Sustainable Gas Separation by Application of Natural Zeolites as Membranes and Adsorbents

• Author / Creator

  Farjoo, Afrooz

• The objective of this research was to develop new molecular sieve materials and to examine their applications in membrane as well as adsorptive gas separation processes. Membrane-based processes have the potential to overcome the limitations of conventional gas separation techniques such as high-energy consumption and environmental concerns. Natural zeolite membranes have recently been shown to demonstrate potential in separation of H2 from H2/CO2 mixtures or H2/Light hydrocarbon mixtures and can be used as a model for development of robust molecular sieve membranes with superior separation characteristics. Recently, disc membranes generated from high purity natural clinoptilolite mineral rock showed promising gas separation performance. In this study a new strategy for scaling up the production of these types of membranes for industrial applications was applied and developed in different configurations such is disk or tubular. The membranes’ permeation, separation performance and separation mechanisms were evaluated using different characterization methods and tests at different conditions. The results showed that natural zeolite membranes such as compact disk or coated stainless steel tubular ones have great potential for large-scale gas separation at high temperature and pressures. To evaluate the potential of membranes in industrial applications, single versus multicomponent gas permeance was compared and discussed. In another study, a new adsorbent for the adsorptive separation of ethylene from ethane as one of the most energy intensive separations was created by incrementally changing the pore size of clinoptilolite. The structure of a naturally occurring clinoptilolite was modified through ammonium exchange, calcination, and post-calcination steam treatment. The results demonstrated the potential to use steamed clinoptilolite to increase the efficiency of the adsorptive separation of ethane and ethylene. Results of this work indicate that natural zeolites can be applied as robust membranes and manipulated as unique adsorbents for enhanced gas separation. With further research, natural zeolites could serve as economically feasible membranes and adsorbents for countless industrial processes.

• Subjects / Keywords

  • Adsorption
  • Zeolites
  • Clinoptilolite
  • Gas separation

• Graduation date

  Fall 2016

• Type of Item

  Thesis

• Degree

  Doctor of Philosophy

• DOI

  https://doi.org/10.7939/R30P0WZ8X

• License

  This thesis is made available by the University of Alberta Libraries with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.