.forename: Weiwei
authors.initials: W
authors.lastname: Yuan
authors.affiliation: CAS Key Laboratory of Mineralogy and Metallogeny, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; Guangdong Provincial Key Laboratory of Mineral Physics and Materials, Wushan, Guangzhou 510640, China; Graduate School of Chinese Academy of Sciences, Beijing 100049, China.
authors.forename: Lingya
authors.initials: L
authors.lastname: Ma
authors.affiliation: CAS Key Laboratory of Mineralogy and Metallogeny, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; Guangdong Provincial Key Laboratory of Mineral Physics and Materials, Wushan, Guangzhou 510640, China. Electronic address: yuanpeng@gig.ac.cn.
authors.forename: Peng
authors.initials: P
authors.lastname: Yuan
authors.affiliation: CAS Key Laboratory of Mineralogy and Metallogeny, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; Guangdong Provincial Key Laboratory of Mineral Physics and Materials, Wushan, Guangzhou 510640, China; Graduate School of Chinese Academy of Sciences, Beijing 100049, China.
authors.forename: Peixin
authors.initials: P
authors.lastname: Du
authors.affiliation: CAS Key Laboratory of Mineralogy and Metallogeny, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; Guangdong Provincial Key Laboratory of Mineral Physics and Materials, Wushan, Guangzhou 510640, China.
authors.forename: Hongping
authors.initials: H
authors.lastname: He
mesh_terms: D000535:Aluminum / Q000737:chemistry*; D007692:Diatomaceous Earth / Q000737:chemistry*; D006878:Hydroxides / Q000737:chemistry*; D015394:Molecular Structure; D012822:Silicon Dioxide / Q000737:chemistry*; D013499:Surface Properties; D013696:Temperature
chemical_list: D006878:Hydroxides; D007692:Diatomaceous Earth; C033787:diatomite; D012822:Silicon Dioxide; C031356:hydroxide ion; D000535:Aluminum
keywords: Al incorporation; Al(13); Diatomite; Solid acidity