| Summary: | Ceramic membrane contactors hold great promise for CO<sub>2</sub> desorption due to their high mass transfer area as well as the favorable characteristics of ceramic materials to resist harsh operating conditions. In this work, a hydrophobic tubular asymmetric alpha-alumina (α-Al<sub>2</sub>O<sub>3</sub>) membrane was prepared by grafting a hexadecyltrimethoxysilane ethanol solution. The hydrophobicity and permeability of the membrane were evaluated in terms of water contact angle and nitrogen (N<sub>2</sub>) flux. The hydrophobic membrane had a water contact angle of ~132° and N<sub>2</sub> flux of 0.967 × 10<sup>−5</sup> mol/(m<sup>2</sup>∙s∙Pa). CO<sub>2</sub> desorption from the aqueous monoethanolamine (MEA) solution was conducted through the hydrophobic tubular ceramic membrane contactor. The effects of operating conditions, such as CO<sub>2</sub> loading, liquid flow rate, liquid temperature and permeate side pressure, on CO<sub>2</sub> desorption flux were investigated. Moreover, the stability of the membrane was evaluated after the immersion of the ceramic membrane in an MEA solution at 373 K for 30 days. It was found that the hydrophobic α-Al<sub>2</sub>O<sub>3</sub> membrane had good stability for CO<sub>2</sub> desorption from the MEA solution, resulting in a <10% reduction of N<sub>2</sub> flux compared to the membrane without MEA immersion.
|
|---|