Effect of Monoethanolamine Concentration on CO2 Removal using Continuous High Frequency Ultrasonic ReactorSiti Munirah Mhd Yusof, Azmi Mohd Sharif, Tay Wee Horng, Farhana Ajua Mustafa and Lau Kok KeongE3S Web Conf., 287 (2021) 01001DOI: https://doi.org/10.1051/e3sconf/202128701001