Session: 13-02: Carbon Capture & Cleaner Fossil Fuel Technologies

Paper Number: 141869

141869 - Yeast Engineered Porous 13x Adsorbent Layers Through Freeze-Drying for Co2 Capture 

Abstract: 

This study investigates a novel environmentally friendly coating technique using a yeast fermentation process to obtain super porous Zeolite 13X adsorbent layers through the freeze-drying technique for CO₂ capture applications. Worked with various mass ratios of sugar to yeast to control the porosity and pore sizes in the adsorbent layer. A unique peeling process was integrated to obtain foamy, hollow structures to have deeper layer accessibility of adsorbent for adsorption applications. These coated adsorbent layers were experimentally characterized as a function of the mass ratio of sugar to yeast and adsorbent solid fraction. Scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and Fourier-transform infrared spectroscopy (FT-IR) are used to analyze the coated layers. The void fraction for coated samples is found to vary between 0.48 to 0.56, making the samples applicable for adsorption applications. Adsorption performance experiments are performed to test the coated sample performance compared to 13X powder. Due to their simplistic fabrication, cost-effectiveness, rapid pore formation, and high adsorption capacity, these porous 13X layers hold potential for large-scale fabrication and application in CO₂ capture applications.

This approach, inspired by yeast fermentation, involves adding different mass ratios of sugar to yeast to the 13X adsorbent and xanthan gum binder in a slurry. After conducting numerous preliminary experiments, an optimized coating process was developed, resulting in highly porous and robust adsorbent layers. Importantly, this process offers control over porosity and pore size. To address brittleness and ensure resilience under low temperatures, plexiglass was chosen as the substrate for its cost-effectiveness, widespread availability, and capacity to endure cryogenic conditions, unlike materials such as carbon steel, plastic, and rubber. Zeolite 13X was chosen due to its commercial availability at a low cost and its remarkable adsorption capacity under moderate operating conditions (0-100°C & 0.1-1 bar). Yeast, the common cooking ingredient used to make bread rise, breaks down sugar for energy through respiration. The carbon dioxide bubbles generated serve to create voids in the adsorbent layer, forming porous pockets. These voids play a crucial role in the microchannel bed design, allowing access to the adsorbent particles deeper within the layer. Voids create additional surface area and accessibility within the adsorbent structure, providing more sites for CO₂ molecules to adhere to. 

Coated samples with a 23% solid fraction in a 1/2 mass ratio of sugar to yeast showed significant adsorbent presence, confirmed by SEM, EDX, and FT-IR analyses. EDX illustrated accessible adsorbent particles hanging onto the sample's void structure, while FT-IR indicated retained and accessible adsorbent with varying peak intensities. Equilibrium pressure durations range from 25 to 30 minutes for 13X powder and 30 to 55 minutes for coated samples, depending on the mass ratio of sugar to yeast. Higher yeast content leads to larger void sizes and longer equilibrium times. The 1/2 mass ratio appears optimal, achieving 96% of the powder's capacity in around 40 minutes. Despite longer equilibrium times, the 1/3 mass ratio exhibits the highest adsorption capacity, nearly equivalent to 13X powder, owing to a higher amount of adsorbent within coated layers. This underscores the efficiency of the developed coating technique utilizing yeast, sugar, and xanthan gum, which establishes a uniform, hollow, flexible, robust, and super-porous structure on the plexiglass substrate, surpassing existing coating methods in reliability and adsorbent structure.

A pioneering coating technique employing biological ingredients has been devised to fabricate Zeolite 13X adsorbent-based microchannels for CO₂ adsorption processes. The coating procedure can be replicated with any adsorbent, yielding porous adsorbent layers. Utilizing biological ingredients entails reduced environmental impact, rendering it the optimal choice for sustainability. Three distinct mass ratios (ranging from 1/1 to 1/3) of sugar to yeast, spanning from 12% to 25% of the 13X adsorbent solid fractions within each ratio, were integrated into an adsorbent slurry mixed with yeast, sugar, and xanthan gum. The adoption of this method shows considerable potential for fabricating adsorbent beds tailored for conducting future CO₂ breakthrough experiments.

 

Presenting Author: Mary Sharon Rose Bondugula Florida Institute of Technology

Presenting Author Biography: Sharon graduated with a Bachelor of Technology in Aerospace Engineering from Karunya Institute of Technology & Sciences, India, and a Master of Science in Space Engineering from Politecnico di Milano, Italy. During her bachelor's and master's programs, she worked on ignition delay studies of hydrocarbon fuels using shock tubes and hydrogen-based green propellants for future space propulsion applications. Her interest in propulsion led her to publish four papers in the electric and chemical propulsion domain. She worked with the space business operations department of DZH Dynamics in Spain and as a project analyst in Milan, Italy. Not afraid to take risks, she decided to change tracks and pursue her Ph.D. in Mechanical Engineering at Florida Tech, working on thermal energy and fluid flow. She is driven by a desire to contribute to advancing sustainable energy solutions and address the challenges of climate change. She explores novel carbon dioxide capture technologies using adsorption and demonstrates their operation using computational and experimental techniques.

Authors:

Mary Sharon Rose Bondugula Florida Institute of Technology
Kaleem Marc Anthony Bocus Florida Institute of Technology
Nashaita Patrawalla Florida Institute of Technology
Adam Scannell Florida Institute of Technology
Vipuil Kishore Florida Institute of Technolgy
Toufiq Reza Florida Institute of Technology
Darshan Pahinkar Florida Institute of Technology