Vol.:(0123456789) Research on Chemical Intermediates https://doi.org/10.1007/s11164-019-04016-7 1 3 One‑pot co‑precipitation of copper–manganese–zinc oxide catalysts for the oxidation of CO and SO 2 in the presence of ultrasonic irradiation Jin Kiat Chu 1  · Mitchell S. W. Lim 1  · T. Joyce Tiong 1  · Yeow Hong Yap 2  · Li Yan Lim 1  · Pricella S. J. Yeoh 1  · Kavin Kumar 1  · Siewhui Chong 1  · Yi Jing Chan 1  · Guan‑Ting Pan 3  · Thomas C. K. Yang 3 Received: 3 September 2019 / Accepted: 9 September 2019 © Springer Nature B.V. 2019 Abstract This paper studies the efect of addition of Zn and ultrasound-assisted co-precip- itation on Cu-Mn oxide catalysts for the oxidation of CO. Cu-Mn-Zn oxide cata- lysts were synthesised at diferent molar ratios and characterised and evaluated for CO oxidation performance. Scanning electron microscopy (SEM) imaging showed that the morphologies and textural properties of the catalysts were markedly afected by the diferent synthesis conditions, notably the formation of diferent geom- etries of various sizes depending on the Zn loading used. Characterisation results also revealed that both the addition of Zn and the use of ultrasound-assisted syn- thesis improved the dispersion of metal constituents in the mixed oxide phase, evi- dent from the lower peak intensity and smaller crystallite sizes and more dispersed particles as seen in SEM imaging. Gas adsorption results revealed that Zn loading infuences the porosity and adsorption capability of the catalyst. Zn-loaded sam- ples exhibited a H3 hysteresis loop, which suggests the presence of slit-like pores. Temperature-programmed reduction results indicate that sonicated samples exhibit improved reduction capabilities which can increase overall catalytic activity. Results showed that Cu/Mn/Zn = 2:1:0.5 displayed the highest activity, showing 76.0% and 82.8% for CO and SO 2 at 130 °C, respectively. This work has confrmed that the addition of 0.5 molar ratio of Zn and the presence of ultrasonic treatment during the catalyst synthesis have improved the overall catalytic performance, while further addition in Zn concentrations resulted in an adverse efect on the catalyst. Keywords Copper manganese · Ultrasound · Sonocatalysis · Carbon monoxide · Sulphur dioxide · Zinc oxide * T. Joyce Tiong joyce.tiong@nottingham.edu.my * Thomas C. K. Yang ckyang@mail.ntut.edu.tw Extended author information available on the last page of the article