Solvent compositions for removing petroleum residue from a substrate and methods of use thereof

A method of cleaning highway and road construction equipment comprising:

• placing equipment on a perforated grid;
• spraying a biodegradable solvent composition with a spray gun under pressure on a residue;
• containing equipment thereby forming an aqueous sludge, wherein the solvent composition has a pH of about 7;
• filtering the aqueous sludge through the perforated grid and thus separating insoluble contaminates;
• subjecting the filtered aqueous sludge to a compressed gas and thereby separating the solvent composition from the residue;
• and
• preparing the solvent composition for recycling or disposal,
• wherein the solvent composition comprises:
• 10-60 weight % of an alkylated benzoic acid ester selected from the group consisting of:
• methyl benzoic acid ester, ethyl benzoic acid ester, n-propyl benzoic acid ester, isobutyl benzoic acid ester, n-butyl benzoic acid ester, tent-butyl benzoic acid ester, isomers of pentyl benzoic acid ester, isopropyl benzoic acid ester, and combinations thereof;
• about 40-70 weight % of a biodiesel;
• about 0-15 weight % of diethylene glycol monobutyl ether or an aqueous solution thereof;
• about 0-10 weight % d-limonene;
• about 0-1 weight % of an odor-masking agent;
• about 0-20 weight % ethoxylated Castor oil;
• and
• a corrosion inhibitor.

A method of cleaning highway and road construction equipment comprising:

• placing equipment on a perforated grid;
• spraying a biodegradable solvent composition with a spray gun under pressure on a residue containing equipment thereby forming an aqueous sludge, wherein the solvent composition has a pH of about 7;
• filtering the aqueous sludge through the perforated grid and thus separating insoluble contaminates;
• subjecting the filtered aqueous sludge to a compressed gas and thereby separating the solvent composition from the residue;
• and
• preparing the solvent composition for recycling or disposal,
• wherein the solvent composition comprises:
• 10-60 weight % of an isopropyl benzoic acid ester;
• about 30-60 weight % of a biodiesel;
• about 0-15 weight % of a diethylene glycol ether or an aqueous solution thereof;
• about 0-10 weight % of a cyclic terpene or terpenoid;
• about 0-1 weight % of an odor-masking agent;
• about 0-20 weight % of a nonionic surfactant;
• and
• a corrosion inhibitor,
• wherein the composition is at least as efficient as diesel fuel for removing petroleum residue from a substrate, has a flash point of at least 60° C., and comprises no trace amounts of Volatile Organic Compounds (VOCs) above the limits disclosed in Method 8260B of the Environmental Protection Agency (EPA).