Manufacturing of biocomposite shell mimetic via the powder compaction method
Akter, Taslima
(2006)
Manufacturing of biocomposite shell mimetic via the powder compaction method.
Master of Engineering thesis, Dublin City University.
Natural sea shells are used in the treatment of waste air-streams in biofitration process, however this industry requires new methods of fabricating synthetic shell media to perform in the way natural shell performs. This present study investigates the manufacturing of seashells-like bioceramic/biocomposites as a filter bed with optimum porosity and compressive load capacity using uniaxial die compaction method.
According to the structure of natural sea shell, calcium carbonate bioceramics/biocomposites were designed and manufactured in three steps. In the first step, optimisation of the process parameters and their effects on the porosity (Pr) and compressive load (Cs) of bio-ceramic 1 have been studied. Statistical analyses of the data indicates that only the weight fraction of the pore former and the compaction load influenced significantly the porosity and the compressive load. The compaction speed has no significant influence on the properties of the artificial bioceramic. Higher weight fraction of pore former and lower compaction load leads to high porosity and low compressive load. In the second step, the effect of the particle size of the pore former on porosity and compressive load of calcium carbonate bioceramic 2 was investigated and optimised. The particle size of the pore former has a significant effect on compressive load. No substantial effect of the particle size of the pore former has been found to vary the porosity of the bioceamic 2. In the third step, the effect of the addition of biopolymers on compressive load of calcium carbonate biocomposite has been analysed. The mixing of individual or both biopolymers together increased the compressive load of the calcium carbonate biocomposites significantly.
This new synthetic bioceramic/composites were also examined using X-ray diffraction (XRD), Scanning Electron Microscopy (SEM) and their behaviour under compression test was also determined. Porosity and compressive load of the natural seashells were compared with artificial calcium carbonate bioceramic/biocomposites. The biocomposite performed well mechanically under dry conditions however more research is required to identify the problems that occurred under wet conditions.