This study investigated the possibility of mineral (biotite, bentonite, fuller's earth)
amendment to Fe(0)-based treatment system in the groundwater for enhancing nitrate
reduction. It was expected that amendment of mineral surfaces enhances nitrate
reduction by providing surfaces to form green rusts or reaction precipitates to prevent
passivation of Fe(0) surfaces, as well as to adsorb produced ammonium. Batch tests for kinetics experiments were conducted by adding 20 mL solutions to 25 mL
plastic vials containing 0.5 g of Fe(0) and 0.5 g of minerals. Other experiments were
carried out by changing the amount of bentonite, fuller's earth, and biotite (0.01-0.5 g) in
vials containing 0.5 g of Fe(0) with GW solutions. The reduction experiments were
performed at room temperature (25±0.2ºC) for 64 h. The adsorption experiments were
performed with bentonite and fuller's earth by batch method for 24 h. All the samples
were shaken by a shaking incubator (shaking water bath, BS-31) with 150 rpm, filtered
through 0.45 µm PVDF filter (Whatman) and diluted for NO<sub>3</sub><sup>-</sup>, NH<sub>4</sub>
<sup>+</sup> analysis.
Nitrate, sulfate, and chloride concentrations were measured by ion chromatography (Dionex
CX-120). Ammonium was measured using Nessler method with UV/VIS
spectrophotometer (DR4000/HACH). The solution pH in batch experiments was
measured using a pH meter (Horiba, Ltd. Kyoto, Japan). The concentrations of cations in groundwater were measured by inductively coupled plasma-optical emission
spectrometer (ICP-OES, Ultima 2C, Horiba). Includes 34 references, tables, figures.
| Edition : | Vol. - No. |
| File Size : | 1
file
, 1.1 MB |
| Note : | This product is unavailable in Ukraine, Russia, Belarus |
| Number of Pages : | 10 |
| Published : | 11/01/2009 |
