Accelerated Testing of PEI-Silica Sorbent Pellets for Direct Air Capture.

Amine-based sorbents have shown exceptional CO uptake for direct air capture (DAC). However, amine degradation is a major issue for this class of materials, hindering their deployment for large-scale DAC. In this study, a comprehensive evaluation of polyethylenimine (PEI) sorbents was conducted to understand their degradation under process-relevant environments for the DAC of CO.

Recent Advances in 3D Printing of Structured Materials for Adsorption and Catalysis Applications.

Porous solids in the form of adsorbents and catalysts play a crucial role in various industrially important chemical, energy, and environmental processes. Formulating them into structured configurations is a key step toward their scale up and successful implementation at the industrial level. Additive manufacturing, also known as 3D printing, has emerged as an invaluable platform for shape engineering porous solids and fabricating scalable configurations for use in a wide variety of separation and reaction applications.

Novel Zeolite-5A@MOF-74 Composite Adsorbents with Core-Shell Structure for H Purification.

Hydrogen is considered as one of the most important clean and renewable energy sources for a sustainable energy future. However, its efficient and cost-effective purification still remains challenging. In this work, we report the development of novel zeolite@metal-organic framework (MOF) composites comprised of MOF-74 and zeolite-5A with core-shell structure for efficient purification of H.

3D-Printed Metal-Organic Framework Monoliths for Gas Adsorption Processes.

Metal-organic frameworks (MOFs) have shown promising performance in separation, adsorption, reaction, and storage of various industrial gases; however, their large-scale applications have been hampered by the lack of a proper strategy to formulate them into scalable gas-solid contactors. Herein, we report the fabrication of MOF monoliths using the 3D printing technique and evaluation of their adsorptive performance in CO removal from air. The 3D-printed MOF-74(Ni) and UTSA-16(Co) monoliths with MOF loadings as high as 80 and 85 wt %, respectively, were developed, and their physical and structural properties were characterized and compared with those of MOF powders.

Formulation of Aminosilica Adsorbents into 3D-Printed Monoliths and Evaluation of Their CO Capture Performance.

Amine-based materials have represented themselves as a promising class of CO adsorbents; however, their large-scale implementation requires their formulation into suitable structures. In this study, we report formulation of aminosilica adsorbents into monolithic structures through a three-dimensional (3D) printing technique. In particular, 3D-printed monoliths were fabricated using presynthesized silica-supported tetraethylenepentamine (TEPA) and poly(ethylenimine) (PEI) adsorbents using three different approaches.

3D-Printed Zeolite Monoliths for CO Removal from Enclosed Environments.

Structured adsorbents, especially in the form of monolithic contactors, offer an excellent gas-solid contacting strategy for the development of practical and scalable CO capture technologies. In this study, the fabrication of three-dimensional (3D)-printed 13X and 5A zeolite monoliths with novel structures and their use in CO removal from air are reported. The physical and structural properties of these printed monoliths are evaluated and compared with their powder counterparts.

Aminosilane-Grafted Zirconia-Titiania-Silica Nanoparticles/Torlon Hollow Fiber Composites for CO2 Capture.

In this work, the development of novel binary and ternary oxide/Torlon hollow fiber composites comprising zirconia, titania, and silica as amine supports was demonstrated. The resulting binary (Zr-Si/PAI-HF, Ti-Si/PAI-HF) and ternary (Zr-Ti-Si/PAI-HF) composites were then functionalized with monoamine-, diamine-, and triamine-substituted trialkoxysilanes and were evaluated in CO2 capture. Although the introduction of both Zr and Ti improved the CO2 adsorption capacity relative to that with Si/PAI-HF sorbents, zirconia was found to have a more favorable effect on the CO2 adsorption performance than titania, as previously demonstrated for amine sorbents in the powder form.