Characterization of phosphate species in urban sewage sludges by high‐resolution solid‐state ³¹P NMR

Abstract

The mineral forms of phosphorus in three urban sewage sludges were characterized using highresolution solid-state phosphorus-3 1 nuclear magnetic resonance (NMR) coupled to a sequential extraction. The sludges studied were an anaerobically-digested and heat-treated sludge (ParisAchbres), an activated sludge (Briare) and an anaerobically-digested sludge (Nancy). NMR observations were conducted using both single-pulse and cross-polarization sequences in order to distinguish between 'lP nuclei far from 'H nuclei, and 31P located within a fraction of a nanometre of 'H. This approach showed that a complex mixture of P species was present in these sludges. A mixture of hydrogenated octocalcium phosphates and apatites was observed in the three samples. Monetite was present in the anaerobically-digested sludge and brushite in the activated sludge. Dehydrogenated condensed calcium phosphates (compounds with a Ca : P ratio higher than 1 .O such as fluorapatite or tricalcium phosphate) and dehydrogenated pyrophosphates were also probably present in the anaerobically-digested sludge. A poorly-ordered wavellite was observed in the three sludges after the HC1 extraction. However, results were inconclusive as to whether this mineral was present in the three sludges, or had been precipitated during the sequential extraction.

Effects of phosphorus-based application of animal manure compost on the yield of silage corn and on soil phosphorus accumulation in an upland Andosol in Japan

“…We used the modified method of Hedley et al (1982) to characterize the P fractionation in the manure composts. In the fractionation method (Frossard et al 1994), we sequentially extracted the manure composts with H 2 O (1:200 weight/volume), 0.5 mol L −1 NaHCO 3 (pH = 8.5), 0.1 mol L −1 NaOH and 1 mol L −1 HCl. After each extraction, which was conducted with continuous shaking for 16 h at 25°C, the P concentration of the supernatant was measured colorimetrically (Murphy and Riley 1962).…”

“…The P solubility or availability in manure or manure compost is the key for defining P-based compost management, but this property varies among manure types and composting methods (Ito et al 2010). The fractionation method of Frossard et al (1994) has been widely used for evaluating P characteristics in manure compost. Frossard et al (1994) modified the soil P fractionation method developed by Hedley et al (1982) for the evaluation of P in organic matter.…”

“…The fractionation method of Frossard et al (1994) has been widely used for evaluating P characteristics in manure compost. Frossard et al (1994) modified the soil P fractionation method developed by Hedley et al (1982) for the evaluation of P in organic matter. The procedure involves sequential extraction by water (H 2 O), sodium bicarbonate (NaHCO 3 ), sodium hydroxide (NaOH) and hydrochloric acid (HCl).…”

Soil Organic Phosphorus Speciation Using Spectroscopic Techniques

“…Variations in the intensity of SSBs have been noted by Frossard et al (1994), Williams et al (1981) and Hinedi and Chang (1989), but they were not used to identify specific P pools or compounds in soils. Dougherty et al (2005) used a combination of CP and DP with selective extractions, and reported that organic P could be identified by its broad resonance and prominent SSBs, in comparison with the considerably sharper resonances and smaller SSBs of inorganic P. It has been proposed that SSBs can also be used to distinguish between phytate and inorganic orthophosphate species when the major resonances of both compounds are similar (He et al 2007c).…”

“…Rarely have solid-state 31 P NMR studies focused on determining organic P concentrations or identifying individual P compounds in whole soils (Newman and Condron 1995;Condron et al 1997;McBeath et al 2006;Conte et al 2008). Instead, much research has dealt with the application of solidstate NMR in differentiating between inorganic metal-P species and determining the relative amount of whole-soil inorganic and organic P (Hinedi and Chang 1989;Frossard et al 1994Frossard et al , 2002McDowell et al 2002a, b).…”