Abstracts Engineering

Laminate zeolite structure prepared using papermaking techniques for carbon dioxide capture: synthesis, characterisation and performance

by Sigappi Narayanan

Carbon capture and storage technology has become a possible solution to address the problem of global warming due to the increasing use of fossil fuels. The application of this technology by many carbon dioxide emitting industrial units is still hindered by the process and equipment cost associated with the capture of carbon dioxide. Zeolites have become a major player in this field due to their high adsorption capacity for carbon dioxide. Traditional use of zeolites in the form of pellets or beads has issues relating to high mass transfer resistance and increased energy consumption required to overcome high pressure drop for such systems. Novel structured adsorbents have been developed to manage these problems but they require high precision and cost for their manufacture. Although they are superior to beads/pellets in terms of breakthrough characteristics, they have very low loading of adsorbent. To overcome the limitations of high cost and low loading of non-particulate structures and the disadvantages of the conventional adsorbent structures, new preparatory techniques for adsorbent structures are being researched. For more practical applications, a zeolite structured adsorbent needs to be created that has high adsorption capacity, low pressure drop, high mass transfer and provides overall high system efficiency. In addition, the very large scale of the flue gas capture application demands that the adsorbent structure should be made using low cost materials and processes. Motivated by the low cost of papermaking technology, we have studied and adapted this technique to create a highly loaded, large surface area sheet structure. Zeolites have already found use in the paper industry as fillers and retention aids and can therefore be easily adapted to current paper mills to create structured laminate adsorbents. This project looks towards creating zeolite laminate structured adsorbent using papermaking techniques for carbon dioxide capture. The selection of materials for the preparation of laminate structures is initially done to create structures that are strong and have high porosity with high loading of zeolite. An easy method of preparing laminate zeolite sheet structures is also outlined. This leads to the next part of the project which is characterisation of the zeolite laminate sheet structures. Although few materials were used in preparation of the sheets, the many variables involved in sheet forming would make it very time consuming to create each unique sheet structure and characterise the properties. Hence, to speed up the process, a partial factorial design method was used to characterise the laminate sheets. 16 experiments were completed. SEM and mercury porosity methods were used to characterise the porosity of the sheet structures. These results show that porosity of the structure is mainly affected by the amount of silica present in the structure. Nitrogen adsorption and carbon dioxide adsorption measurements were studied to determine the loading in the laminate sheet structures, since the adsorption…