Method and apparatus for chromatographically analyzing a liquid sample

A chromatographic analysis method for the selective detection in a sample of organic nitrogen containing compounds, the method comprising the steps of:

• in a liquid chromatograph, chromatographically separating organic nitrogen containing compounds from other compounds in a liquid sample and discharging such separated compounds from the chromatograph in timewise distribution;
• injecting into a converter at least a portion of the sample having therein organic nitrogen containing compounds discharged from the chromatograph;
• introducing into the converter oxygen in an amount sufficient to fully oxidize combined nitrogen in organic compounds within that portion of the sample injected into the converter;
• in the converter, oxidizing the organic nitrogen containing compounds discharged from the chromatograph at a temperature effective to oxidize combined nitrogen therein and ineffective to oxidize free nitrogen in a substantial amount;
• transferring effluent from the converter to an oxides of nitrogen detector;
• and
• measuring in the detector the oxides of nitrogen transferred from the converter.

chromatograph system for detecting in a liquid sample organic nitrogen containing compounds comprising:

• a liquid chromatograph for separating constituents of the sample and discharging the separated constituents in timewise distribution;
• a converter for oxidizing effluent from said chromatograph to convert the nitrogen in organic nitrogen containing compounds to nitric oxide;
• means in said converter forming an inlet for oxygen;
• means for maintaining the temperature of said converter at a predetermined level approximately in the range 600.degree. C to 1800.degree. C;
• means for atomizing effluent from said chromatograph into said converter;
• and
• means for detecting nitric oxide in discharge from said converter.

A chromatograph system for detecting in a liquid sample organic nitrogen containing compounds comprising:

• a liquid chromatograph for separating constituents of the sample and discharging the separated constituents in timewise distribution;
• a converter for oxidizing effluent from said chromatograph to convert the nitrogen in organic nitrogen containing compounds to oxides of nitrogen;
• means in said converter forming an inlet for oxygen;
• means for maintaining the temperature of said converter at a predetermined level in the range effective to convert combined nitrogen in organic nitrogen containing compounds to oxides of nitrogen and ineffective to oxidize free nitrogen in substantial amounts;
• means for atomizing effluent from said chromatograph into said converter;
• and
• means for detecting oxides of nitrogen in discharge from said converter.

A chromatographic analysis method for the selective detection in a sample of organic sulphur containing compounds, the method comprising the steps of:

• in a liquid chromatograph, chromatographically separating organic sulphur containing compounds from other compounds in a liquid sample and discharging such separated compounds from the chromatograph in timewise distribution;
• injecting into a converter at least a portion of the sample having therein organic sulphur containing compounds discharged from the chromatograph;
• introducing into the converter oxygen in an amount sufficient to fully oxidize combined sulphur in organic compounds within that portion of the sample injected into the converter;
• in the converter, oxidizing the organic sulphur containing compounds discharged from the chromatograph at a temperature effective to oxidize combined sulphur therein and ineffective to ozidize free sulphur in a substantial amount;
• transferring effluent from the converter to an oxides of sulphur detector;
• and
• measuring in the detector the oxides of sulphur transferred from the converter.

A chromatographic system for detecting in a liquid sample organic sulphur containing compounds comprising:

• a liquid chromatograph for separating constituents of the sample and discharging the separated constituents in timewise distribution;
• a converter for oxidizing effluent from said chromatograph to convert the sulphur in organic sulphur containing compounds to oxides of sulphur;
• means in said converter forming an inlet for oxygen;
• means for maintaining the temperature of said converter at a predetermined level in the range effective to convert combined sulphur in organic sulphur containing compounds to oxides of sulphur an ineffective to oxidize free sulphur in substantial amounts;
• means for atomizing effluent from said chromatograph into said converter;
• and
• means for detecting oxides of sulphur in discharge from said converter.