Date of Award

12-2012

Level of Access Assigned by Author

Campus-Only Thesis

Degree Name

Master of Science (MS)

Department

Chemical Engineering

Advisor

William J. DeSisto

Second Committee Member

Clayton M. Wheeler

Third Committee Member

Adriaan R.P. van Heiningen

Abstract

There is currently rising concern about securing sustainable, environmentally friendly and affordable sources of energy. The supply of liquid fuels from petroleum is of particular concern due to increasing demand and dwindling supplies. Biomass is a valuable alternative renewable energy source that can be converted to fuels and chemicals. Biomass currently supplies 14% of the world’s energy needs. Forest biomass is comprised of cellulose, hemicellulose and lignin. Cellulose and hemicellulose are used in pulping industries, however lignin is essentially considered as a waste product, which is burned for energy. Fluidized bed reactor was designed and built for pyrolyzing lignin. Problems faced in conventional fast pyrolysis of lignin, yields and compositions of biooils are compiled. We are introducing a novel green process, Formate Assisted Pyrolysis (FAsP) that is very effective in producing liquid fuels and value-added chemicals from lignin. In this method, lignin is mixed with formate salts and pyrolyzed at 500°C in a fluidized bed reactor. The addition of calcium formate to lignin prior to fast pyrolysis results in deoxyhydrogenation of the lignin during pyrolysis. The calcium formate thermally decomposes in the inert atmosphere to hydrogen and carbon monoxide that facilitates the chemical transformation in-situ. The process occurs at atmospheric pressure and without catalysts. There are several immediate benefits to this method for fast pyrolysis of lignins including improvements in lignin feeding to the pyrolysis reactor, an increase in liquid yield, and an increase in the carbon yield in the oil phase of the liquid product. The primary products of this method are alkylated phenols. GC-MS analysis indicated that methoxy groups were removed from the lignin with the addition of calcium formate. Biooils, which were collected, have very low oxygen content, and high heat values of 41MJ/Kg approaching crude oil. Results from this method will be described, compared with conventional pyrolysis of lignin and evaluated with respect to the advantages relative to competing technologies.

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