Effects of Alkanolamine Absorbents in Integrated Absorption–Mineralization

Abstract

Integrated absorption–mineralization (IAM) involves the transformation of CO2 in a chemical-based solution with brine used as the absorbent to form insoluble carbonates and is promising for carbon capture, utilization, and storage. Various types of absorbents such as monoethanolamine (MEA), diethanolamine (DEA), triethanolamine (TEA), and aminomethyl propanol (AMP) were examined in multicycle integrated absorption–mineralization (multicycle IAM) involving absorption, precipitation, and regeneration steps between 20 °C and 25 °C at atmospheric pressure in order to reveal their performance in terms of CO2 absorption and conversion and absorbent degradation. We found that 5 wt.% AMP offered 89.5% CO2 absorption capacity per unit of absorbent converted into the amount of solid carbonate within 4 cycles. In addition, it was moderately degraded by 64.02% during the first cycle and then reduced from 30% to 10% in the next cycle (>2 cycles). In comparison with MEA, which was used as the initial absorbent, AMP provided a fivefold increase in the speed of multicycle IAM.