No abstract

Emulsion liquid membrane (ELM) has been widely studied as an alternative method for amine absorption technology in the removal of acid gases such as carbon dioxide (CO2) and hydrogen sulphide (H2S). However, searching for stable ELM formulation with an enhanced CO2 absorption remains as challenge. Therefore, in this study, the aqueous solution containing a mixture of methyl diethanolamine (MDEA) and 2-amino-2-methyl-1-propanol (AMP) in sodium hydroxide (NaOH) solution was introduced as a dispersed phase, kerosene as continuous phase and Span-80 acts as a surfactant for the formation of water-in-oil (W/O) emulsion. In this study, the dispersed phase consists of 8% v/v MDEA and 4% v/v AMP and the continuous phase which contains 6% v/v Span-80 produced a stable emulsion and exhibited 65.2% of CO2 removal. This study indicates that the introduction of blended amine able to produce stable emulsion with an enhanced CO2 removal.

Absorption using aqueous alkanolamine is commonly used in industry to remove the carbon dioxide. However it has several weaknesses such as corrosion problem and low absorption rate. Emulsion liquid membrane is introduced as an alternatives method for CO2 absorption because it can reduce the corrosion problem and the formation water droplets creates large interfacial area for absorption to occur. 2-amino-2-methyl-1-propanol (AMP) and monoethanolamine (MEA) present in the aqueous phase in the form of aqueous droplets, surrounded by the organic solution to form water in oil (w/o) emulsion. In this study, effects of amines ratios and amine quantities, and emulsification time and speed on the ELM stability and CO2 absorption were investigated. The ELM was prepared by homogenizing the aqueous and the organic phases. AMP and MEA were added into sodium hydroxide (NaOH) solution to form aqueous solution, and kerosene and Span-80 were mixed to form the organic solution. The absorption study was carried out in rotating disc contactor (RDC) column. A mixture of 12 v% MEA, 4 v% AMP in 100 ml aqueous solution and 8 v% Span-80 in 100 ml organic phase has high stability and can remove 60% of CO2. The stability of the emulsion remained high even after the absorption. This study proved that ELM has the potential to remove CO2 by using only small amount of amines.

Abstract-Emulsion liquid membrane was formulated using MDEA and piperazine as extractant in sodium hydroxide solution. Span-80 in the organic solution acts as surfactant to stabilize the formation emulsion. The effects of MDEA/PZ ratio on emulsion stability and CO 2 absorption were investigated. CO 2 absorption was carried out in rotating disc contactor (RDC) column and gas chromatography (GC) was used to determine the amount of CO 2 leaving the column. This study showed that 8% v/v Span-80 has produced a stable emulsion. The emulsion was able to remove 60.3% of CO 2 . In the presence of methane (CH4), 54.1% of CO 2 and 13.2% of CH4 were removed from CH 4 /CO 2 mixtures. The finding demonstrates the promising technique of ELM for CO 2 removal.

The capture of carbon dioxide (CO2) by aqueous alkanolamine is the most cost effective technology available today. However, some problem such as amine losses, corrosion and low absorption rate arise when aqueous alkanolamines is used as an absorbent. To overcome these problems, liquid emulsion was introduced as an alternative for CO2 removal. However, the main concern of using liquid emulsion is the stability of the emulsion. In this study, a formulation containing mixture of blended alkanolamine was used. Methyldiethanolamine (MDEA) and 2-amino-2-methyl-1-propanol (AMP) were used as extractants and were mixed with sodium hydroxide (NaOH) solution to form the aqueous phase. Meanwhile, the organic phase consists of kerosene and Span 80. The emulsion was prepared by homogenizing both phases at speed of 10 000 rpm for five minutes. The stability of the MDEA-AMP emulsion was determined and the CO2 absorption by the emulsion was measured. This study showed that using 8 mL MDEA and 4mL AMP, the stability of the emulsion was 74.00% and 48.05% of CO2 was removed.