Adsorption of Gases and VOCs
Production of Natural Gas from Landfill Gas as a Sustainable Energy Source
Municipal landfills produce methane (CH4) and carbon dioxide (CO2) gases and they need to be separated and removed for 2 reasons. The first is the greenhouse gas reduction. Since CO2 is a green house gas and CH4 has 20 times the greenhouse gas effect as CO2, technologies and techniques to reduce CH4 and CO2 emissions into the atmosphere are of interest. The second is developing a technology to recover both pure CO2 and pure CH4 from the landfill gas streams. The CH4 can be dispensed directly into natural gas pipelines if the purity is high enough and pure CO2 can be obtained for commercial use, enhanced oil recovery or sequestration. So the nature of the problem is to identify an optimal technique (low capital cost, low operating cost) to recover both pure CO2 and CH4 from these gas sources. This project looks at the separation and recovery of CO2 and CH4 from landfill gas by using different adsorbent materials to be used by an adsorption process. The results of this project will help our society to be much more sustainable.
Different graduate and undergraduate students have been working in this area under Dr. Tezel's supervision. These projects include adsorbent screening, and adsorbent tailoring for different separations. Pure and mixture isotherms are determined experimentally. Different adsorption models have been used for the prediction of mixture isotherms and compared to the experimental ones. Modeling of the adsorption process has been carried out for different scenarios. Adsorbents used include ZSM-5, silicalite, Zeolite 4A, Zeolite 5A, Zeolite 13X, erionite,chabazite, clinoptilolite, mordenite, different activated carbons, carbon molecular sieve, activated carbons, AlPO4-11, AlPO4-17, AlPO4-18. Some of these synthetic and natural adsorbents have been modified, ion-exchanged and treated under different conditions to improve the separation before they are used as adsorbent.