Evaluation of antifoaming behaviour of polysiloxane mixed with fluoroalkyl as antifoam in degraded amine solution

The removal of CO 2 from natural gas by absorption in amine-based solvent is a vital process for oil and gas industries. However, this process frequently struggles to meet its market specifications due to the degradation of amine solution by contaminants in the absorption system which often leads to foam formation and cause issues such as reduction in process performance. The aim of this study is to evaluate the antifoaming performance of Polymethylhydrogensiloxane (PMHS) with Hexafluorobutyl Acrylate (HFBA) antifoam in the methyldiethanolamine (MDEA) and piperazine (PZ) solution degraded by glycine, heptanoic acid and bicine. The antifoaming performance of PMHS + HFBA antifoam in this study has been found to be superior compared to the PDMS antifoam. The highest antifoaming performance for PMHS + HFBA and PDMS antifoam is in the presence of heptanoic acid with the highest average foaming tendency reduction of 61.91 % and 42.39 % respectively. This is attributed to the higher spreading coefficient of PMHS + HFBA antifoam that enables it to rupture foam at a faster rate. This study will demonstrate the importance of the continuous improvement of the use antifoams in reducing foam formation for absorption systems. • The antifoaming performance of PMHS + HFBA and PDMS was evaluated in degraded MDEA + PZ solution. • The higher spreading coefficient of PMHS + HFBA lead to a better antifoaming performance. • PMHS + HFBA antifoam is able to reduce both foam height and foam break time. • PDMS antifoam was merely able to reduce foam height.