Grantee Research Project Results
2001 Progress Report: Fundamental and Applied Chemistry Relevant to the Use of Humic Acids
EPA Grant Number: R828158Title: Fundamental and Applied Chemistry Relevant to the Use of Humic Acids
Investigators: Von Wandruszka, Ray
Institution: University of Idaho
EPA Project Officer: Aja, Hayley
Project Period: July 1, 2000 through June 30, 2002
Project Period Covered by this Report: July 1, 2001 through June 30, 2002
Project Amount: $188,697
RFA: Exploratory Research - Engineering, Chemistry, and Physics) (1999) RFA Text | Recipients Lists
Research Category: Water , Air , Safer Chemicals , Land and Waste Management
Objective:
The objective of the research project is to investigate the use of a bulk humic material-leonardite humic acid (LHA), commercially sold as a soil conditioner-for the detoxification of acid mine runoff polluted with heavy metals.
Progress Summary:
During this project period, we continued to study fundamental and practical aspects of LHA. In the fundamental work, we have completed a major conductance study of LHA and seven other humic materials. We have shown that the slopes of conductometric replacement titration curves can be related to the electrophoretic mobility of humic polyanions in aqueous solutions. We have proposed that this is a consequence of their molecular sizes, and have tested this hypothesis on materials of different size distributions and on size fractions generated through dialysis, medium-pressure liquid chromatography, and photolysis. Our most recent work deals with conductometric measurements of the complex formations between heavy metal ions and dissolved humic materials. So far, we have found that the associations can be monitored through the development of the solution conductance over time. This work will continue through the 1-year extension of the project.
In the applied work, we have completed a bench-scale study of zinc and trichloroethylene (TCE) extraction with an LHA-filled column. We have determined experimental parameters such as column pressurization and pH sensitivity for the process, and have quantified the extraction efficiency (95-99 percent) and extractant capacity. We have tested the process on actual mine runoff water with high zinc content and studied interference by alkaline earth metals. We found extraction to proceed without problem down to pH 4; in more acidic solutions, metal leaching was found to occur. We overcame this by including a bed of marble chips in the extraction column.
Future Activities:
During the coming year, our initial focus will be on the development of a conductometric technique for the measurement of metal complexation by dissolved humic materials. We also have recently started to look at the interactions between phosphate and dissolved humics. Phosphate loading of the waters in the Snake River Basin presently is a serious problem, and we will investigate the role of humic materials in this process.
Journal Articles on this Report : 2 Displayed | Download in RIS Format
| Other project views: | All 8 publications | 3 publications in selected types | All 3 journal articles |
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Riggle J, von Wandruszka R. Conductometric characterization of dissolved humic materials. Talanta 2002;57(3):519-526. |
R828158 (2001) R828158 (Final) |
not available |
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von Wandruszka R, Newell JD. Removal of zinc and trichloroediylene from water by column extraction with a crude humic acid. Environmental Progress 2002;21(3):209-214. |
R828158 (2001) R828158 (Final) |
not available |
Supplemental Keywords:
conductance slope, phosphate extraction., RFA, Ecosystem Protection/Environmental Exposure & Risk, Scientific Discipline, Geographic Area, Water, Waste, Remediation, Restoration, Mercury, State, Aquatic Ecosystem Restoration, Chemistry, mercury transport, Environmental Chemistry, Engineering, Chemistry, & Physics, Bioavailability, Ecology and Ecosystems, humic acids, control technologies, contaminant transport, lead, contaminated mines, Montana , acid mine discharge, acid mine drainage, restoration planning, restoration strategies, Idaho (ID), acid mine runoff, alternative cleanup standards, metal release, polychlorinated biphenyls, dynamic light scattering, analytical chemistry, aquatic ecosystems, humic acid, PCBs, mercury concentrationProgress and Final Reports:
Original AbstractThe perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.