Process for the production of lubricants for cosmetics

Abstract

A process for the production of lubricants for cosmetic use is described. According to the present invention, waste oils of biological origin are transesterified with terpene alcohols. From an economic point of view, these waste oils are advantageously chosen from used cooking oils (UCO) and / or reclaimed used cooking oils (RUCO). Preferably, said terpene alcohols are chosen from the group consisting of menthol, geraniol, citronellol, nerolidol, linalool.

Description

[0001] PROCESS FOR THE PRODUCTION OF LUBRICANTS FOR COSMETICS DESCRIPTION

[0002] The present invention relates to the production of lubricants , in particular to the production of lubricants for use in the cosmetics field .

[0003] The use of lubricants has been known per se since time immemorial, in the most diverse areas of our lives . Lubricants are used mainly in mechanics , but also in the preparation of drugs , cosmetics and in other fields . In particular, in the mechanical field, the use of lubricants sub jects them to high temperatures and considerable friction, with the result that their chemical structure is altered by means of reactions involving cracking, mostly due to thermal action, coupling (by means of free radical and thermal action) , dehydration and dehydrogenation . In any case, these changes in their chemical nature seriously damage the properties of lubricants , altering important physical characteristics , such as viscosity, and making them increasingly unsuitable for the use for which they were produced . It should be added that , notwithstanding that lubricants reduce the mutual friction of moving parts , they do not eliminate it completely; under these conditions , small particles may detach from the moving parts by mechanical action, thus producing contamination of the oil with particles , mostly consisting of metallic and / or plastic material , which increase friction in an undesirable way . Both of these phenomena deteriorate the quality of the lubricant . In the long run, the lubricant , rather than being beneficial , risks becoming harmful to the machine in which it is used . For this reason, it is necessary to change the oil periodically, so as to always have efficient lubrication .

[0004] Changing the oil results in quantities of waste lubricant that do not have any immediate use and must therefore be disposed of . Inasmuch as these are substances that are pollutants for water and soil, disposal must not lead to their accumulation in these environments .

[0005] After a time in which it was preferred to use these substances as fuels , a move was made to regenerate waste oils , collecting them thanks to mandatory consortia, treating them appropriately and reintroducing them onto the market , with both economic and ecological benefits .

[0006] Recently, bio-based lubricants have been added to mineralbased lubricants ; these products are often called biolubricants . In contrast to mineral-based lubricants , which are mostly hydrocarbons , bio-lubricants are generally fatty acid esters . Normally, the alcohol component is a synthetic alcohol , such as methanol . These bio-lubricants also undergo the same trans formations as mineral-based lubricants and must be replaced . Even though their toxicity level is significantly lower than that of mineral oils ( sometimes they are even commonly used food substances ) , it is nevertheless a good idea to regenerate these oils too , to avoid their accumulation in the sewers , which can lead to phenomena such as the so-called " fatbergs" that can clog and cause sewage systems to burst .

[0007] Various processes have been studied to regenerate biolubricants , often separating them from other waste lubricants , with which they are frequently mixed during the collection of the waste material .

[0008] As mentioned, lubricants are also used in the cosmetics field . Such lubricants must be biocompatible and not be harmful to the skin and the body in general , and, to be good for cosmetic use , must be pleasant to smell and touch . This in itself requires rather expensive production methods and the use of mostly noble raw materials .

[0009] CN 116 925 853 discloses a method for the production of biodiesel by recovering grease from kitchen waste . The method involves hot water washing, centrifugation, sedimentation and vacuum dehydration; an esterification reaction with methanol; an oil-water separation; dehydration of the oil obtained; transesterification of the product with methanol ; centrifugation; distillation and neutralisation . The method does not , however, allow for a compound suitable for cosmetics to be obtained . FR 2 132 511 discloses a hair spray containing citronellyl senecionate . However, it does not disclose how to obtain cosmetic products from waste fats .

[0010] The problem underlying the invention is to propose a process for the production of lubricants for cosmetic use that overcomes the aforementioned drawbacks and that allows products perfectly suitable for use to be obtained, at low costs and with savings on raw materials . This obj ect is achieved through a process for the production of lubricants for cosmetic use , characterised in that oils of biological origin are transesterif led with terpene alcohols . The subclaims describe preferred features of the invention .

[0011] According to one embodiment , such oils of biological origin are waste oils . According to one embodiment , said waste oils are chosen from used cooking oils (UCO) and / or reclaimed used cooking oils (RUCO) .

[0012] According to one embodiment , waste oils also contain animal fats .

[0013] According to one embodiment , the waste oils originate from the biological fraction contained in a mixture of oils to be regenerated .

[0014] According to one embodiment , said waste oils of biological origin are first extracted from a mixture of waste oils with a polar solvent and then transesterif led with terpene alcohols .

[0015] According to one embodiment , said polar solvent is selected from methanol , ethanol, polyvinylpyrrolidone .

[0016] According to one embodiment , said terpene alcohols are selected from the group consisting of menthol , geraniol , citronellol , nerolidol, linalool, 1 , 4-butanediol .

[0017] According to one embodiment , L-menthol is used as the terpene alcohol .

[0018] According to one embodiment , the transesterification reaction occurs in the presence of a homogeneous catalyst .

[0019] According to one embodiment , the transesterification reaction occurs in the presence of a coordination compound . Preferably, the coordination compound is a titanium coordination compound .

[0020] According to one embodiment , the transesterification reaction occurs in the presence of titanium isopropoxide .

[0021] According to one embodiment , the transesterification reaction occurs in the presence of a strong base . Preferably, NaOH, KOH, CaO are used as strong bases .

[0022] According to one embodiment , the transesterification reaction occurs in the presence of a strong acid . Preferably, HC1 , HNO3, H2SO4 , HCIO4, trifluoroacetic acid are used as strong acids .

[0023] According to one embodiment , the transesterification reaction is carried out at a temperature between 120 and 220 °C . Preferably, this temperature is 180 ° C .

[0024] As mentioned, the present invention provides that waste oils of biological origin are extracted with a polar solvent from a mixture of waste oils and then are transesterif led with terpene alcohols . This allows for lubricants that also have a pleasant smell .

[0025] Oils of a biological origin, in fact , are mostly esters (mostly triglycerides ) of so-called fatty acids , which is to say, long-chain acids . In various methods , also developed by the Applicant , the waste oils of biological nature are extracted with polar solvents from the mixture of lubricants containing them, such as methanol, ethanol , polyvinylpyrrolidone and others , in order to remove them from the mixture of waste oils and from any washing water and to be able to subsequently treat them separately, so as to have good yields .

[0026] The transesterification reaction, widely known in chemistry and in industrial chemistry, consists in the substitution of an alcohol in an ester with another alcohol, in order to obtain a dif ferent product .

[0027] Like esterification reactions , transesterification reactions normally require the use of small amounts of acids or bases as catalysts . In any case, the species used to catalyse the transesterification are strong acids or bases , such as HC1 , HNO3, H2SO4 , HCIO4 , NaOH, KOH and the like . In substance , you have the reaction of removal of the alcohol from the ester, returning to the acid or acid salt and then the subsequent esterification with another alcohol . The reaction is well known in the literature and requires no further explanation .

[0028] The surprising discovery underlying the present invention is that the transesterification of waste , discarded oils , such as , for example , so-called UCO and RUCO (used cooking oils and reclaimed used cooking oils ) , which is to say waste that is often also smelly, if extracted and then transesterif led with terpene alcohols , leads to substances that , in addition to being lubricants , also have a pleasant or very pleasant scent and, therefore , can be used in cosmetics and perfumery, while maintaining perfect safety and with notable advantages .

[0029] To do this , the waste fats , once extracted from the mixture , are treated in an acidic environment with terpene alcohols . Among these, by way of example, menthol ( in particular, L-menthol ) , geraniol, citronellol , nerolidol, linalool, 1 , 4-butanediol can be mentioned . At the end of the reaction, the products maintain their lubricating properties , but lose their unpleasant odours and take on the pleasant smells of terpene alcohols .

[0030] Particularly favorable results were obtained by subjecting the waste oils to a reaction with methanol , arriving at methyl esters , and then with terpene alcohols . In this way, the reaction yields are higher and the products are purer .

[0031] Owed to this invention, it is possible to transform a waste product , an element of refuse, often also smelly, into a scented lubricating product , suitable for use in cosmetics .

[0032] In the following, an example is shown to evaluate the effects of the present invention . This example is not to be construed as limiting of the scope of the present invention, but rather is given for illustrative purposes only .

[0033] EXAMPLE

[0034] Waste edible oils are esterified with L-menthol . Used cooking oils are sub jected to treatment with methanol in an alkaline environment , with a mixture of methanol and NaOH . The product obtained is purified in a known way .

[0035] The methyl esters obtained in this manner are subj ected to a transesterification reaction . The methyl esters are n contacted with L-menthol , in the presence of titanium isopropoxide as a catalyst . To completely remove methanol , the reaction is carried out at 180 °C under a nitrogen flow .

[0036] The reaction product is subj ected to a fatty acid distillation programme .

[0037] The resulting product ( internal reference : BL119D) exhibits the following characteristics :

[0038] The product has lubricating characteristics , is scented with a mint fragrance and is completely biological and does not cause the accumulation of waste in the environment , not even during its disposal .

[0039] As can be seen, the present invention allows to obtain effective lubricants , particularly suitable for use in cosmetics , which are perfumed, perfectly compatible with the environment , with low costs , while at the same time allowing the disposal of waste oils and greases which could, instead, create problems , in particular at the level of sewer management . These lubricants are , moreover, completely biological in origin, with obvious benefits for health and the environment . It is to be understood, however, that the invention is not to be considered limited to the particular arrangement illustrated above, which is only an embodiment example of it , but rather that several variations are possible , all within the reach of a person skilled in the art , without hereby going beyond the scope of protection of the invention itself , as defined by the following claims .

Claims

CLAIMS1) Process for the production of lubricants for cosmetic use, characterised in that oils of biological origin are transesterif led with terpene alcohol.2) Process as in claim 1) , characterised in that said oils are waste oils.3) Process as in claim 2) , characterised in that said waste oils are chosen from used cooking oils (UCO) and / or reclaimed used cooking oils (RUCO) .4) Process as in claim 2) , characterised in that said waste oils of biological origin are previously extracted from a mixture of waste oils with a polar solvent and are then transesterif led with terpene alcohols.5) Process as in claim 4) , characterised in that said polar solvent is chosen from methanol, ethanol, polyvinylpyrrolidone .6) Process as in any one of the preceding claims, characterised in that said terpene alcohols are selected from the group consisting of menthol, geraniol, citronellol, nerolidol, linalool, 1 , 4-butanediol .7) Process as in claim 6) , characterised in that L-menthol is used as terpene alcohol.8) Process as in any one of the preceding claims, characterised in that the transesterification reaction occurs in the presence of titanium isopropoxide .9) Process as in any one of the preceding claims, characterised in that the transesterification reaction is carried out at a temperature between 120 and 220 °C.

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