Abstract: Liquid petroleum products are marked with markers having the formula: ##STR1## wherein the R.sub.1 's and the R.sub.2 's are the same or different and are each selected from --H and C.sub.1 -C.sub.7 alkyls; provided that at least one, and preferably both, R.sub.1 's are a C.sub.3 -C.sub.7 alkyl; and provided that the R.sub.3 's are the same or different and are selected from --H, --NO.sub.2, --Br, --F, --CN, and --Me; and provided that at least one R.sub.3 is selected from --NO.sub.2, --Cl, --Br, --F, and --CN.

Abstract: Tagging compounds (which function as both dyes and markers) having the following structures: ##STR1## wherein x is an integer between 0 and 3 inclusive, y is an integer between 1 and 3 inclusive, z is 0 or 1, and R is a straight or branched chain hydrocarbon having from 1 to 5 carbon atoms are disclosed. These compounds can be dissolved in a diluent at a concentration of from about 10 percent to about 30 percent, forming a concentrate which can be further dispersed in an organic liquid to form a final concentration of from about 1 ppm to about 15 ppm of said tagging compound in said liquid. Methods for detecting the presence of a tagged compound in an organic liquid are also disclosed.

Abstract: Tagging compounds (which function as both dyes and markers) having the following structures: ##STR1## wherein x is an integer between 0 and 3 inclusive, y is an integer between 1 and 3 inclusive, z is 0 or 1, and R is a straight or branched chain hydrocarbon are disclosed. These compounds can be dissolved in a diluent at a concentration of from about 10 percent to about 30 percent, forming a concentrate which can be further dispersed in an organic liquid to form a final concentration of from about 1 ppm to about 15 ppm of said tagging compound in said liquid. Methods for detecting the presence of a tagged compound in an organic liquid are also disclosed.

Abstract: A two-component liquid reagent and process is provided for detecting the presence of furfural in petroleum products.

Abstract: New markers for petroleum fuels; a method of marking said fuels with a marker and of subsequently detecting the presence of said marker; and marked fuels are provided. The markers include the following compounds: ##STR1## 1-(4-morpholino)-3-(alpha naphthylamino)-propane, ##STR2## 1-(4-morpholino)-3-(beta naphthylamino)-propane, ##STR3## where R.sub.1 and R.sub.2 may be hydrogen or alkyl having from one to twenty carbon atoms.The marker is detected in said marked fuel by (1) extraction with an acidic aqueous solution and (2) admixture with a stabilized solution of diazotized 2-chlor-4-nitroaniline to yield a color characteristic of the marker.

Abstract: Novel disazo colorants or dyes for marking organic liquids, the colorants having the general formula ##STR1## where R.sub.1 is H, CF.sub.3, or alkyl having from 1 to 4 carbon atoms,R.sub.2 is H, or alkyl having from 1 to 4 carbon atoms,R.sub.3 and R.sub.4 are each H, OCH.sub.3, OC.sub.2 H.sub.5 or CH.sub.3, andR.sub.5, r.sub.6 and R.sub.7 are each H, or alkyl having from 1 to 12 carbon atoms, at least one of said R.sub.5, R.sub.6 and R.sub.7 being alkyl.The novel compound of the general formula ##STR2## where R.sub.5, R.sub.6 and R.sub.7 are as described above is provided and is useful as an intermediate in the preparation of said disazo colorants. Methods for the preparation of the colorants are disclosed together with qualitative and quantitative procedures for detecting these colorants in the marked liquids.

Abstract: Novel disazo colorants or dyes for marking organic liquids, the colorants having the general formula ##STR1## where R.sub.1 is H, CF.sub.3, or alkyl having from 1 to 4 carbon atoms,R.sub.2 is H, or alkyl having from 1 to 4 carbon atoms,R.sub.3 and R.sub.4 are each H, OCH.sub.3, OC.sub.2 H.sub.5 or CH.sub.3, andR.sub.5, r.sub.6 and R.sub.7 are each H, or alkyl having from 1 to 12 carbon atoms, at least one of said R.sub.5, R.sub.6 and R.sub.7 being alkyl.The novel compound of the general formula ##STR2## where R.sub.5, R.sub.6 and R.sub.7 are as described above is provided and is useful as an intermediate in the preparation of said disazo colorants. Methods for the preparation of the colorants are disclosed together with qualitative and quantitative procedures for detecting these colorants in the marked liquids.

Abstract: Azo dyes which are highly soluble in petroleum fuels. The dyes have the general formula ##STR1## where R.sub.1, R.sub. 2, R.sub. 3, and R.sub.4 are each H or CH.sub. 3 and R.sub. 5 is either 2-ethylhexyl or 2-ethylhexyloxypropyl. When R.sub. 5 is 2-ethylhexyl, then at least one of R.sub.1, R.sub.2, R.sub.3 and R.sub.4 is CH.sub.3. When R.sub.5 is 2-ethylhexyloxypropyl, then each of R.sub.1, R.sub.2, R.sub.3 and R.sub.4 is H, or at least one of R.sub.1, R.sub.2, R.sub.3 and R.sub.4 is CH.sub.3 provided that R.sub.1 and R.sub.3 are not both CH.sub.3 at the same time that R.sub.2 and R.sub.4 are each H, and provided that R.sub.2 and R.sub.4 are not both CH.sub.3 at the same time that R.sub.1 and R.sub.3 are both H.