Hydrogenation and Hydrodesulfurization

FEWFEAC323

Program
This project was funded through DOE's Natural Gas and Oil Technology Partnership Program. The program establishes alliances that combine the resources and experience of the nation's petroleum industry with the capabilities of the national laboratories to expedite research, development, and demonstration of advanced technologies for improved natural gas and oil recovery.

Project Goal
The goal is to develop a hydrogenation catalyst capable of operation at moderate or mild conditions.

Performers
Oak Ridge National Laboratory (ORNL)
Oak Ridge, TN

Argonne National Laboratory (ANL)
Argonne, IL

Project Results
A hydrogenation catalyst was developed.

Benefits
The catalyst developed will assist refiners in correcting corrosion problems that occur in heavy oil refining processes.

Background
The processing of heavy oils is currently plagued by two major problems, one involving presence of asphaltenes, which increases oil viscosity; and the second involving the heteroatom content, which poses corrosion and complex refining problems. Technology is needed to process heavy crudes in order to reduce viscosity and heteroatom content under mild conditions. Additions of hydrogen to aromatic and heteroatom molecules via a biological route can be a potentially attractive alternative to upgrading heavy crudes. However, hydrogen addition to molecules existing in petroleum using natural enzymes is difficult.

In order to make the biological enzymes work with compounds in crude oil, it is necessary to create favorable binding interactions between the oil substrates and enzymes. The difficulty in coupling enzymes with the hydrophobic substrates in oil can be overcome by reducing the polarity or increasing the hydrophobicity of the enzyme's substrate docking site. This modification was be done at ORNL. The approach was based on understanding the enzyme-substrate interaction and then modifying the enzyme to improve its activity. The improvements was partly assessed using EXAFS technology in collaboration with ANL. Selected enzyme catalysts were subjected to kinetic testing and thermal stability tests. Industrial input was sought in catalyst development as well as in performing preliminary economic analysis.

Project Summary
The laboratory set-up was updated to carry out anaerobic microbiology and enzymology work for modification of hydrogenase enzymes to be developed into desulfurization biocatalysts. A collaboration was set up with Dr. Mike Adams at the University of Georgia, Athens, GA, to obtain the thermophilic hydrogenase enzyme and to study its activity against organosulfur compounds.

At ANL, catalyst-testing units have been modified for testing of catalyst samples received from ORNL. These units include a plug flow unit that can study supported enzymes and a stirred autoclave for studying unsupported enzymes. The plug flow unit also has a back-mixed reactor cell for studying long-term heterogeneous catalyst synthesis and testing. In-situ EXAFS cells have been modified and tested for collecting data on stream for promising catalyst leads. With this equipment, researchers should be able to tell the coordination sphere and oxidation state of the active metals in time slices as small as one minute under reaction conditions.

Current Status (October 2005)
This project is complete.

Project Start: April 12, 2001
Project End: April 11, 2004

Anticipated DOE Contribution: $625,000
Performer Contribution: $151,000 (20% of total)

Contact Information
NETL - Kathleen Stirling (kathy.stirling@netl.doe.gov or 918-699-2008)
ORNL - Abhijeet Borole (borolea@ornl.gov or 865-576-7421)