title: Determination of phosphorus in lubricating oils by cool-flame emission spectroscopy.
abstract: The phosphorus content of lubricating oils is determined by measurement of the emission from the HPO molecular species at 528 nm in a cool hydrogen-nitrogen diffusion flame. The oil is ashed in the presence of potassium hydroxide and an aqueous extract of the melt is treated with ion-exchange resin to remove interferents, before aspiration into the flame. Analytical results are presented on samples containing phosphorus in the range 0.009-0.2%. The precision of the method is +/- 5% at the 0.04% phosphorus level.
authors.affiliation: Quality Assurance Directorate (Materials) Royal Arsenal London, S.E.18U.S.A.
authors.forename: W N
authors.initials: WN
authors.lastname: Elliott
authors.forename: C
authors.initials: C
authors.lastname: Heathcote
authors.forename: R A
authors.initials: RA
authors.lastname: Mostyn