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EP1618070A1 - A process for the recovery of methacrylic acid from its aqueous diluted solutions by reverse osmosis - Google Patents

A process for the recovery of methacrylic acid from its aqueous diluted solutions by reverse osmosis

Info

Publication number
EP1618070A1
EP1618070A1 EP04713044A EP04713044A EP1618070A1 EP 1618070 A1 EP1618070 A1 EP 1618070A1 EP 04713044 A EP04713044 A EP 04713044A EP 04713044 A EP04713044 A EP 04713044A EP 1618070 A1 EP1618070 A1 EP 1618070A1
Authority
EP
European Patent Office
Prior art keywords
ppm
methacrylic acid
water
range
reverse osmosis
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
EP04713044A
Other languages
German (de)
French (fr)
Inventor
Massimo Luperi
Marco Rigamonti
Vincenzo Redaelli
Maurizio Panetta
Dario Giudici
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Arkema France SA
Original Assignee
Arkema SA
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Arkema SA filed Critical Arkema SA
Publication of EP1618070A1 publication Critical patent/EP1618070A1/en
Ceased legal-status Critical Current

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D61/00—Processes of separation using semi-permeable membranes, e.g. dialysis, osmosis or ultrafiltration; Apparatus, accessories or auxiliary operations specially adapted therefor
    • B01D61/02—Reverse osmosis; Hyperfiltration ; Nanofiltration
    • B01D61/025—Reverse osmosis; Hyperfiltration
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D61/00—Processes of separation using semi-permeable membranes, e.g. dialysis, osmosis or ultrafiltration; Apparatus, accessories or auxiliary operations specially adapted therefor
    • B01D61/02—Reverse osmosis; Hyperfiltration ; Nanofiltration
    • B01D61/04—Feed pretreatment
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/44—Treatment of water, waste water, or sewage by dialysis, osmosis or reverse osmosis
    • C02F1/441—Treatment of water, waste water, or sewage by dialysis, osmosis or reverse osmosis by reverse osmosis
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2311/00—Details relating to membrane separation process operations and control
    • B01D2311/04—Specific process operations in the feed stream; Feed pretreatment
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2101/00—Nature of the contaminant
    • C02F2101/30—Organic compounds
    • C02F2101/34—Organic compounds containing oxygen
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2303/00—Specific treatment goals
    • C02F2303/16—Regeneration of sorbents, filters

Definitions

  • the present invention relates to a process for the treatment of water mainly containing as pollutants methacrylic acid (AMA) , methyl ⁇ -hydroxyisobutyrate and methanol, having a COD (Chemical Oxygen Demand expressed in mg/litre of 0 2 ) higher than 5,000 to give for 65-85% waters having a COD lower than 1,600 and for 15-35% waters having a COD higher than 20, 000.
  • AMA pollutants methacrylic acid
  • COD Chemical Oxygen Demand expressed in mg/litre of 0 2
  • 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 m 3 /h, preferably from 20 to 30 m 3 /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 ⁇ -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 NH 4 + 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 NH 4 + .
  • 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 .
  • An object of the present invention is a process for the
  • thacrylic acid preferably from 1,000 to 3,000 ppm, compri ⁇
  • a permeate (a) being about 65-85% of the initial flow, containing from 3 to 200 ppm,
  • step (A) the water at the end of step (A) must have a pH from 5 to 11,
  • water is between 3 and 5.
  • water to be treated has a
  • NaOH, KOH, ammonia, alkaline-earth oxides are examples of bases.
  • acids mineral acids, preferably sulphuric acid can be
  • the present invention relates to a pro ⁇
  • ppm of methacrylic acid preferably from 1,000 to 3,000 ppm
  • tyrate preferably from 20 to 700 ppm, having a COD between
  • 3,000 and 20,000 preferably from 5,000 to 12,000, a NH 4 + between 50 and 2.000 ppm, preferably from 100 to 800 ppm and
  • ammonia at temperatures from 15°C to 40°C, preferably from 25° to 30°C, to obtain a pH between 5 and 9,
  • a permeate (a) being about 65-85% of the initial flow, containing from 3 to 200 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 ⁇ -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 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 240 to 2,200 ppm, from 30 to 13,000 ppm of methyl a
  • 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 m 3 /h, more preferably from 15 to 30 m 3 /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 32.5 m 2 /module .
  • step (A) 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) .
  • 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 ⁇ -hydroxyisobutyrate is recycled in the process for obtaining MMA to give a further amount of methylmethacrylate .
  • Example 1 and the Example 3 have been respectively repeated but avoiding the treatment of the water with ammonia.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Water Supply & Treatment (AREA)
  • Nanotechnology (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Hydrology & Water Resources (AREA)
  • Environmental & Geological Engineering (AREA)
  • Organic Chemistry (AREA)
  • Separation Using Semi-Permeable Membranes (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)

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.

Description

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 α-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 15-35% 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 20 to 30 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 α-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, compri¬
sing:
(A) optional addition to the water of an acid or basic so¬
lution, 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 characteri¬
stics 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 pro¬
cess 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 α-hydroxyisobu-
tyrate, preferably from 20 to 700 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 initial flow, containing from 3 to 200 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 α-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 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 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. 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 30 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 32.5 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 α-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 30°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 8040 F type, having a filtering surface of 32.5 m2/modulus . For each Example two distinct flows are obtained: a permeate flow having the following characteristics:
and a concentrate 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 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.
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 α-hydroxyisobutyrate, preferably from 20 to 700 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, 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 200 ppm of methacrylic acid, preferably 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 α-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 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 240 to 2,200 ppm, from 30 to 13,000
ppm of methyl α-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.
EP04713044A 2003-02-25 2004-02-20 A process for the recovery of methacrylic acid from its aqueous diluted solutions by reverse osmosis Ceased EP1618070A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
ITMI20030329 ITMI20030329A1 (en) 2003-02-25 2003-02-25 METHACRYLIC ACID RECOVERY PROCESS FROM ITS DILUTED AQUEOUS SOLUTIONS BY REVERSE OSMOSIS.
PCT/EP2004/001683 WO2004076362A1 (en) 2003-02-25 2004-02-20 A process for the recovery of methacrylic acid from its aqueous diluted solutions by reverse osmosis

Publications (1)

Publication Number Publication Date
EP1618070A1 true EP1618070A1 (en) 2006-01-25

Family

ID=32923034

Family Applications (1)

Application Number Title Priority Date Filing Date
EP04713044A Ceased EP1618070A1 (en) 2003-02-25 2004-02-20 A process for the recovery of methacrylic acid from its aqueous diluted solutions by reverse osmosis

Country Status (5)

Country Link
EP (1) EP1618070A1 (en)
CN (1) CN100540476C (en)
BR (1) BRPI0407331B1 (en)
IT (1) ITMI20030329A1 (en)
WO (1) WO2004076362A1 (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114656638B (en) * 2022-03-03 2024-06-25 万华化学集团股份有限公司 A continuous synthesis method and device for polysulfone

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4022222A1 (en) * 1990-07-12 1992-01-16 Erdoelchemie Gmbh METHOD FOR PURIFYING ACRYLNITRILE WASTE WATER
JPH0724458A (en) * 1991-03-27 1995-01-27 Loctite Corp Method of treating waste water from process of cleaning by impregnation
JPH05131190A (en) * 1991-11-11 1993-05-28 Nitto Denko Corp Treatment of spent liquid containing acrylate-based substance
DE4410193A1 (en) * 1994-03-24 1995-09-28 Degussa Sealing of porous articles with curable impregnating fluid
CN1103749C (en) * 1997-03-14 2003-03-26 纳幕尔杜邦公司 A treatment method for wastewater containing organic acids
DE10113278A1 (en) * 2001-03-16 2002-09-19 Zahnradfabrik Friedrichshafen Pressure die-casting wash water purification involves reverse osmosis and membrane filtration to separate acrylates and methacrylates before ecologically acceptable directing to public drainage system

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO2004076362A1 *

Also Published As

Publication number Publication date
CN1750996A (en) 2006-03-22
ITMI20030329A1 (en) 2004-08-26
CN100540476C (en) 2009-09-16
BRPI0407331A (en) 2006-01-10
BRPI0407331B1 (en) 2013-03-19
WO2004076362A1 (en) 2004-09-10

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