Characterization of Phosphorus in Sludge Extracts Using Phosphorus-31 Nuclear Magnetic Resonance Spectroscopy
1989
Hinedi, Zeina R. | Chang, A. C. | Lee, R. W. K.
Nuclear magnetic resonance spectroscopy (³¹P NMR) was used to characterize the phosphorus (P) extracted from selected municipal sewage sludges. Aqueous and nonaqueous extraction schemes were studied. The trichloroacetic acid/KOH two-step extraction and the 0.5 M NaOH extraction were effective in recovering P from sludges. It was found that the P distribution pattern is sludges was affected by the sludge digestion processes. Almost all of the P in anaerobically digested sludges was inorganic. In the waste-activated sludge and aerobically digested sludges, more than 50% of the total P was present as P-monoesters and P-diesters. Several experiments were conducted to confirm P-diester peak assignment. Incubation of the sludge with ribonuclease caused a decrease of the peak in the P-diester region, indicating that at least a part of the P-diesters is in the form of RNA. Results of a dialysis experiment appeared to indicate that P-diesters were broken down from the molecular weight >1000 material to their lower molecular weight components during sludge digestion. The peaks appearing in the ³¹P NMR spectra of sludge-borne phospholipids were tentatively assigned to phosphatidylcholine, phosphatidylserine, phosphatidylethanolamine, and phosphatidylglycerol or diphosphatidylglycerol. Contribution from the Dep. of Soil and Environ. Sci. and the Dep. of Chemistry, Univ. of California, Riverside.
Show more [+] Less [-]AGROVOC Keywords
Bibliographic information
This bibliographic record has been provided by National Agricultural Library