Patent · US Expired

Fluorescence analyzer for lignin

US5220172A · kind A · utility

27Cited by
4References
19Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 23, 1991
Grant dateJun 15, 1993
Priority date
Expiry dateSep 23, 2011

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01N2201/084
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A method and appartus for measuring lignin concentration in an undiluted sample of wood pulp or black liquor comprises a light emitting arrangement for emitting an excitation light through optical fiber bundles into a probe which has a sensing end facing the sample. The excitation light causes the lignin concentration to produce fluorescent emission light which is then conveyed through the probe to analyzing equipment which measures the intensity of the emission light. Measures are taken to maximize the emission light intensity which is due to lignin concentration and distinguish it from background and interfering light. The fluorescent light intensity is found to drop off in a predictable manner with increased lignin concentration.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.