Apparatus and method for analyzing the hydrocarbon type composition of gasoline

A method for analyzing a gasoline sample comprising saturates, olefins and aromatics, which method comprises:

• (a) passing said sample through an absorption column whereby said aromatics are retarded while the effluent passes through;
• (b) passing said effluent from step (a) through a copper on silica gel column wherein said olefins are adsorbed and temporarily retained;
• (c) detecting the amount of said saturates present in said sample;
• (d) backflushing said aromatics from said absorption column;
• (e) detecting the amount of said aromatics present in said sample;
• (f) heating said copper on silica gel column to release said olefins;
• and
• (g) detecting the amount of olefins present in said sample.

A method for analyzing the saturates, olefins and aromatics content in a gasoline sample by utilizing a carrier gas to move said sample through valves and columns to a detector, which comprises:

• (a) passing said sample through an absorption column whereby said aromatics are retarded while said saturates and olefins pass through;
• (b) passing said saturates and olefins from step (a) through a copper on silica gel column wherein said olefins are temporarily retained while said saturates pass through;
• (c) detecting the amount of saturates present in said sample;
• (d) backflushing with carrier gas said aromatics from said absorption column directly to said detector;
• (e) detecting the amount of aromatics present in said sample;
• (f) heating said copper on silica gel column from about 200.degree. C. to about 375.degree. C. whereby said olefins are released from said column;
• and
• (g) detecting the amount of olefins present in said sample.

An apparatus for analyzing the compositions of various gasoline samples, which comprises:

• (a) a sample injector;
• (b) an absorption column for retarding aromatics contained in said sample;
• (c) a copper on silica gel adsorption column for separating olefins from saturates contained in said sample;
• (d) a valve means for reversing the flow of said sample through said absorption column for retarding aromatics;
• (e) a valve means for directing the flow of said sample around said copper on silica gel adsorption column;
• (f) a means for detecting the amount of aromatics, olefins and saturates contained in said sample;
• (g) conduits adjoining said aforementioned columns, valves and detecting means;
• (h) temperature control means for controlling the temperature of said copper on silica gel adsorption column;
• and
• (i) a means for controlling said valve means to control the direction of flow of said sample to said detector.

An apparatus for analyzing the compositions of various gasoline samples, which comprises:

• (a) a heated enclosure housing an absorption column for retarding the flow of aromatics, a multidirectional backflush valve and a multi-directional bypass valve;
• (b) a sample injector positioned upstream of said heated enclosure;
• (c) a temperature controllable aluminum block containing a copper on silica gel column for temporarily retaining olefins, said block situated downstream of said heated enclosure;
• (d) a detector positioned downstream from said columns;
• (e) conduits connecting said backflush valve to said sample injector and to both ends of said absorption column, and to said bypass valve;
• (f) conduits directly connecting said bypass valve to said copper on silica gel column and to said detector;
• (g) a conduit connecting said copper on silica gel column to said detector;
• (h) a carrier gas inlet line attached to said bypass valve;
• (i) means for injecting a sample along with a carrier gas into said injector;
• (j) means for regulating said valves to alter the direction of said sample through said columns;
• (k) means for controlling the temperature of said copper on silica gel column.