# Densities of CO2‑Loaded and Unloaded 3‑Amino-1-propanol Aqueous Solutions and Their Blends with 2‑Amino-2-methyl-1-propanol at High Pressures

## TL;DR

This paper reports on the density behavior of CO2-loaded and unloaded amine solutions under high pressure, aiding in carbon capture technologies.

## Contribution

New experimental density data for CO2-loaded and unloaded amine blends under high pressure and temperature are presented.

## Key findings

- Density increased with pressure and decreased with temperature for all tested amine solutions.
- CO2 loading increased density and decreased thermal expansion coefficients.
- Corrosion potential was identified in AP + AMP blends and CO2-loaded solutions.

## Abstract

Carbon capture and storage and carbon capture and utilization
are
key technologies to reduce CO2 emissions by capturing and
storing (or converting) CO2. In this context, amine-based
aqueous solutions play a key role in these processes, especially because
of their efficiency in chemically binding CO2. However,
some physical properties under high pressure and temperature systems
remain poorly reported in physical chemical databases. This work presents
experimental data on the density of aqueous amine solutions of 3-amino-1-propanol
(AP) when they are CO2-loaded and unloaded and its blends
with 2-amino-2-methyl-1-propanol (AMP) (unloaded) under high-pressure
conditions (up to 100 MPa) and at a wide temperature range (293.15–393.15
K). Density measurements were performed using a vibrating tube densimeter
(Anton Paar DMA HPM), and data were correlated with a modified Tammann–Tait
equation, resulting in excellent correlation. These results served
as the support information for estimation of molar volumes and isothermal
expansion coefficients. Overall, density increased with pressure and
decreased with temperature for all amine solutions tested. At low
AP concentrations, a local minimum was observed for the isothermal
expansion coefficient, which is probably attributed to anomalous water
compressibility. Additionally, the CO2 loading led to an
increase in density and a decrease in thermal expansion coefficients.
Finally, elemental analysis revealed a possible corrosion, especially
in blends of AP + AMP and CO2-loaded solutions, providing
valuable insights for material selection and process design.