Publications

Jan, 2025

Journal

Polymer Layer-Accelerated CO2 Absorption in Aqueous Amino Acid Solutions

Direct air capture (DAC) of CO2 via solvent-based absorption is considered a promising negative-emission technology. However, the low concentration of CO2 in the air and slow transport into the solvent make DAC notoriously challenging to implement without costly investments. In this study, we explore the fundamental role that the bulk and surface properties of CO2-permeabl…

Jan, 2025

Journal

In Silico Screening of CO2-Dipeptide Interactions for Bioinspired Carbon Capture

Carbon capture, sequestration and utilization offers a viable solution for reducing the total amount of atmospheric CO2 concentrations. On an industrial scale, amine-based solvents are extensively employed for CO2 capture through chemisorption. Nevertheless, this method is marked by the high cost associated with solvent regeneration, high vapor pressure, and the corrosive…

Oct, 2024

Journal

Towards Energy-Efficient Direct Air Capture with Photochemically-Driven CO2 Release and Solvent Regeneration

The intensive energy demands associated with solvent regeneration and CO2 release in current direct air capture (DAC) technologies makes their deployment at the massive scales (GtCO2/year) required to positively impact the climate economically unfeasible. This challenge underscores the critical need to develop new DAC processes with significantly reduced energy costs. Rece…

Oct, 2024

Journal

Sub-Ambient Performance of Potassium Sarcosinate for Direct Air Capture Applications: CO2 Flux and Viscosity Measurements

Absorption based direct air capture (DAC) technologies have garnered significant interest in recent years due to their scalability, competitive regeneration energy requirements, and low susceptibility to degradation. One of the key advantages of DAC lies in its flexible siting options and the potential to utilize low-value land. However, most of the research in this field…

Aug, 2024

Journal

Structure of the Bastnäsite (001) Surface by Crystal Truncation Rod X-ray Diffraction and Ab Initio Molecular Dynamics: Implications for Separations of a Rare Earth Ore Mineral

Bastnäsite ((Ce,La)FCO3) is the primary mineral source of light rare earth elements, but its surface structure is not well understood. This presents a major challenge in improving beneficiation strategies. In this work, a synergistic combination of X-ray scattering and ab initio molecular dynamics (AIMD) was used to gain atomistic insight into the interfacial structure of…

Aug, 2024

Journal

Pronounced reduction in the regeneration energy of potassium sarcosinate CO2 capture solvent using TiO2

Absorption-based CO2 capture technologies face economic feasibility concerns due to the exceedingly high energy requirements of solvent regeneration. Among various proposed solutions, solid acid-aided solvent regeneration stands out as a promising approach. Studies have shown that solid materials containing Lewis and Brønsted acid sites can facilitate deprotonation of prot…

Jul, 2024

Journal

Effective direct steam regeneration of bis-iminoguanidine solid sorbent used for carbon dioxide capture

A cost-effective, energy-efficient sorbent regeneration process for phase-changing guanidines used for CO2 capture was developed based on direct-steam stripping. This approach enhances the regeneration rate, simplifies the overall CO2 capture process, and reduces the energy cost compared to conventional conductive thermal regeneration. A direct-steam sorbent regeneration r…

May, 2024

Journal

Direct Air Capture of CO2 via Reactive Crystallization

Atmospheric CO2 removal using engineered chemical processes, aka direct air capture (DAC), has become an essential component of our available portfolio for mitigating climate change. Here we describe a promising approach to DAC based on reactive crystallization of atmospheric CO2 (RC-DAC) with aqueous guanidine and amino acid. Compared to the previously studied phase-chang…

Apr, 2024

ORNL Report

Integrated Process for Direct Air Capture of CO2 and Electrochemical Conversion to Ethanol

Mar, 2024

Journal

Synergistic Assembly of Charged Oligomers and Amino Acids at the Air–Water Interface: An Avenue toward Surface-Directed CO2 Capture

Interfaces are considered a major bottleneck in the capture of CO2 from air. Efforts to design surfaces to enhance CO2 capture probabilities are challenging due to the remarkably poor understanding of chemistry and self-assembly taking place at these interfaces. Here, we leverage surface-specific vibrational spectroscopy, Langmuir trough techniques, and simulations to mech…

Dec, 2023

Journal

Enhancing selectivity of cation exchange with anion receptors

We introduce a new supramolecular strategy where an anion receptor modifies the selectivity ligands for cations. This is demonstrated by combining the classic anion receptor calix[4]pyrrole (C4P) and a phenolic ligand, which leads to remarkable enhancement in selectivity for Cs+ over Na+. Crystal structures and molecular simulations confirmed the persistent formation of io…

Dec, 2023

Journal

Direct Air Capture of CO 2 with Aqueous Amino Acids and Solid Bis-iminoguanidines (BIGs)

We report a bench-scale direct air capture (DAC) process comprising CO2 absorption with aqueous amino acid salts (i.e., potassium glycinate, potassium sarcosinate), followed by room-temperature regeneration of the amino acids by reaction with solid meta-benzene-bis(iminoguanidine) (m-BBIG), resulting in crystallization of the hydrated m-BBIG carbonate salt, (m-BBIGH2)(CO3)…