Final Report: Nearcritical Water For Environmentally Benign Chemical ProcessingEPA Grant Number: R825325
Title: Nearcritical Water For Environmentally Benign Chemical Processing
Investigators: Eckert, Charles A. , Liotta, C. L.
Institution: Duke University
EPA Project Officer: Karn, Barbara
Project Period: October 1, 1996 through September 30, 1999
Project Amount: $180,000
RFA: Technology for a Sustainable Environment (1996) RFA Text | Recipients Lists
Research Category: Sustainability , Pollution Prevention/Sustainable Development
Objective:The specific goals of this project were to determine reaction kinetics and equilibria, and phase equilibria in high-temperature water for pollution prevention and the development of sustainable industrial processes. This work also impacts a much broader scientific area. The phase equilibria of organic/water systems are necessary measurements for refining, tertiary oil recovery, and geology. On an even more profound level, the conditions for reactions in near-critical water are similar to the environment of geothermal vents of the floor of the deep ocean. The unusual chemistry, biochemistry, and biology of these deep ocean vents may be representative of the earth's environment millions of years ago and are of considerable interest to scientists who study the origin(s) of life.
Considerable technical challenges exist for the engineering of chemical manufacturing with environmentally benign solvents. This project provides the basis for adapting a variety of chemical processes to near-critical water as that benign solvent. Water in the range of 250-300?C offers very significant engineering advantages?it dissolves both organics and salts, and so makes normally heterogeneous reactions homogeneous; and it acts as a natural acid and base, orders of magnitude stronger than ambient water, so no added acids (or bases) are required for many reactions, and there is no subsequent need for neutralization and salt disposal. Moreover, in most typical reaction processes, the separation accounts for 60-80 percent of the capital and operating costs. With organic reactions in near-critical water, the separation can be as simple as mere cooling and decanting.
This project supported the research activities of a total of eight undergraduate and Ph.D. students, and one Postdoctoral Visiting Fellow in both Chemical Engineering and Chemistry. Five of these individuals have completed their studies during this project, including:
Karen Chandler, Ph.D. in Chemical Engineering, now at Exxon
Brandon Eason, B.S. in Chemical Engineering, now in graduate school
Fenghua Deng, Ph.D. in Chemistry, now at DuPont
Angela K. Dillow, Ph.D. in Chemical Engineering, now at the University of Minnesota
Roger Glaser, Completed German Postdoctoral Fellowship, now at the University of Stuttgart.
This project provides new scientific understanding of a variety of processes in high-temperature water, and as such has the potential to contribute to a wide range of technical disciplines.
The potential advantages of reactions run in NCW include: replacing environmentally undesirable catalysts, eliminating unwanted byproducts, recycling, improved selectivity, and elimination of mass transfer limitations by changing from heterogeneous to homogeneous systems. Considering the large potential impact of environmentally benign chemical processing, only a preliminary study of chemical synthesis in high-temperature water has been done to date. Candidate processes need to be identified that can either avoid or take advantage of the thermal degradation and hydrolysis reactions that take place in near-critical water. Along with the proper scouting of potential reactions and processes for near-critical water, the elements necessary for industrial scale-up?such as the phase equilibria, reaction kinetics, reaction equilibria, and analytical process monitoring techniques?need to be determined and compiled.
Journal Articles on this Report : 4 Displayed | Download in RIS Format
|Other project views:||All 6 publications||4 publications in selected types||All 4 journal articles|
||Chandler K, Eason B, Liotta CL, Eckert CA. Phase equilibria for binary aqueous systems from a near-critical water reaction apparatus. Industrial & Engineering Chemistry Research 1998;37(8):3515-3518||
||Chandler K, Liotta CL, Eckert CA, Schiraldi D. Tuning alkylation reactions with temperature in near-critical water. Aiche Journal 1998;44(9):2080-2087||
||Chandler K, Deng F, Dillow AK, Liotta CL, Eckert CA. Alkylation reactions in near-critical water in the absence of acid catalysts. Industrial and Engineering Chemistry Research 1997;36:5175-5179.||
||Lesutis HP, Glaser R, Liotta CL, Eckert CA. Acid/base-catalyzed ester hydrolysis in near-critical water. Chemical Communications 1999;(20):2063-2064||