PROCESS FOR THE PURIFICATION OF EUGENOL AND NOVEL COMPOSITIONS COMPRISING EUGENOL
The present invention relates to a process for the purification of crude eugenol by distillation in the presence of at least one stabilizing compound. The process of the present invention may be operated industrially, exhibits improved properties, in particular in terms of process safety, and makes possible efficient separation of ortho-eugenol. The present invention also relates to compositions comprising eugenol.
1 . A process for the purification of eugenol, the process comprising distilling a crude eugenol containing impurities in the presence of at least one stabilizing compound.
2 . The process for the purification of eugenol as claimed in claim 1 , wherein the stabilizing compound is selected from the group consisting of phenol derivatives, phenothiazine derivatives, TEMPO derivatives, CB (copper dibutyldithiocarbamate), para-benzoquinone, para-phenylenediamine, diethylhydroxylamine, manganese(II) acetate, sodium nitrite, sodium ascorbate, potassium ascorbate, glutathione and bis(2,2,6,6-tetramethyl-4-piperidyl) sebacate.
3 . The process for the purification of eugenol as claimed in claim 1 , wherein the at least one stabilizing compound has a boiling point greater than the boiling point of eugenol.
4 . The process for the purification of eugenol as claimed in claim 1 , wherein the total amount of stabilizing compound is between 50 ppm and 10% by weight, with respect to the amount of eugenol.
5 . The process for the purification of eugenol as claimed in claim 1 , wherein eugenol is separated from ortho-eugenol.
6 . The process for the purification of eugenol as claimed in claim 1 , wherein the content of ortho-eugenol in the eugenol obtained is less than or equal to 10% by weight, with respect to the total weight of the composition.
7 . A process for the separation of eugenol and ortho-eugenol, the process comprising distillation in the presence of at least one stabilizing compound.
8 . A process for the manufacture of eugenol, the process comprising the purification process as defined in claim 1 .
9 . A composition comprising eugenol and between 0.05 and 10 000 ppm of at least one stabilizing compound, wherein the stabilizing compound is selected from the group consisting of phenol derivatives, phenothiazine derivatives, TEMPO derivatives, CB (copper dibutyldithiocarbamate), para-benzoquinone, para-phenylenediamine, diethylhydroxylamine, manganese(II) acetate, sodium nitrite, sodium ascorbate, potassium ascorbate and glutathione; and an auxiliary compound selected from the group consisting of vitamin E, butylated hydroxyanisole (BHA), dibutylated hydroxytoluene (BHT) and tert-butylhydroquinone (TBHQ).
10 . A composition comprising eugenol and between 0.05 and 10 000 ppm of at least one stabilizing compound and of an auxiliary compound, wherein the stabilizing compound is selected from the group consisting of phenol derivatives, phenothiazine derivatives, TEMPO derivatives, CB (copper dibutyldithiocarbamate), para-benzoquinone, para-phenylenediamine, diethylhydroxylamine, manganese(II) acetate, sodium nitrite, sodium ascorbate, potassium ascorbate and glutathione; and the auxiliary compound is selected from the group consisting of vitamin E, butylated hydroxyanisole (BHA), dibutylated hydroxytoluene (BHT), tert-butylhydroquinone (TBHQ) and bis(2,2,6,6-tetramethyl-4-piperidyl) sebacate.
11 . The composition as claimed in claim 9 , wherein the phenol derivative is a compound according to the following formula (IV):
wherein:
R represents a hydroxyl, a linear or branched alkyl, alkenyl, an alkoxy group a nitro group or a nitroso group,
R 2 represents a linear or branched alkyl, and
n is between 0 and 5.
12 . The composition as claimed in claim 9 , comprising at least 90% by weight of eugenol, with respect to the total weight of the composition.
13 . A composition comprising at least 90% by weight of eugenol and up to 10% by weight of ortho-eugenol, with respect to the total weight of the composition.
14 . The composition as claimed in claim 10 , wherein the phenol derivative is a compound according to the following formula (IV):
wherein:
R represents a hydroxyl, a linear or branched alkyl, alkenyl, an alkoxy group, a nitro group or a nitroso group,
R 2 represents a linear or branched alkyl, and
n is between 0 and 5.
15 . The composition as claimed in claim 10 , comprising at least 90% by weight of eugenol, with respect to the total weight of the composition.