COLL 275 |
| Nano boron is a promising solid fuel and propellant being considered for use by the US Army. Hence, the impact of its release on the environment was investigated in aggregation and deposition experiments. It was also characterized for particle size and surface charge under various aquatic chemistries. Two regimes of reaction-controlled and diffusion-controlled were observed in the aggregation tests, yielding critical coagulation concentrations (CCC) of 200, 1.5 and 0.7 mM for NaCl, MaCl2, and CaCl2, respectively. The values of the observed CCC under different electrolytes regimes corresponded to the theoretical ones expected by the Schulze-Hardy rule. In column deposition tests, deposition attachment rates increased with increasing electrolyte concentrations until they reached constant values at critical concentrations. This phenomenon is similar to the effect of electrolyte on the aggregation process. Both aggregation and deposition results could be explained by the classical Derjaguin-Landau-Verwey-Overbeek (DLVO) theory. |
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The Physical Chemistry of Environmental Interfaces
6:00 PM-8:00 PM, Monday, April 7, 2008 Morial Convention Center -- Rm. 244/245, Poster
Division of Colloid & Surface Chemistry |