Extratores de silîcio disponível em escórias e fertilizantes

摘要: Methods to quantify available silicon (Si) in fertilizers and slags are not yet sufficiently trustworthy. In this study, Si extracted from several sources was analyzed, using the extractors: Na2CO3 + NH4NO3 varying concentration, time of agitation reaction; water; HCl 0,5 mol dm-3; 50 g dm-3 Na2CO3; citric acid; 0,5 mol dm-3 acetic acid cation exchange resin (Amberlite IRC-50, pK 6.1); leaching column method. A greenhouse experiment, where 125 kg ha-1 total 12 different applied on irrigated rice, also conducted. For determination Si, shaking duration essential, although 3 h entailed a statistically superior result. The concentrations 10 16 g dm-3 30 48 g dm-3 proved be most promising for extraction. smaller concentration (10 16 g dm-3) therefore chosen evaluate relation settling time. All increased solubility during rest period. best correlation between uptake by rice plants detected various analyzed found period day 5 9. According results, extractor evaluates adequately can used as method determine potential release soil its availability plants. efficient source solubilization Rhodia, followed Wollastonita, while MB-4 blast furnace slag provided less Si. extractors were more at extracting with Wollastonita. Water that presented lowest recovery rate. contents crop achieved Amberlite 10 g dm-3 16 g dm-3, column-method.