Adsorption and Deactivation of Norflurazon by Activated Charcoal

Abstract

Laboratory and greenhouse experiments were conducted to determine if activated charcoal can remove norflurazon from water and from a sand matrix, thereby reducing its availability for plant uptake. A ratio of approximately 10:1 activated charcoal:norflurazon completely inactivated norflurazon in water. In a sand matrix, activated charcoal: norflurazon ratios of approximately 100:1 and 200 to 300:1 completely reduced norflurazon injury to cotton and to soybean and corn, respectively. The amount of activated charcoal required to remove norflurazon from soil was estimated from bioassay and regression analyses. The accuracy of this method to eliminate injury to cotton without reducing control of prickly sida and seedling johnsongrass was confirmed by bioassay using a sandy loam soil.

Formation of non-bioavailable organic residues in soil: Perspectives for site remediation

“…Part of this adsorption is due to the minerals, especially the clay fraction, and part to the organic matter (Table 2). Whereas clay minerals are responsible for adsorption of polar and hydrophilic compounds, organic matter consists of hydrophilic and Katayama et al 1995Lamoreaux et al 1989Zytner 1992Kennedy and Pham 1995 & Alexander 1995) hydrophobic regions, which results in an adsorption capability for both polar or charged and apolar or lipophilic chemicals. With respect to surface sorption in soil, it is most important since both its CEC as well as its surface area are higher than any other soil component (Table 2).…”

Effect of Mycorrhizal Inoculation and Activated Charcoal on Growth and Nutrition in Peach (<i>Prunus persica</i> Batsch) Seedlings Treated with Peach Root-Bark Extracts

“…1). Charcoal is useful as a soil amendment because of its ability to adsorb phytotoxic substances (Lamoreaux et al, 1989). However, in this study, activated charcoal is likely to have delayed the establishment of mycorrhizal symbiosis by adsorbing exudates that leak from respiring roots and play a critical role in the host/fungus signaling events that precede the establishment of symbiosis.…”

“…In particular, the ability of activated charcoal to remove residual herbicides from the soil solution has been widely investigated. Lamoreaux et al (1989) reported the complete recovery of norflurazon, a fluorinated pyridizanone herbicide from water, soil, and sand matrixes by activated charcoal when applied at varying concentrations. Ishii and Kadoya (1994) also reported that media amendment with charcoal has a positive effect on mycorrhizal symbiosis.…”

Reclamation techniques for soils treated with non-selective residual herbicides (soil sterilants) /

“…They found that these levels were not adequate to prevent herbicide damage on a clay loam soil. Lamoreaux et al (1989) used rates of charcoal to norflurazon of approximately 100:1, 200:1, and 300:1 to reduce herbicide injury to cotton, soybean and corn, respectively from a sand matrix. In a greenhouse study with silty clay (tropical) soil charcoal to herbicides ratios as low as 66:1 (propazine) were found to be effective in preventing herbicide injury in beans, but ratios of 3600: 1 were required to prevent picloram injury.…”