Effects of Transition Metal Oxide Catalysts on MEA Solvent Regeneration for the Post-Combustion Carbon Capture Process

Abstract

Large heat duty for amine regeneration in absorptionbased CO 2 capture is one of the major drawbacks of this process. Along with a highly endothermic carbamate breakdown reaction in the stripper, the difficulty of proton transfer from protonated amines to water in the amine regeneration process is also considered a basic reason for high heat duty. Transition metal oxide catalysts can play a vital role in decreasing the required thermal energy for amine regeneration in the stripper by providing Bronsted acids and Lewis acids that would help break down the carbamate by direct attack. MEA saturated with CO 2 at 35 °C, with initial loading of 0.56 mole CO 2 /mole amine, was used in this study. The performance of five different transition metal oxide catalysts, V 2 O 5 , MoO 3 , WO 3 , TiO 2 , and Cr 2 O 3 , was studied separately to investigate the effects of these catalysts on amine regeneration in the temperature range of 35−86 °C. It has been observed that MoO 3 performance is much better as it regenerated almost double of the MEA solvent than noncatalytic amine regeneration systems, whereas other catalysts also showed considerable differences in amine regeneration in this temperature range. The amine regeneration performance trend was MoO 3 > V 2 O 5 > Cr 2 O 3 > TiO 2 > WO 3 > blank test. The application of this work would mean that metal oxide catalysts could be used in strippers for a faster CO 2 desorption rate at lower temperature, which would cause a significant reduction of the heat duty.

Catalyst-TiO(OH)2 could drastically reduce the energy consumption of CO2 capture

“…Silica gel with similar particle size and porosity to TiO(OH) 2 barely changes the CO 2 sorption breakthrough profile. Qualitatively consistent with the Bhatti et al work 15 , TiO 2 also barely changes the CO 2 sorption breakthrough curve. Also, recently reported H-ZSM5 13,14 does not change CO 2 breakthrough curve much.…”

“…Idem et al reported that H-ZSM and γ-Al 2 O 3 could be used to accelerate the amine based solvent regeneration and thus reducing the heat duty for amine regeneration 13,14 . Bhatti et al 15 recently reported an inspiring finding that transition metal oxides could affect spent monoethanolamine (MEA) regeneration. Two of those materials, MoO 3 and V 2 O 5 , were found to improve desorption rates substantially because, in fact, they react and dissolve in the CO 2 -rich MEA solvent.…”

Bifunctional Materials for CO₂ Adsorption: Short Review

“…There are several techniques for post combustion CO2 capture such as absorption, adsorption, membrane, and cryogenics [5]- [7]. Absorption technique using aqueous amine, for instance monoethanolamine (MEA), diethanolamine (DEA), and piperazine [8]- [10] has been employed.…”

Study of Catalytic CO2 Absorption and Desorption with Tertiary Amine DEEA and 1DMA-2P with the Aid of Solid Acid and Solid Alkaline Chemicals

“…However, the effects of both solid bases onto a tertiary amine have rarely been discussed either. The effects of solid acid catalysts (γ-Al 2 O 3 , H-ZSM-5, TiO(OH) 2 , and transition metal oxides V 2 O 5 , MoO 3 , WO 3 , TiO 2 , and Cr 2 O 3 ) to MEA [9,21,22,23,24,25] and DEA [26] have also been studied and proven to be effective in the reduction of heat duty. Some studies have been completed to investigate the effects of solid acid catalysts (H-ZSM-5, MCM-41 and SO 4 2− /ZrO 2 ) with blended amine solvents of 5 + 1.0 mol/L MEA-DEEA and MEA-1DMA-2P [9].…”