Characterization of phosphorus species in biosolids and manures using XANES spectroscopy

J Environ Qual. 2006 Oct 27;35(6):1983-93. doi: 10.2134/jeq2006.0100. Print 2006 Nov-Dec.


Identification of the chemical P species in biosolids or manures will improve our understanding of the long-term potential for P loss when these materials are land applied. The objectives of this study were to determine the P species in dairy manures, poultry litters, and biosolids using X-ray absorption near-edge structure (XANES) spectroscopy and to determine if chemical fractionation techniques can provide useful information when interpreted based on the results of more definitive P speciation studies. Our XANES fitting results indicated that the predominant forms of P in organic P sources included hydroxylapatite, PO(4) sorbed to Al hydroxides, and phytic acid in lime-stabilized biosolids and manures; hydroxylapatite, PO(4) sorbed on ferrihydrite, and phytic acid in lime- and Fe-treated biosolids; and PO(4) sorbed on ferrihydrite, hydroxylapatite, beta-tricalcium phosphate (beta-TCP), and often PO(4) sorbed to Al hydroxides in Fe-treated and digested biosolids. Strong relationships existed between the proportions of XANES PO(4) sorbed to Al hydroxides and NH(4)Cl- + NH(4)F-extractable P, XANES PO(4) sorbed to ferrihydrite + phytic acid and NaOH-extractable P, and XANES hydroxylapatite + beta-TCP and dithionite-citrate-bicarbonate (DCB)- + H(2)SO(4)-extractable P (r(2) = 0.67 [P = 0.01], 0.78 [P = 0.01], and 0.89 [P = 0.001], respectively). Our XANES fitting results can be used to make predictions about long-term solubility of P when biosolids and manures are land applied. Fractionation techniques indicate that there are differences in the forms of P in these materials but should be interpreted based on P speciation data obtained using more advanced analytical tools.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Absorption
  • Ammonium Chloride / chemistry
  • Ammonium Compounds
  • Animals
  • Bicarbonates / chemistry
  • Calcium Compounds / chemistry
  • Citrates / chemistry
  • Clinical Laboratory Techniques
  • Durapatite / chemistry
  • Ferric Compounds / chemistry
  • Fluorides / chemistry
  • Hydroxides / chemistry
  • Manure / analysis*
  • Oxides / chemistry
  • Phosphates / analysis
  • Phosphates / chemistry
  • Phosphorus / analysis*
  • Phosphorus / chemistry*
  • Phytic Acid / chemistry
  • Quaternary Ammonium Compounds / chemistry
  • Soil Pollutants / analysis*
  • Spectrometry, X-Ray Emission
  • Sulfuric Acids / chemistry
  • Water Pollutants, Chemical / analysis*


  • Ammonium Compounds
  • Bicarbonates
  • Calcium Compounds
  • Citrates
  • Ferric Compounds
  • Hydroxides
  • Manure
  • Oxides
  • Phosphates
  • Quaternary Ammonium Compounds
  • Soil Pollutants
  • Sulfuric Acids
  • Water Pollutants, Chemical
  • Ammonium Chloride
  • Phosphorus
  • ammonium fluoride
  • Phytic Acid
  • Durapatite
  • lime
  • Fluorides