A fuel stabilizer formulation includes a hybrid component that acts as an antioxidant, a chelating agent, and lubricant when added to the fuel, one or more vapor suppressants, and a water scavenger. Furthermore, the formulation may include components that bond with gasoline compounds to prevent evaporation of low-end components, form a layer along with the engine metal that prevents condensed water from corroding the metal, prevent corroded metal ions from destabilizing gasoline compounds into resin, and scavenge water to prevent water deposits at the bottom of the tank which limits biological activity, resulting in an overall improvement in oxidation stability over conventional fuel stabilizers.

High temperature antioxidant additives and methods for improving a liquid fuel composition's thermal oxidative stability are disclosed. Also provided are liquid fuel compositions including a liquid fuel and the high temperature antioxidant additives. The high temperature antioxidant additive may include an alkylpiperidin-1-yl alkylcarbamate.

A fuel oil composition comprising a blended fuel oil having a sulfur content of less than 5000 ppm and an additive wherein the additive is a copolymer comprising maleic anhydride derived units and α-olefin derived units.

The use of tetrahydrobenzoxazines I ##STR00001##
where R.sup.1 is a hydrocarbyl radical and R.sup.2, R.sup.3, R.sup.4 and R.sup.5 are each independently hydrogen atoms, hydroxyl groups or hydrocarbyl radicals, and where R.sup.2 to R.sup.5 may also form a second and a third tetrahydrooxazine ring, with the proviso that at least one of the substituents has from 4 to 3000 carbon atoms and the remaining substituents, when they are hydrocarbyl radicals, each have from 1 to 20 carbon atoms, as stabilizers for stabilizing inanimate organic material, especially turbine fuels, against the action of light, oxygen and heat.

A composition for inhibiting oxidation including an anionic, hydrophilic, water soluble polymer, wherein the polymer is chosen from the group consisting of anionic polyacrylamide, methylcellulose, xanthan gum, guar gum, and lignin sulfonate, an anionic surfactant, a co-solvent, and water is herein disclosed.

A compound represented by the formula:

##STR00001## wherein each R is independently selected from the group consisting of (i) substituted or unsubstituted alkyl with C=0 to 12 inclusive; wherein X.sup.1, X.sup.2, X.sup.3 and X.sup.4 are each independently selected from the group consisting of alkyl, aryl, alkylaryl groups and hydrogen; wherein R.sup.1, R.sup.2, R.sup.3, and R.sup.4 are each independently selected from the group consisting of alkyl, aryl, alkylaryl groups and hydrogen; and wherein one of R.sup.1 and R.sup.2 and one of R.sup.3 and R.sup.4 may optionally be bridged by a polymethylene group to form a cycloalkyl; wherein when C=0 in R, the combined group R.sup.1 R.sup.2 is the same as the combined group R.sup.3 R.sup.4; and wherein when C=1 in R, each of R.sup.1, R.sup.2, R.sup.3, and R.sup.4 are hydrogen.

A method of making antidegradant compounds is disclosed, in which a p-phenylenediamine is reacted with an alpha-hydroxy carbonyl compound to thereby obtain an enediamine, which is reduced to thereby obtain a mixture comprising the antidegradant compound.

Methods of making antidegradant compounds are disclosed in which a p-phenylenediamine is reacted with a dicarbonyl to thereby obtain a diimine, which is reduced to obtain mixtures comprising the antidegradant compound.

Antidegradant compounds are disclosed, and methods of making them, that are represented by the formula I:

##STR00001## wherein each X is independently selected from the group consisting of ethyl, methyl, or hydrogen.

Also disclosed are diimine intermediates corresponding to formula III:

##STR00002## wherein each X is independently selected from the group consisting of ethyl, methyl, or hydrogen. These intermediates themselves exhibit antidegradant activity.

A biodiesel composition comprising a stabilization agent is disclosed. The stabilization agent comprises depolymerized lignin having a weight average molecular weight of at least 360 g/mol and at most 5000 g/mol, and the TEAC value of the depolymerized lignin is at most 50% of the TEAC value of a corresponding lignin before having been depolymerized, and wherein the weight average molecular weight of the depolymerized lignin is at most 60% of the weight average molecular weight of the corresponding lignin.