Effects of sonication on co-precipitation synthesis and activity of copper manganese oxide catalyst to remove methane and sulphur dioxide gases

Yeow Hong Yap; Mitchell S W Lim; Zheng Yee Lee; Kar Chiew Lai; Muhamad Ashraf Jamaal; Farng Hui Wong; Hoon Kiat Ng; Siew Shee Lim; T Joyce Tiong

doi:10.1016/j.ultsonch.2017.06.032

Effects of sonication on co-precipitation synthesis and activity of copper manganese oxide catalyst to remove methane and sulphur dioxide gases

Ultrason Sonochem. 2018 Jan;40(Pt A):57-67. doi: 10.1016/j.ultsonch.2017.06.032. Epub 2017 Jul 1.

Authors

Yeow Hong Yap¹, Mitchell S W Lim², Zheng Yee Lee², Kar Chiew Lai², Muhamad Ashraf Jamaal², Farng Hui Wong¹, Hoon Kiat Ng³, Siew Shee Lim², T Joyce Tiong⁴

Affiliations

¹ Department of Chemical Engineering, Lee Kong Chian Faculty of Engineering, Universiti Tunku Abdul Rahman, Jalan Sungai Long, 43000 Kajang, Selangor, Malaysia.
² Department of Chemical and Environmental Engineering, University of Nottingham Malaysia Campus, Jalan Broga, 43500 Semenyih, Selangor, Malaysia.
³ Department of Mechanical, Materials and Manufacturing Engineering, University of Nottingham Malaysia Campus, Jalan Broga, 43500 Semenyih, Selangor, Malaysia.
⁴ Department of Chemical and Environmental Engineering, University of Nottingham Malaysia Campus, Jalan Broga, 43500 Semenyih, Selangor, Malaysia. Electronic address: joyce.tiong@nottingham.edu.my.

PMID: 28946460
DOI: 10.1016/j.ultsonch.2017.06.032

Abstract

The utilisation of ultrasound in chemical preparation has been the focus of intense study in various fields, including materials science and engineering. This paper presents a novel method of synthesising the copper-manganese oxide (Hopcalite) catalyst that is used for the removal of volatile organic compounds and greenhouse gases like carbon monoxide. Several samples prepared under different conditions, with and without ultrasound, were subjected to a series of characterisation tests such as XRD, BET, FE-SEM, EDX, TPR-H₂, TGA and FT-IR in order to establish their chemical and physical properties. A series of catalytic tests using a micro-reactor were subsequently performed on the samples in order to substantiate the aforementioned properties by analysing their ability to oxidise compressed natural gas (CNG), containing methane and sulphur dioxide. Results showed that ultrasonic irradiation of the catalyst led to observable alterations in its morphology: surfaces of the particles were noticeably smoothed and an increased in amorphicity was detected. Furthermore, ultrasonic irradiation has shown to enhance the catalytic activity of Hopcalite, achieving a higher conversion of methane relative to non-sonicated samples. Varying the ultrasonic intensity also produced appreciable effects, whereby an increase in intensity results in a higher conversion rate. The catalyst sonicated at the highest intensity of 29.7W/cm² has a methane conversion rate of 13.5% at 400°C, which was the highest among all the samples tested.

Keywords: Co-precipitation; Copper manganese oxide; Methane oxidation; Sonochemical synthesis; Ultrasound.