Title of Invention	A PROCESS FOR THE RECOVERY OF METHACRYLIC ACID FROM ITS AQUEOUS DILUTED SOLUTIONS BY REVERSE OSMOSIS
Abstract	A process for the recovery of methacrylic acid (AMA) from aqueous solutions comprising from 500 to 5,000 ppm of methacrylic acid by: (A) optional addition to Said waters of an acid or basic solution, until obtaining a pH in the range 5-11; (B) feeding of the aqueous mixture obtained in (A) to a membrane or to a membrane system by osmosis, obtaining a permeate containing from 3 to 200 ppm of methacrylic arid and a concentrate containing from 1,000 to 35,000 ppm of methacrylic acid.

Title of Invention

A PROCESS FOR THE RECOVERY OF METHACRYLIC ACID FROM ITS AQUEOUS DILUTED SOLUTIONS BY REVERSE OSMOSIS

Abstract

A process for the recovery of methacrylic acid (AMA) from aqueous solutions comprising from 500 to 5,000 ppm of methacrylic acid by: (A) optional addition to Said waters of an acid or basic solution, until obtaining a pH in the range 5-11; (B) feeding of the aqueous mixture obtained in (A) to a membrane or to a membrane system by osmosis, obtaining a permeate containing from 3 to 200 ppm of methacrylic arid and a concentrate containing from 1,000 to 35,000 ppm of methacrylic acid.

Full Text	A PROCESS FOR THE RECOVERY OF METHACRYLIC ACID FROM ITS- AQUEOUS DILUTED SOLUTIONS BY REVERSE OSMOSIS ***** The present invention relates to a process for the treatment of water mainly containing as pollutants methacrylic acid (AMA) , methyl a-hydroxyisobutyrate and methanol, having a COD (Chemical Oxygen Demand expressed in mg/litre of 02) higher than 5,000 to give for 65-85% waters having a COD lower than 1,600 and for 15 -3 5 % waters having a COD higher than 20,000. It is known that in one of the process for the preparation of the methylmethacrylate (MMA), acetoncyanohydrin reacts with an excess of sulphuric acid and also is a solvent of the methacrylamide produced by the reaction. The obtained methacrylamide sulphate solution is subsequently subjected to esterification, in a column or in a series rector battery, with a methanol aqueous solution to give methylmethacrylate. The methylmethacrylate is separated from the mixture by stripping with vapour in counter-current from the column or from the series of reactors obtaining as a residue an aqueous solution of sulphuric acid containing ammonium bisulphate and organic by-products. The sulphuric acid of the residue is recovered as ammonium sulphate by neutralization with ammonia. The obtained solution formed of water, ammonium sulphate and organic byproducts, is fed to chrystallizers. After water evaporation, ammonium sulphate suspension is obtained. Ammonium sulphate is then separated by centrifugation. The condensed water evaporated from the chrystallizers has a flow-rate generally ranging from 5 to 50 m3/h, preferably from 2 0 to 3 0 m3/h and contains as main organic by-products generally from 1,000 to 3,000 ppm of methacrylic acid, from 20 to 700 ppm of methyl a-hydroxyisobutyrate, from 200 to 1,000 ppm of methanol and it has a COD in the range 5,000-12,000 and an ammonium concentration NH4* in the range 100-800 ppm. This water flow must be chemically treated before wasting them owing to its high COD content and the presence of ammonium NH4+. The chemical treatment to lower the COD under the law limits, is long and expensive due to the high water amount to be treated and the high cost of the necessary chemical reactants. The need was therefore felt to be able to dispose of said condensed water without using long and expensive treatments with chemical reactants. It has been found a simple, rapid and not expensive process allowing to separate from said condensed water most of the organic by-products, which are reused in the process for obtaining MMA, and a water having a low COD, disposable or reusable in the process for obtaining methylmethacrylate (MMA). An object of the present invention is a process for the treatment of water comprising from 500 to 5,000 ppm of me-thacrylic acid, preferably from 1,000 to 3,000 ppm, comprising: (A) optional addition to the water of an acid or basic solution, at temperatures from 15°C to 40°C, preferably from 25°C to 30°C, until obtaining a pH in the range 5-11, preferably 5.5-9; (B) feeding of the aqueous mixture obtained in (A) to a reverse osmosis membrane, or to a membrane system, by preferably having a polyamide basis with a polysulphone support, obtaining a permeate (a) , being about 65-85% of the initial flow, containing from 3 to 200 ppm, preferably from 5 to 45 ppm of methacrylic acid, and a concentrate (b), being about 15-35% of the initial flow, comprising from 1,000 to 35,000 ppm, preferably from 2,000 to 6,000 ppm of methacrylic acid. The Applicant has found that one of the main characteristics of the process of the present invention is that the water at the end of step (A) must have a pH from 5 to 11, preferably from 5.5 to 9. • Therefore in (A) a base is added when the pH of starting water is between 3 and 5. When the water to be treated has a pH higher than 5 up to 11, optionally an acid is added to bring the pH in the range 5-9. As bases, NaOH, KOH, ammonia, alkaline-earth oxides are used. As acids, mineral acids, preferably sulphuric acid can be used. More specifically the present invention relates to a process for the treatment of water comprising from 500 to 5,000 ppm of methacrylic acid, preferably from 1,000 to 3,000 ppm, from 100 to 3,000 ppm of methanol, preferably from 200 to 2,000 ppm, from 10 to 2,000 ppm of methyl a -hydroxy is obu-tyrate, preferably from 20 to 7 00 ppm, having a COD between 3,000 and 20,000, preferably from 5,000 to 12,000, a NH4+ between 50 and 2,000 ppm, preferably from 100 to 800 ppm and a pH in the range 3-5, preferably 3.5-4.5, comprising: (A) optional addition to the water of an aqueous solution of ammonia, at temperatures from 15°C to 40°C, preferably from 25° to 30 °C, to obtain a pH between 5 and 9, preferably between 5.5 and 7.5; (B) feeding of the aqueous mixture obtained in (A) to a reverse osmosis membrane, or a membrane system, preferably having a polyamide base on a polysulphone support, obtaining a permeate (a) , being about 65-85% of the ini t ial flow, containing from 3 to 2 00 ppm of methacrylic acid, preferaably from 5 to 45 ppm, from 80 to 2,800 ppm of methanol, preferably from 160 to 1,800 ppm, from 0 to 100 ppm of methyl a-hydroxyisobutyrate, preferably from 0 to 10 ppm and having a COD in the range 200-3,500, preferably 400-1,600, an ammonium ion concentration comprised between 2 and 20 0 ppm, preferably between 7 and 80 ppm, and a concentrate (b) , being about 15-35% of the initial flow comprising from 1,000 to 35,000 ppm of methacrylic acid, preferably from 2,000 to 6,000 ppm, from 120 to 3,200 ppm of methanol, preferably from 24 0 to 2,200 ppm, from 30 to 13,000 ppm of methyl a-hydroxyisobutyrate, preferably from 100 to 2,500 ppm, having a COD from 7,000 to 130,000, preferably from 20,000 to 60,000 and an ammonium ion content between 700 and 13,000 ppm, preferably between 2,000 and 4,000 ppm. Preferably the ammonia concentration in the solution in (A) is 15-25% by weight. In step (B) the feeding of the aqueous mixture obtained in (A) is preferably carried out by pressurization pumps, at a pressure of 5-70 bar, preferably 10-40 bar, more preferably 15-35 bar, with a flow from 5 to 50 m3/h, more preferably from 15 to 3 0 m3/h, to a wound spiral type reverse osmosis membranes collected in modules capable to separate molecules from 5 to 10 A, with a filtering surface of 3 2.5 m2/module. The Applicant has surprisingly and unexpectedly found that by treating the condensed water as described in step (A) and by using reverse osmosis membranes, it is separated an amount of methacrylic acid, and preferably also of methyl a-hydroxyisobutyrate higher than the amount separated without carrying out step (A) (see the comparative Examples), Examples of reverse osmosis membranes by are those available on the market of the BRACKISH WATER or SEA WATER type by DESAL. The permeate (a) can be recycled in the plant for preparing MMA as washing water or processing water or disposed as waste water. The concentrate (b) comprising methacrylic acid and methyl a-hydroxyisobutyrate is recycled in the process for obtaining MMA to give a further amount of methylmethacrylate. Some Examples follow for illustrative but not limitative purposes of the invention. EXAMPLES EXAMPLES 1-3 Condensed water flows having the following characteristics: are cooled to 3 0°C and treated with an aqueous solution of NH3 at 25% by weight until obtaining solutions having the following characteristics: Said solutions are subsequently filtered with a 20 micron cartridge filter, pressurized with centrifugal pumps up to 28 bar and fed to the reverse osmosis section constituted of 6 vessels containing each 6 membrane modules type polyamide wound spiral with polysulphone support, brackish water DESAL SE 8 04 0 F type, having a filtering surface of 32.5 mVmodulus. For each Example two distinct flows are obtained: a permeate flow having the following characteristics: EXAMPLES 4-5 (comparative) The Example 1 and the Example 3 have been respectively repeated but avoiding the treatment of the water with ammonia. ■ Said solutions are subsequently cooled, filtered and fed to the osmosis section as described in the Examples 1-3, obtaining for each example two distinct flows: a permeate having the following characteristics: and a concentrate having the following characteristics: CLAIMS A process for the treatment of water comprising from 500 to 5,000 ppm of methacrylic acid, preferably from 1,000 to 3,000 ppm, comprising: (A) optional addition to the waters of an acid or basic solution, at temperatures from 15°C to 40°C/ preferably from 25°C to 30°C, until obtaining a pH in the range 5-11, preferably 5.5-9; (B) feeding of the aqueous mixture obtained in (A) to a reverse osmosis membrane, or to a membrane system, preferably having a polyamide basis with a polysul-phone support, obtaining a permeate (a) , being about 65-85% of the initial flow, containing from 3 to 200 ppm, preferably from 5 to 45 ppm of methacrylic acid, and a concentrate (b) being about 15-35% of the initial flow, comprising from 1,000 to 35,000 ppm, preferably from 2,000 to 6,000 ppm of methacrylic acid. A process according to claim 1 for the treatment of water comprising from 500 to 5,000 ppm of methacrylic acid, preferably from 1,000 to 3,000 ppm, from 100 to 3,000 ppm of methanol, preferably from 200 to 2,000 ppm, from 10 to 2,000 ppm of methyl a-hydroxyisobutyrate, preferably from 20 to 700 ppm, having a COD between 3,00 0 and 20,000, preferably from 5,000 to 12,000, a NH4+ between 50 and 2.000 ppm, preferably from 100 to 800 ppm and a pH in the range 3-5, preferably 3.5-4.5, comprising: (A) optional addition to the water of an aqueous solution of ammonia, at temperatures from 15°C to 4 0°C, to obtain a pH between 5 and 9; (B) feeding of the aqueous mixture obtained in (A) to a reverse osmosis membrane, or a membrane system, preferably having a polyamide base on a polysulphone support, obtaining a permeate (a), being about 65-85% of the initial flow, containing from 3 to 20 0 ppm of methacrylic acid, preferably from 5 to 4 5 ppm, from 80 to 2,800 ppm of methanol, preferably from 160 to 1,800 ppm, from 0 to 100 ppm of methyl a-hydroxyisobutyrate, preferably from 0 to 10 ppm and having a COD in the range 200-3,500, preferably 400-1,600, an ammonium ion concentration comprised between 2 and 200 ppm, preferably between 7 and 8 0 ppm, and a concentrate (b) , being about 15-35% of the initial flow comprising from 1,000 to 35,000 ppm, of methacrylic acid, preferably from 2,000 to 6,000 ppm, from 120 to 3,2 00 ppm of methanol, preferably from 240 to 2,200 ppm, from 30 to 13,000 ppm of methyl a-hydroxyisobutyrate, preferably from 100 to 2,500 ppm, having a COD from 7,000 to 130,000, preferably from 20,000 to 60,000 and an ammonium ion content between 700 and 13,000 ppm, preferably between 2,000 and 4,000 ppm. A process according to claim 2, wherein in step (A) the water is additioned with the aqueous ammonia solution at a temperature in the range 25°C-30°C to obtain a pH in the range 5.5-7.5. A process according to claims 1-3, wherein in step (B) ■ the aqueous mixture is fed by pressurization pumps, at a pressure of 5-70 bar, preferably 10-40 bar, more preferably 15-35 bar, with a flow from 5 to 50 m3/h, preferably from 15 to 30 m3/h.

Full Text

A PROCESS FOR THE RECOVERY OF METHACRYLIC ACID FROM ITS-
AQUEOUS DILUTED SOLUTIONS BY REVERSE OSMOSIS
*****
The present invention relates to a process for the treatment of water mainly containing as pollutants methacrylic acid (AMA) , methyl a-hydroxyisobutyrate and methanol, having a COD (Chemical Oxygen Demand expressed in mg/litre of 02) higher than 5,000 to give for 65-85% waters having a COD lower than 1,600 and for 15 -3 5 % waters having a COD higher than 20,000.
It is known that in one of the process for the preparation of the methylmethacrylate (MMA), acetoncyanohydrin reacts with an excess of sulphuric acid and also is a solvent of the methacrylamide produced by the reaction. The obtained methacrylamide sulphate solution is subsequently subjected to esterification, in a column or in a series rector battery, with a methanol aqueous solution to give methylmethacrylate. The methylmethacrylate is separated from the mixture by stripping with vapour in counter-current from the column or from the series of reactors obtaining as a residue an aqueous solution of sulphuric acid containing ammonium bisulphate and organic by-products.
The sulphuric acid of the residue is recovered as

ammonium sulphate by neutralization with ammonia. The obtained solution formed of water, ammonium sulphate and organic byproducts, is fed to chrystallizers. After water evaporation, ammonium sulphate suspension is obtained. Ammonium sulphate is then separated by centrifugation.
The condensed water evaporated from the chrystallizers has a flow-rate generally ranging from 5 to 50 m3/h, preferably from 2 0 to 3 0 m3/h and contains as main organic by-products generally from 1,000 to 3,000 ppm of methacrylic acid, from 20 to 700 ppm of methyl a-hydroxyisobutyrate, from 200 to 1,000 ppm of methanol and it has a COD in the range 5,000-12,000 and an ammonium concentration NH4* in the range 100-800 ppm. This water flow must be chemically treated before wasting them owing to its high COD content and the presence of ammonium NH4+. The chemical treatment to lower the COD under the law limits, is long and expensive due to the high water amount to be treated and the high cost of the necessary chemical reactants.
The need was therefore felt to be able to dispose of said condensed water without using long and expensive treatments with chemical reactants.
It has been found a simple, rapid and not expensive process allowing to separate from said condensed water most of the organic by-products, which are reused in the process for

obtaining MMA, and a water having a low COD, disposable or reusable in the process for obtaining methylmethacrylate (MMA).
An object of the present invention is a process for the treatment of water comprising from 500 to 5,000 ppm of me-thacrylic acid, preferably from 1,000 to 3,000 ppm, comprising:
(A) optional addition to the water of an acid or basic solution, at temperatures from 15°C to 40°C, preferably from 25°C to 30°C, until obtaining a pH in the range 5-11, preferably 5.5-9;
(B) feeding of the aqueous mixture obtained in (A) to a reverse osmosis membrane, or to a membrane system, by preferably having a polyamide basis with a polysulphone support, obtaining a permeate (a) , being about 65-85% of the initial flow, containing from 3 to 200 ppm, preferably from 5 to 45 ppm of methacrylic acid, and a concentrate (b), being about 15-35% of the initial flow, comprising from 1,000 to 35,000 ppm, preferably from 2,000 to 6,000 ppm of methacrylic acid.
The Applicant has found that one of the main characteristics of the process of the present invention is that the water at the end of step (A) must have a pH from 5 to 11, preferably from 5.5 to 9.

• Therefore in (A) a base is added when the pH of starting water is between 3 and 5. When the water to be treated has a pH higher than 5 up to 11, optionally an acid is added to bring the pH in the range 5-9.
As bases, NaOH, KOH, ammonia, alkaline-earth oxides are used.
As acids, mineral acids, preferably sulphuric acid can be used.
More specifically the present invention relates to a process for the treatment of water comprising from 500 to 5,000 ppm of methacrylic acid, preferably from 1,000 to 3,000 ppm, from 100 to 3,000 ppm of methanol, preferably from 200 to 2,000 ppm, from 10 to 2,000 ppm of methyl a -hydroxy is obu-tyrate, preferably from 20 to 7 00 ppm, having a COD between 3,000 and 20,000, preferably from 5,000 to 12,000, a NH4+ between 50 and 2,000 ppm, preferably from 100 to 800 ppm and a pH in the range 3-5, preferably 3.5-4.5, comprising:
(A) optional addition to the water of an aqueous solution of ammonia, at temperatures from 15°C to 40°C, preferably from 25° to 30 °C, to obtain a pH between 5 and 9, preferably between 5.5 and 7.5;
(B) feeding of the aqueous mixture obtained in (A) to a reverse osmosis membrane, or a membrane system, preferably having a polyamide base on a polysulphone

support, obtaining a permeate (a) , being about 65-85% of the ini t ial flow, containing from 3 to 2 00 ppm of methacrylic acid, preferaably from 5 to 45 ppm, from 80 to 2,800 ppm of methanol, preferably from 160 to 1,800 ppm, from 0 to 100 ppm of methyl a-hydroxyisobutyrate, preferably from 0 to 10 ppm and having a COD in the range 200-3,500, preferably 400-1,600, an ammonium ion concentration comprised between 2 and 20 0 ppm, preferably between 7 and 80 ppm, and a concentrate (b) , being about 15-35% of the initial flow comprising from 1,000 to 35,000 ppm of methacrylic acid, preferably from 2,000 to 6,000 ppm, from 120 to 3,200 ppm of methanol, preferably from 24 0 to 2,200 ppm, from 30 to 13,000 ppm of methyl a-hydroxyisobutyrate, preferably from 100 to 2,500 ppm, having a COD from 7,000 to 130,000, preferably from 20,000 to 60,000 and an ammonium ion content between 700 and 13,000 ppm, preferably between 2,000 and 4,000 ppm. Preferably the ammonia concentration in the solution in (A) is 15-25% by weight.
In step (B) the feeding of the aqueous mixture obtained in (A) is preferably carried out by pressurization pumps, at a pressure of 5-70 bar, preferably 10-40 bar, more preferably 15-35 bar, with a flow from 5 to 50 m3/h, more preferably from 15 to 3 0 m3/h, to a wound spiral type reverse osmosis

membranes collected in modules capable to separate molecules from 5 to 10 A, with a filtering surface of 3 2.5 m2/module.
The Applicant has surprisingly and unexpectedly found that by treating the condensed water as described in step (A) and by using reverse osmosis membranes, it is separated an amount of methacrylic acid, and preferably also of methyl a-hydroxyisobutyrate higher than the amount separated without carrying out step (A) (see the comparative Examples),
Examples of reverse osmosis membranes by are those available on the market of the BRACKISH WATER or SEA WATER type by DESAL.
The permeate (a) can be recycled in the plant for preparing MMA as washing water or processing water or disposed as waste water.
The concentrate (b) comprising methacrylic acid and methyl a-hydroxyisobutyrate is recycled in the process for obtaining MMA to give a further amount of methylmethacrylate.
Some Examples follow for illustrative but not limitative purposes of the invention. EXAMPLES EXAMPLES 1-3
Condensed water flows having the following characteristics:

are cooled to 3 0°C and treated with an aqueous solution of NH3 at 25% by weight until obtaining solutions having the following characteristics:

Said solutions are subsequently filtered with a 20 micron cartridge filter, pressurized with centrifugal pumps up to 28 bar and fed to the reverse osmosis section constituted of 6 vessels containing each 6 membrane modules type polyamide

wound spiral with polysulphone support, brackish water DESAL SE 8 04 0 F type, having a filtering surface of 32.5 mVmodulus. For each Example two distinct flows are obtained: a permeate flow having the following characteristics:

EXAMPLES 4-5 (comparative)
The Example 1 and the Example 3 have been respectively repeated but avoiding the treatment of the water with ammonia.

■ Said solutions are subsequently cooled, filtered and fed to the osmosis section as described in the Examples 1-3, obtaining for each example two distinct flows: a permeate having the following characteristics:

and a concentrate having the following characteristics:

CLAIMS
A process for the treatment of water comprising from 500 to 5,000 ppm of methacrylic acid, preferably from 1,000 to 3,000 ppm, comprising:
(A) optional addition to the waters of an acid or basic solution, at temperatures from 15°C to 40°C/ preferably from 25°C to 30°C, until obtaining a pH in the range 5-11, preferably 5.5-9;
(B) feeding of the aqueous mixture obtained in (A) to a reverse osmosis membrane, or to a membrane system, preferably having a polyamide basis with a polysul-phone support, obtaining a permeate (a) , being about 65-85% of the initial flow, containing from 3 to 200 ppm, preferably from 5 to 45 ppm of methacrylic acid, and a concentrate (b) being about 15-35% of the initial flow, comprising from 1,000 to 35,000 ppm, preferably from 2,000 to 6,000 ppm of methacrylic acid.
A process according to claim 1 for the treatment of water comprising from 500 to 5,000 ppm of methacrylic acid, preferably from 1,000 to 3,000 ppm, from 100 to 3,000 ppm of methanol, preferably from 200 to 2,000 ppm, from 10 to 2,000 ppm of methyl a-hydroxyisobutyrate, preferably from 20 to 700 ppm, having a COD between 3,00 0 and 20,000,

preferably from 5,000 to 12,000, a NH4+ between 50 and 2.000 ppm, preferably from 100 to 800 ppm and a pH in the range 3-5, preferably 3.5-4.5, comprising:
(A) optional addition to the water of an aqueous solution of ammonia, at temperatures from 15°C to 4 0°C, to obtain a pH between 5 and 9;
(B) feeding of the aqueous mixture obtained in (A) to a reverse osmosis membrane, or a membrane system, preferably having a polyamide base on a polysulphone support, obtaining a permeate (a), being about 65-85% of the initial flow, containing from 3 to 20 0 ppm of methacrylic acid, preferably from 5 to 4 5 ppm, from 80 to 2,800 ppm of methanol, preferably from 160 to 1,800 ppm, from 0 to 100 ppm of methyl a-hydroxyisobutyrate, preferably from 0 to 10 ppm and having a COD in the range 200-3,500, preferably 400-1,600, an ammonium ion concentration comprised between 2 and 200 ppm, preferably between 7 and 8 0 ppm, and a concentrate (b) , being about 15-35% of the initial flow comprising from 1,000 to 35,000 ppm, of methacrylic acid, preferably from 2,000 to 6,000 ppm, from 120 to 3,2 00 ppm of methanol, preferably from 240 to 2,200 ppm, from 30 to 13,000 ppm of methyl a-hydroxyisobutyrate, preferably from

100 to 2,500 ppm, having a COD from 7,000 to 130,000, preferably from 20,000 to 60,000 and an ammonium ion content between 700 and 13,000 ppm, preferably between 2,000 and 4,000 ppm. A process according to claim 2, wherein in step (A) the water is additioned with the aqueous ammonia solution at a temperature in the range 25°C-30°C to obtain a pH in the range 5.5-7.5.
A process according to claims 1-3, wherein in step (B) ■ the aqueous mixture is fed by pressurization pumps, at a pressure of 5-70 bar, preferably 10-40 bar, more preferably 15-35 bar, with a flow from 5 to 50 m3/h, preferably from 15 to 30 m3/h.

Documents:

2000-chenp-2005 claims-duplicate.pdf

2000-chenp-2005 descritpion (complete)-duplicate.pdf

2000-chenp-2005-claims.pdf

2000-chenp-2005-correspondnece-others.pdf

2000-chenp-2005-description(complete).pdf

2000-chenp-2005-form 1.pdf

2000-chenp-2005-form 18.pdf

2000-chenp-2005-form 3.pdf

2000-chenp-2005-form 5.pdf

2000-chenp-2005-pct.pdf

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Patent Number

230020

Indian Patent Application Number

2000/CHENP/2005

PG Journal Number

13/2009

Publication Date

27-Mar-2009

Grant Date

24-Feb-2009

Date of Filing

23-Aug-2005

Name of Patentee

ARKEMA

Applicant Address

4-8 COURS MICHELET, F-92800 PUTEAUX,

Inventors:

#	Inventor's Name	Inventor's Address
1	LUPERI, MASSIMO	VIA LUCCA 12, I-20152 MILANO,
2	RIGAMONTI, MARCO	VIA BONNET 11, I-20154 MILANO,
3	REDAELLI, VINCENZO	VIA VERDI 10, I-20055 RENATE MILANO,
4	PANETTA, MAURIZIO	VIA SAN PIETRO 8B, I-20010 BAREGGIO MILANO,
5	GIUDICI, DARIO	VIA BORSI 5, I-20017 RHO MILANO,

PCT International Classification Number

C02F1/44

PCT International Application Number

PCT/EP04/01683

PCT International Filing date

2004-02-20

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1	MI2003A000329	2003-02-25	Italy