College - Author 1
College of Engineering
Department - Author 1
Materials Engineering Department
Degree Name - Author 1
BS in Materials Engineering
College - Author 2
College of Engineering
Department - Author 2
Materials Engineering Department
Degree - Author 2
BS in Materials Engineering
Date
6-2024
Primary Advisor
Jean Lee, College of Engineering, Materials Engineering Department
Abstract/Summary
The goal of this project was to determine the processing parameters for forming a porous ceramic filter that can function as a longer-lasting alternative to polymer filters used in bioprocessing applications. The ceramic filter targeted the capability to filter out particles 0.5 μm and larger that are suspended in a fluid in a dead-end filtration configuration. Ceramics are an emerging solution for this application because their superior rigidity, high temperature tolerance, and chemical resistance can increase the life span of the filter. Ceramics are typically inert and will not contaminate the filtrate or degrade from moisture, ultraviolet exposure, or other harsh conditions. Ceramic particles of consistent and known size have been mixed with a binding agent and uniaxially pressed into flat circular disks. The ceramic disks have been partially sintered, solidifying the body while leaving open pores throughout the sample. Alumina powder was chosen as the primary ceramic component in these filter prototypes due to its wide availability and biocompatibility. The compaction pressure, sintering temperature, and initial ceramic particle size were varied to study their effects on the filtration performance of these disks. The desired selectivity, porosity, and durability of the disks was evaluated through characterization methods such as filtrate analysis, scanning electron microscopy (SEM), and porosimetry. Challenges with defects in samples led to changes in the sample preparation procedure. A water content of 20 wt%, binder content of 0.5 wt%, and a compaction time of 4 minutes led to intact membranes ~30% of the time. The membranes appeared to have a pore size close to 0.5 mm and porosities around 50%. No trends in pore size or porosity were observed across sintering temperatures. Results from flow testing samples showed that the water flow rate through the ceramic filters was inversely related to the compaction pressure with which the filters were made, and that the ceramic filters appeared to reduce the particle size of filtrate solutions.
URL: https://digitalcommons.calpoly.edu/matesp/279