Acta Chimica Sinica ›› 2014, Vol. 72 ›› Issue (1): 105-113.DOI: 10.6023/A13080905 Previous Articles     Next Articles



于凤丽, 王睿   

  1. 山东大学环境科学与工程学院 济南 250100
  • 投稿日期:2014-08-29 发布日期:2013-11-14
  • 通讯作者: 王睿,;Tel.:0531-88366367
  • 基金资助:

    项目受国家自然科学基金(Nos. 20976097,21076116,21211120165,21311120297);中国石油天然气集团公司石油科技创新基金(2010D-5006-0405)和山东省自然科学基金(ZR2011BM023)资助.

Study on Oxidative Desulfurization Catalyzed by Organic-inorganic Heteropolyacids as Phase Transfer Catalyst

Yu Fengli, Wang Rui   

  1. School of Environmental Science and Engineering, Shandong University, Jinan 250100
  • Received:2014-08-29 Published:2013-11-14
  • Supported by:

    Project supported by the National Natural Science Foundation of China (Nos. 20976097, 21076116, 21211120165, 21311120297), Petro China Scientific and Technical Innovation Project (2010D-5006-0405) and Natural Science Foundation of Shandong Province (ZR2011BM023).

In this paper, organic-inorganic heteropolyacids were prepared, including [π-C5H5NC16H33]3[PW4O16], [π-C5H5NC16H33]3[PMo4O16], [π-C5H5NC12H25]3[PW4O16] and [π-C5H5NC12H25]3[PMo4O16]. The efficiency of oxidative desulfurization was investigated on the four kinds of catalysts under the same conditions using the simulated oil prepared by dissolving organo-sulfur in normal octane. The results show that the catalytic activity of [π-C5H5NC16 H33]3[PW4O16] is the best. The catalytic activity of these heteropolyacids was following the order of [π-C5H5NC16H33]3[PW4O16]>[π-C5H5NC12H25]3[PW4O16]>[π-C5H5NC16H33]3[PMo4O16]>[π-C5H5NC12H25]3[PMo4O16]. Under the optimal experimental conditions, pre-reaction time between H2O2 and the catalyst being 10 min, reaction temperature being 60 ℃, O/S molar ratio being 10, the amount of catalyst being 1 wt% of n-octane, and the catalyst being [π-C5H5NC16H33]3[PW4O16], the dibenzothiophene (DBT) conversion was nearly 100% after 60 min. The catalyst [π-C5H5NC16H33]3[PW4O16] can be reclaimed by auto precipitation due to the exhausting of H2O2. The results show that organic-inorganic heteropolyacids are phase transfer catalyst and oxidative desulfurization system belongs to the phase transfer catalysis system controlled by reaction. The catalytic activity of the recycled [π-C5H5NC16H33]3[PW4O16] is almost the same as the fresh. Then, the efficiency of oxidative desulfurization was investigated with different simulated oils using DBT, thiophene (TH), benzothiophene (BT) and 4,6-dimethyldibenzothiophene (4,6-DMDBT), respectively. Under the same conditions, the efficiencies of oxidative desulfurization decrease in the order of DBT>4,6-DMDBT>BT>TH, the result was influenced by electron density on the sulfur atoms and the steric hindrance. It showed that the final desulfurization product of TH, BT, DBT and 4,6-DMDBT was SO42-,SO42-, DBT sulphone and 4,6-DMDBT sulphone, respectively. [π-C5H5NC16H33]3[PW4O16] used in desulfurization of the real diesel and the sulfur removal rate was 92.7%. The sulfur content was reduced from 355 mg/kg to 26 mg/kg. Furthermore, by studying the kinetics of DBT oxidation by H2O2, the reaction order was found to be 1st to DBT. The activation energy ranged from 47.9 kJ/mol to 55.4 kJ/mol by different organic-inorganic heteropolyacids. It indicates the reaction process is quite fast in ODS. The new type of catalysts has a broad development prospect in oil desulfurization.

Key words: organo-sulfur, oxidative desulfurization, organic-inorganic heteropolyacid, phase transfer catalyst