MXPA01000045A - Heavy oil remover - Google Patents

Abstract

A heavy oil remover comprises from about 0.1 to about 99 weight percent dipropylene glycol Mono N-butyl ether, from about 1 to about 99 percent of a mixture of methyl cocoate and methyl sunflowerate, from about0.1 to about 75 weight percent naphthenic petroleum distillate solvent, from about 0.1 to about 90 weight percent salt of an alkyl aromatic sulfonic acid, from about 0.05 to about 50 weight percent branched alcohol ethoxylate, from about 0.05 to about 50 weight percent ethoxylated alkyl mercaptan, and the balance, water.

Description

HEAVY OIL REMOVER FIELD OF THE INVENTION This invention deals in general terms with the formula for a heavy oil remover. In particular, the invention deals with a composition useful for removing oil and fatty deposits from process equipment such as storage tanks, transfer pipes and pumping installations.

BACKGROUND OF THE INVENTION Compositions are known for removing heavy oils from fat deposits that remain in process equipment, for example oil storage tanks. The heavy oil degreasing compositions contain what are known as "alkaline builders". In addition, many heavy oil remover compositions contain halogens that are not recommended for the degreasing of steel process equipment, because halogens can contribute to accentuate metal cracking. Many heavy oil degreasers only work when they keep their degree of total concentration and are not effective when diluted in liquid waste that contains the process equipment to be cleaned. Some heavy oil degreasers are not effective at ambient temperatures and must be heated together with the process equipment in order to remove sediment from heavy oil. Traditional heavy oil removers are not able to absorb or neutralize the toxic gases and vapors that have accumulated inside the dirty process equipment. Finally, many of the compositions of the first heavy oil removers are toxic and non-biodegradable. U.S. Patent 5085710 to Goss discloses a composition for removing oil sludge using an alkylphenol adduct and a castor oil ethoxylate. US Patent 5389156 to Mehta et al. Discloses a heavy oil degreaser containing a terpene and a second nonionic surfactant coagent from the family of ethylene oxide-propylene oxide polyol adducts. Both formulations have many characteristics that are not advisable, which are mentioned later. It would be convenient to develop a heavy oil remover composition that is free of alkaline and halogen improvers, as well as being effective both at significant levels of dilution and at ambient temperatures; able to absorb toxic gases and vapors such as hydrogen sulfide and benzene; non-toxic and biodegradable.

SUMMARY OF THE INVENTION According to the present invention, an amazing heavy oil remover has been discovered, containing: Approximately from 0.1 to 0.9 average weight of dipropylene glycol mono N-butyl ether; Approximately from 1 to 99 percent of a mixture of methyl cocoate and methyl tursolate; Approximately from 0.1 to 75 average weight of naphthenic petroleum distillate solvent; Approximately from 0.1 to 90 weight average salt of an alkylaromatic sulphonic acid; Approximately 0.05 to 50 average weight of branched alcohol ethoxylate; Approximately 0.05 to 50 average weight of ethoxylated alkyl thiol; and the balance, water. The utility of the heavy oil remover according to the present invention lies especially in the removal of grease deposits from dirty process equipment such as oil storage tanks.

DETAILED DESCRIPTION OF THE PREFERRED CONTRIBUTIONS The composition of the heavy oil remover according to the present invention contains dipropylene glycol mono N-butyl ether, a mixture of methyl cocoate and methyl girasolate, a solvent distilled from naphthenic petroleum, a salt of an alkylaromatic sulfonic acid, an ethoxylate branched alcohol, an ethoxylated alkyl thiol and water. The design of a high quality heavy oil remover requires attention to the physical characteristics related to the processing requirements necessary for the removal of heavy oils at ambient temperatures. Especially, the most important chemical characteristics are the capacity of dissolution and detergent (or emulsion capacity). These factors affect the ability of the heavy oil remover to clean and degrease metal surfaces, their corrosive impact on them, their safe handling and their capacity for environmental acceptance. The heavy oil remover in accordance with the present invention shows the desired dissolution and detergent characteristics. In addition, its formulation does not contain halogens, which reduces the chances of accentuating the cracking of the steel process equipment. The novel formulation is effective at ambient temperatures, even when diluted to a considerable degree of water or fluids remaining from the process. Finally, the composition can absorb toxic vapors such as hydrogen sulfide and benzene, even the same composition is biodegradable and non-toxic. The naphthenic petroleum distillate solvent according to the present invention shows a synergistic dissolving effect with the dipropylene glycol dimethyl ether and the mixture of methylcoconate and methyl-tursolate. Distilled naphthenic petroleum solvents are well known in this area as useful solvents derived from the oil refinery sector. The petroleum naphthenic distillate solvent can be found in the formulation of the present heavy oil remover at concentrations of about 0.1 to 75 average weight. Preferably, the concentration is about 5 average weight. The naphthenic petroleum distillate solvent, which is particularly preferred, is available from Exxon Chemical Company under the name "EXXSOL D-60". The mixture of methyl coconate and methyl girasolate according to the present invention contains a mixture of methyl ester solvents derived from the fatty acids of coconut oil and sunflower oil. It is possible that the ratio of methyl cocono to methyl tursolate varies above the maximum limits from about 1 to 99 to almost 99 to 1. Preferably the ratio is from about 40 to 60 to about 60 to 40. The concentration of the mixture of methylcoconate and methylrolysolate as a percentage of the heavy oil remover if the average weight ranges from about 1 to 99. Preferably, the concentration is about 10 average weight. The most preferred mixture of methylcoconate and methylolsolate is available from Alzo, Inc., a New Jersey company, with the name "DEGREEZ". The dipropylene glycol mono N-butyl ether is included in this formulation and acts as a surfactant coagent. In addition, this is a well-known compound and is present in this novel formulation at a concentration of approximately 0.1 to 99 average weight. Preferably, the concentration is around 5 average weight. The most preferred dipropylene glycol mono N-butyl ether is available from Dow Chemical Company under the name "DOWANOL DPNB". In the novel formulation is an amine, alkali metals or ammonium salt of an alkylaromatic sulphonic acid in the form of an anionic emulsifier. The alkylaromatic hydrophobe blends perfectly into the petroleum sediments. The linkage of the alkylaromatic sulfonate with the alkyl radical is weaker than a bond between an alkylaromatic sulphonate radical and an alkali metal atom such as sodium. This is important to control the degree to which the final product will be available to emulsify the petroleum sediment, since a weak emulsion that easily breaks down with the presence of minerals in the wastewater and flows into the process equipment that is It is cleaning, it is recommended in order to recover quickly the oil that will eventually be separated. In addition, the use of the alkylamine salt in a preferred delivery eliminates the need for an ammonium salt which is used in many traditional degreasers. On the other hand, this preferred surfactant emulsifier produces little foam, compared to traditional anionic surfactants. Conveniently, this preferred ingredient, due to its functional group of weakly bound amines, acts as an aggressive and partial neutralizing absorbent for acid gases such as hydrogen sulfide. It is possible that the necessary ingredient is an amine, alkali metals or the ammonium salt of a sulfonic acid alkyl benzene or alkyl thiol. Examples to be followed include, but are not limited to, an isopropylamine salt of linear sulfonic acid dodecylbenzene, a salt of branched sulphonic acid dodecylbenzene isopropylamine, as well as mixtures of these. A preferred salt of an alkylaromatic sulfonic acid is the linear isopropalamin sulfonate dodecylbenzene, which is available from Pilot Chemical Company, incorporated in Los Angeles, California, under the trade name "CALIMULSE PRS". It is possible that the alkylaromatic salt is in the novel formulation at a concentration of approximately 0.1 to 90 average weight. Preferably, the alkylaromatic sulfonic acid is in a concentration of about 8 average weight. A branched alcohol ethoxylate is included in accordance with the present invention in the form of a nonionic surfactant and a demulsifying detergent to reduce the emulsifying effects of the salt of an alkylaromatic sulphonic acid. Without wishing to be bound by any particular theory in describing the efficacy of the novel heavy oil remover, it is considered that the hydrophobic branched alcohol interacts with the hydrophobic medium of the alkylaromatic salt emulsifier. This weakens the potential emulsion of the alkylaromatic salt to a degree that oligominerals present in the water or residual fluids in the process equipment that is being cleaned electrolytically helps the demulsification of the heavy oils of the extractant cleaning mixture, promoting at the same time the recovery of heavy oils. A preferred branched alcohol ethoxylate according to the present invention is available from Tomah Products, Inc., a Milton, Wisconsin, company under the tradename "TEKSTIM 8741". The branching alcohol ethoxylate can be found in the novel formulation at a concentration of about 0.05 to 50 average weight. Preferably, the concentration of the branched alcohol ethoxylate is about 4 average weight.

An ethoxylated alkyl thiol is included in the novel formulation as a second surfactant and emulsifier coagent. This ingredient uses chemical sulfur to form an emulsifier with a particularly high affinity in order to penetrate the sediments of heavy oils at high levels of dilution in the presence of water and residual fluids contained in the process equipment being cleaned. In addition, the sulfhydryl functional groups can chemically link the hydrogen sulfide by reacting it to produce complex sulfur functional groups linked to the organic hydrophobe, then fixing the free hydrogen sulfide present in the heavy oil sediment and the vapor space of the hydrogen sulfide. process equipment that is being cleaned. The presence of ethoxylate / ethereal functional groups, which are not affected by the terminal reactions of the thiol functional group with hydrogen sulfide, ensures that a certain hydrophilicide persists after these reactions occur, and thereby allow the properties of surfactant agent of the ingredient. A preferred ethoxylated alkyl thiol is available from Burlington Chemical Company, a company in Burlington, North Carolina, under the tradename "BURCO TME." The ethoxylated alkyl thiol can be found in the novel formulation at a concentration of about 0.05 to 50 average weight. Preferably, the concentration of the ethoxylated alkyl thiol is about 8 average weight. Water is included in the present invention and constitutes the balance of the total weight of the mixture. In operation, the process equipment that is to be cleaned by the novel formulation is drained of process fluids. Subsequently, the equipment is turned off. Then, the novel heavy oil remover can be re-circulated, either pure or diluted, through the process equipment. Although the novel formulation can be used at ambient temperatures, the heavy oil removal rate can be accelerated by heating the circulating flow. It has been observed that the heavy oil remover according to the present invention is effective at a dilution rate of up to about 95 average weight of water. Finally, the heavy oil remover that circulates, after solubilizing the petroleum sediments and absorbing the toxic and acid gases, is recovered and the oil separation phase is started for a future procedure. EXAMPLE The following ingredients are mixed in the percentages of weight already indicated, in order to prepare a heavy oil remover according to the present invention. Then, the formulation is circulated through the process equipment that is going to be cleaned. After the heavy oil sediments are solubilized, the heavy oil remover solution is recovered and the latter are separated.

TABLE I HEAVY OIL REMOVER Ingredient Average weight dipropylene glycol mono N-butyl ether 5 mixture of methyl cocoate and 10-methyl-turbolate (1) petroleum naphthenic distillate solvent (2) 5 Salt of an 8-alkylaromatic sulphonic acid (3) branched alcohol ethoxylate (4) 4 Ethoxylated alkyl thiol (5) 3 Water 65 (1) DEGREEZ from Alzo, Inc. (2) EXXSOL D-60 from Exxon Chemical (3) CALIMULSE PRS from Pilot Chemical Company (4) TEKSTIM 8741 from Tomah Products, Inc. (5) BURCO TME from Burlington Chemical Company It is possible repeat the example obtaining a similar success substituting the ingredients and concentrations generally and specifically described in this document for those used in the previous example.

From the above description, a person skilled in the art can easily determine the essential characteristics of this invention and, without departing from its spirit or scope, can make various changes and / or modifications to adapt the invention to different uses and conditions.

Claims (12)

1. CLAIMS 1. A heavy oil remover containing: Approximately 0.1 to 0.9 average weight of dipropylene glycol mono N-butyl ether; Approximately from 1 to 99 percent of a mixture of methyl cocoate and methyl tursolate; Approximately from 0.1 to 75 average weight of naphthenic petroleum distillate solvent; Approximately from 0.1 to 90 weight average salt of an alkylaromatic sulphonic acid; Approximately 0.05 to 50 average weight of branched alcohol ethoxylate; Approximately 0.05 to 50 average weight of ethoxylated alkyl thiol; and the balance, water.
2. 2. The heavy oil remover according to claim 1, wherein the concentration of dipropylene glycol mono N-butyl ether is about 5 average weight.
3. 3. The heavy oil remover according to claim 2, wherein the concentration of a mixture of methyl cocoate and methyl-tursolate is about 10 average weight.
4. 4. The heavy oil remover according to claim 1, wherein the weight ratio of methyl cocono to methyl tursolate in the mixture of both compounds ranges from 60 to 40, to 40 to 60, approximately. The heavy oil remover according to Claim 1, wherein the concentration of naphthenic distillate petroleum solvent is about 5 average weight. 6. The heavy oil remover according to claim 1, wherein the salt concentration of alkylaromatic sulfonic acid is about 8 average weight. The heavy oil remover according to claim 1, wherein the alkylaromatic sulphonic acid salt is a linear sulfonic acid dodecylbenzene isopropylamine. The heavy oil remover according to Claim 1, wherein the branched alcohol ethoxylate concentration is about 4 average weight. The heavy oil remover according to Claim 1, wherein the concentration of ethoxylated alkyl thiol is about 3 average weight. 10. A heavy oil remover, which contains: Approximately 5 average weight of dipropylene glycol mono N-butyl ether; Approximately 10% of a mixture of methyl cocoate and methyl girasolate; Approximately 5 average weight of naphthenic petroleum distillate solvent; About 8 weight average salt of an alkylaromatic sulphonic acid; Approximately 4 average weight of branched alcohol ethoxylate; Approximately 3 average weight of ethoxylated alkyl thiol; and the balance, water. The heavy oil remover according to Claim 10, wherein the weight ratio of the methyl cocono to methyl tursolate in the mixture of both compounds ranges from 60 to 40, to 40 to 60, approximately. The heavy oil remover according to Claim 10, wherein the alkylaromatic sulphonic acid salt is a linear sulfonic acid dodecylbenzene isopropylamine.