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The creation of a catalytic method that possesses high activity and effective reusability for the oxidative cleavage of vegetable oils and their derivatives to prepare bio-based oxo-chemicals is a challenge. This work introduces a “release and capture” catalytic system consisting of H2O2, WO3 and mesoporous SnO2. This system was intended to promote catalyst reusability in the oxidative cleavage of methyl 9,10-epoxystearate (ME) to the corresponding aldehydes. No organic solvent was used in the reaction. The reaction temperature, molar ratio of ME/WO3/H2O2, and reaction time were optimized to 70 °C, 1/0.017/1.3, and 20 min, respectively. Under these conditions, complete ME conversion and 80% aldehyde yield were obtained. The hot filtration experiment and ICP-MS analysis confirmed the leaching of tungsten. Mesoporous SnO2 did not affect the ME conversion and aldehyde yield, but effectively adsorbed the leached tungsten. The catalyst in this system showed no significant decrease in activity after being reused ten times. [ABSTRACT FROM AUTHOR]

The oxidative cleavage of vegetable oils and their derivatives to produce bio-based aldehydes is a potentially useful process, although the aldehyde products are readily oxidized to carboxylic acids and thus seldom obtained in high yields. The present study developed a room-temperature method for the synthesis of bio-aldehydes via the oxidative cleavage of vegetable oil-derived epoxides, using H 2 WO 4 as the catalyst, H 2 O 2 as the oxidant, and t -BuOH as the solvent. Reactions were carried out at temperatures ranging from 25 to 35 °C for 3.5-10.5 h, and provided >99% conversion and >90% aldehyde yield. In particular, an approximately 97% yield was obtained at 25 °C after 10.5 h. As the reaction proceeded, the H 2 WO 4 dissolved to form a W-containing anion. Several mesoporous Al-MCM-41 materials having different Si/Al ratios were hydrothermally synthesized and used as adsorbents to recover the catalyst by adsorbing these anions. The adsorption capacity of the Al-MCM-41 was found to increase with decreases in the Si/Al ratio. The Al-MCM-41 had little effect on the oxidative cleavage reaction at 25 °C, and thus could be directly added to the reaction system. The excellent anion adsorption performance of the Al-MCM-41 greatly improved the reusability of the H 2 WO 4 catalyst. When using the Al-MCM-41 with the best adsorption performance, there was no significant decrease in the activity of the catalyst following five reuses., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)