A Critical Evaluation of Tangential-Flow Ultrafiltration for Trace Metal Studies in Freshwater Systems. 2. Total Mercury and Methylmercury
| Autor: | Christopher L. Babiarz, David E. Armstrong, James P. Hurley, Martin M. Shafer, and Anders W. Andren, Stephen R. Hoffmann |
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| Rok vydání: | 2000 |
| Předmět: | |
| Zdroj: | Environmental Science & Technology. 34:3428-3434 |
| ISSN: | 1520-5851 0013-936X |
| DOI: | 10.1021/es991295n |
| Popis: | Laboratory and field investigations of 10 kDa polyethersulfone (PES) and regenerated cellulose (RCL) membranes were conducted to evaluate the utility of ultrafiltration (UF) for low-level mercury determinations in freshwaters. Laboratory investigations focused on blank levels, sorption loss, and charge rejection; while field investigations addressed mass balance closure, replicate precision, and permeate trends in concentration. A thorough mass balance approach was used throughout the investigation, and experiments were conducted across typical gradients in freshwater pH, specific conductance, and dissolved organic carbon (DOC). The minimum source-water HgT concentration that could be confidently processed from a 5 L volume was 0.5 ng L-1 for PES and 1.4 ng L-1 for RCL as determined by three times the standard deviation of our method blank. The minimum source-water MeHg concentration was 0.5 ng L-1 for PES and 0.2 ng L-1 for RCL based on river-water mass balance results. Mass balance closures were general... |
| Databáze: | OpenAIRE |
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