Department of Chemical Engineering, Institute of Chemical Technology, Matunga, Mumbai 400019, India.
Department of Chemical Engineering, Institute of Chemical Technology, Matunga, Mumbai 400019, India.
Ultrason Sonochem. 2021 May;73:105547. doi: 10.1016/j.ultsonch.2021.105547. Epub 2021 Apr 1.
TiO catalyst was synthesized in the presence of ultrasound (ultrasonic horn at 20 kHz frequency and 70% duty cycle) at different power (80 W to 120 W) and durations as well as surfactant concentration with an objective of establishing best conditions for achieving lowest particle size of the photocatalyst. Detailed characterization in terms of crystal phase, crystallinity, functional groups and morphology of the photocatalyst has been performed using SEM, XRD and FTIR analysis. It was demonstrated that sonication significantly reduced the particle size with high degree of sphericity and homogeneity as compared to conventionally synthesized TiO with similar crystallinity in both cases. The catalytic performance was subsequently evaluated for the deep desulfurization of thiophene. Different desulfurization approaches including individual US (ultrasonic horn at 20 kHz frequency, 110 W power and 70% duty cycle) and UV irradiations, US/UV, US/UV/HO, US/UV/TiO and US/UV/HO/TiO were applied to evaluate the catalytic activity. The best approach was demonstrated as US/UV/HO/TiO and also activity of catalyst synthesized using ultrasound was much better compared to conventionally synthesized catalyst. The studies related to different model solvents demonstrated lowest reactivity for toluene whereas n-hexane and n-octane resulted in complete desulfurization in 60 min and 50 min treatment respectively. The desulfurization followed pseudo first order reaction kinetics irrespective of the solvent used. Overall the work clearly demonstrated the efficacy of ultrasound in improving the catalyst synthesis as well as desulfurization of thiophene.
TiO 催化剂在超声（20 kHz 频率和 70%占空比的超声喇叭）存在下，在不同的功率（80 W 至 120 W）和持续时间以及表面活性剂浓度下合成，目的是确定实现光催化剂最小粒径的最佳条件。使用 SEM、XRD 和 FTIR 分析对光催化剂的晶体相、结晶度、官能团和形态进行了详细的表征。结果表明，与传统合成的 TiO 相比，超声处理显著降低了粒径，具有高的球形度和均匀性，同时在两种情况下都具有相似的结晶度。随后，对噻吩的深度脱硫进行了催化性能评价。采用不同的脱硫方法，包括单独的 US（20 kHz 频率的超声喇叭、110 W 功率和 70%占空比）和 UV 辐射、US/UV、US/UV/HO、US/UV/TiO 和 US/UV/HO/TiO，评估了催化活性。结果表明，US/UV/HO/TiO 是最佳方法，并且超声合成的催化剂的活性明显优于传统合成的催化剂。与不同模型溶剂相关的研究表明，甲苯的反应性最低，而正己烷和正辛烷分别在 60 分钟和 50 分钟的处理时间内完全脱硫。脱硫遵循拟一级反应动力学，与所使用的溶剂无关。总的来说，这项工作清楚地表明了超声在改善催化剂合成以及噻吩脱硫方面的功效。
