FR2488600A1 - HYDRATION OF PROPYLENE TO ISOPROPYLIC ALCOHOL ON SOLID SUPERACID CATALYSTS BASED ON PERFLUORINATED SULFONIC ACIDS - Google Patents

Abstract

THE INVENTION RELATES TO A PROCESS FOR HYDRATION OF LOWER OLEFINS TO A CORRESPONDING ALCOHOL, PROCESS CHARACTERIZED IN THAT IT CONSISTS OF REACTING OLEFINS WITH WATER IN THE PRESENCE OF A SOLID SUPERACID CATALYST BASED ON SULPHONIC ACID PERFLUORE.

Description

The invention relates to the hydration of propylene

  in isopropyl alcohol on superacid catalysts so-

  lides. One of the first petrochemical processes, which dates back to the early 1920s, was the hydration of propylene to isopropyl alcohol in a solution of sulfuric acid, in the context of a two-step process (esterification-hydrolysis) .

  The two-stage liquid phase process pre-

  there are, however, many serious disadvantages, for example

  ple the corrosive nature of 85% sulfuric acid required

  may be related to the propylene esterification reaction; the

  need to dilute the acidic reaction medium to favor

  ser hydrolysis and facilitate the separation of the acid from

  alcohol after hydrolysis, as well as the need for a re-

  concentration of the acid before recycling it to the stage

  process esterification; Finally, it is often necessary

  be able to neutralize the alcohol produced. As a result, the hy-

  direct dration of propylene on solid catalysts pre-

  feels of great practical importance to overcome these diff-

  difficulties. Significant work has therefore been carried out as part of the development of the propylene hydration program, which uses neither sulfuric acid nor any other acid in the liquid phase. The processes which have been studied generally involve bringing the olefin and water into contact in the presence of a suitable solid catalyst, at elevated temperature and pressure, so as to directly produce the desired isopropyl alcohol. The

  conversion to alcohol is favored by high pressures

  relatively low temperatures and a ratio

  high between steam and propylene.

  When the hydration catalyst is active at low temperature, the reaction usually takes place in the presence of a significant excess of liquid water (and therefore under high pressure). Kaiser, Beuther, Moore and Odioso (Ind. Eng. Chemistry Product Res. And Development, Vol. 1, p. 296 302 (1962)), using exchange resins

  of sulfonated styrene-divinylbenzene ions (e.g.

  ple Amberlyst 15 or Amberlite IR-120 from Rohm and Haas Co.) study the effects of temperature, pressure, space velocity and composition of the charge on the conversion rate and on the selectivity . when the catalyst used is not active at low temperature (<150 C), a vapor phase reaction is used to

  avoid extreme pressure. Thermodynamic balances

  ques that we see at high temperature limit the con-

  version-of propylene at very low percentages.

  Some of the hydration processes indicated used mineral or organic acids fixed on a support, and this in a relatively pressurized process

  low, mainly in the vapor phase, used for hydrata-

tion of propylene.

  Among the catalysts used, mention may be made of silicophosphoric acid (United States patent No. 2,876,266), phosphoric acid on a celite support (United States patent No. 2,579,601) and tungstic acid.

  on alumina support (F. J. Sanders and B. F. Dodge, Ind.

Eng. Chem., 26, 208 (1934)).

  The conversion rate indicated for operations in the vapor phase, for example on phosphoric acid fixed on a support of diatomaceous earth of the Celite brand at

  225 - 250 C at 550 psig (3.8 MPa) is only 3.8%.

  The direct hydration processes in the vapor phase eliminate the main difficulties of the two-step process in solution based on sulfuric acid but, until now, these processes had the advantage

  a low conversion rate per pass, which is known

  was supposed to be the result of the thermodynamic equilibrium conditions in the vapor phase. Research is therefore directed towards the use of conditions allowing reagents to be both in the vapor phase (propylene) and

liquid phase (water).

  Treatment with liquid water allows

  drive the olefins directly, at much higher conversion rates per pass than can be achieved in a vapor phase reaction, presumably because the solubility in water of the liquid phase alcohol produced changes the thermodynamic equilibrium, a consideration which limits conversion rates in the vapor phase. The catalysts that can be used in this

  mixed phase reaction must therefore have a stabili-

  hydrothermal tee in the presence of water in the liquid phase, at the required reaction temperature, as well as catalytic activity. The most frequently used catalyst for

  until now this reaction was tungs oxide-

  tene, although use of silica-alumina and Group VI and Group VII metals has also been reported

fixed on a support.

  Ogino ((Shokubai, Tokyo) 4, 73 (1962), Jo Catal., 8, 64 (1967)> found that metal sulfate-silica gel catalysts, especially those based on Fe, Al, Cr, Cu, Zn, Co, Pd, Ni, Mn, and the like, were active with respect to the hydration of propylene, and concluded that with these catalysts the range of acidities

  more suitable was between 1.5 and - 3 for H0.

  However, it should be considered that the methods used to define the surface acidity of the catalysts on the basis of color variations of the indicator dyes do not

  are unreliable. So there was no indication re-

  lative to what you would expect with cata-

  solid lysers with high acidity, in particular with

solid superacids.

  It has also been reported that sulfonated resins

  that cation exchangers were catalysts. Japanese patent application Kokai 77,151,106 (Chemical Abstracts 88, 169578x) discloses the use of hag resins

  cation exchangers, sulfonic acid type '-

  for the hydration of lower olefins, to form the corresponding alcohols. Example 1 of this patent application shows the hydration of propylene to form isopropyl alcohol, the catalyst used being chlorinated Ambezlyst, a sulfonated copolymer of divinylbenzin styrenes. The propylene conversion rate was 14.3%, the selectivity of isopropanol being 96%. The

  reaction required a temperature of 130 C and a pressure

  70 atm (6.9 MPa) o The same patent application claimed

  that also the use, as a catalyst of the resin Nafion 501 of Du PDnt, which is a copolymer of vinyl ether perfluorinated containing sulphonic radicals Example 2 shows the hydration of butene-1 with this catalyst, to form secondary butanol with a conversion rate of 3.1% o The explanation for this low conversion rate has not been given, but it is easy to imagine if we consider that the commercial Hafion 501 resin as used is the potassium salt of

  resin of the sulfonic acid type, and not an acid catalyst.

  As a result, the commercial Nafion resin, which is the potassium salt of the sulfonic acid type resin used in exchange membrane applications, does not =

  not come as a hydration catalyst.

  The invention is based on the discovery of lPap-

  titude of solid and super perfluorinated sulfonic acids

  acids to effectively analyze at temperatures

  low pressures and pressures, and even at atmospheric pressure

  spherical, hydration of lower olefins in C2 - C6,

  in particular the hydration of propylene into isopropyl alcohol

  pylic. These catalysts can be alkanesul-

  perfluorinated foniques in C10 C18; the free acid forms of the polymers of perfluorinated alkenesulfonic acids, for example the polymers of trifluoroethylenesulfonic acid,

  tetrafluoroethylene-trifluorethylene acid copolymers-

  sulfonic; or activated forms with free acidity of copolymers of perfluoralcene sulfonic acids and perfluorovinyl ethers, for example the free acid form of the commercial resins Nafion de du Pont de Nemours (called in this description Nafion-H). Catalysts according to

  the invention, based on perfluorinated sulfonic acids, presents

  an extremely low, if not zero, shade

  high bility for a long period under the hydration conditions used, which are due to the extremely high acidity, and which was not previously achieved by the solid catalyst systems, which leads to a

  high selectivity and good conversion rate.

  The temperature range of the hydra- reaction

  propylene catalyzed by a sulfonic acid per-

  fluorinated can vary between 120 and 180C, the molar ratio between water and propylene being between 1 and -50, the space velocity (VVH) in a static flow reactor being between 1 and 10. It turned out that the optimal conditions were as follows: a temperature between 140 and 1600C, a water / propylene molar ratio between 2 and 10, and a space speed between

  2.5 and 5. The flow can take place at atmospheric pressure

  risk or under pressure. It may be advantageous to use relatively low pressures (500 to 1,000 psi, or 3.45 - 6.9 MPa) to increase the yield of isopropyl alcohol per pass. The reaction preferably takes place on a catalyst in a fixed bed, in the vapor phase or in a mixed phase system. Under these conditions, a conversion of 15-30% of propylene into isopropyl alcohol is obtained by passing, with a selectivity of 96 to 99%. We can easily determine the optimal conditions for a

  hydration of other lower olefins.

  The perfluorinated solid alkane sulfonic acids used as catalysts according to the invention can be prepared by various methods, for example by the use of electrofluorination in the context of the preparation of the corresponding perfluorinated alkane sulfonyl fluorides, which can then be hydrolyzed into the corresponding alkanesulfonic acids, in accordance

  to JOURNAL OF THE CHEMICAL SOCIETY (London) 1947, p. 2640 -

  2645. Other methods of preparation include

  the reaction of perfluorinated alkyl iodides (RFI), by the

  through their Grignard reaction with sulfur dioxide or by the addition of sulfonyl halides to

perfluorinated olefins.

  Polymers of tri- acid can be prepared.

  fluorethylenesulfonic by different methods, in particular

  bind by hydrolysis, with water and a strong base (NaOH

  or KOH), polymers of trifluoroethylene fluoride-

  sulfonyl, according to U.S. Patent No. 3,041,317 (Chem. Absto, 58, 451a). Hydrolysis leads to the formation of alkaline salts of polymeric sulfonic acid, from which the active acid form is released by treatment with HNO3 or H2S040

  - We can prepare the same, according to the British patent

  pic no 1 184 321 (Chem. Abst. 73, 15936 V) of copolymers

  tetrafluoroethylene and trifluorethylenesulfonic acid

than.

  The ion exchange membranes of the Nafion brand, from du Pont de Nemours, for example the Nafion 501, are

  perfluorinated polymers having about 0.01 to 5 milliequiva-

  slow sulfonic acid groups per gram of catalyst.

  The polymeric resin is the potassium salt, which contains a repeating structure, which can be represented as follows:

CF3 CF

  1x (CF2CF) y 1 OCF2CF) m3 - C2 - F2) xt (CF2 - CF) y - (OCF 2CF) m - OCF2CF2 503 or CF 1 3 - (CF2 CF 2) x - (CF2- CF3) - ( OCF2 CF) m - OCF - CF3 'e

CF SO

3 3

  the ratio between x and y varies from about 2 to about 50, m being 1 or 2. The polymers having the above structure can be prepared in different ways. One of these methods, presented in US Patent No. 3,282,875 to Conolly et al., And in the patent

  No. 3,882,093 to Cavanaugh et al., com-

  takes the polymerization of perfluorinated vinyl compounds

  correspondents. It is also possible to prepare the ca-

  iO polymer polymer according to United States Patent No. 4,041,090, by copolymerizing perfluorinated vinyl ethers with

  perfluoroethylene and / or perfluoro-alpha-olefins.

  Commercial Nafion resins can be used

  vertices in their acid form (here called Nafion-H) by repeated treatment with strong acids in the aqueous phase,

  for example nitric acid or sulfuric acid.

  A superacid is an acid which, on the Hammett scale, has for H a value exceeding - 11, for example - 25, Thus, weaker acids like acid

  sulfuric (H - 11) or HF (Ho = - 10) are not part of it -

  tie. The invention will be better understood with regard to

  examples below. Although these examples use pre-

  References to propylene, the invention also applies to other olefins in general, and more particularly to lower olefins containing up to about six atoms.

of carbon.

EXAMPLE 1

  It was deposited by vacuum distillation on

  g of porous chromosorb 10 g of a perfluorhexade acid-

  canesulfonic C16F33503H. We introduced 5 g of this cat-

  lyser in a stainless steel catalyst tube reactor of dimensions 1TO'x 12 mmo This reactor was heated to 135 C and put under a pressure of 700 psig (4.8 MPa), and passed through through 8 g / h of propylene and 25 g / h of water. Isopropyl alcohol was obtained, with a propylene conversion rate of 23% and a selectivity

96%.

EXAMPLE 2

  Was deposited on 90 g of porous alumina 10 g of perfluorodacanesulfonic acid C1DF21SD3Ho LOon reacted 5 g of this catalyst under the conditions of Example 1, which gave a conversion rate of propylene into alcohol isopropyl 25%, with a selectivity of 97%.

EXAMPLE 3

  It was used as a catalyst, in the

  conditions of Example 1, 10 g of perfluorodod6- acid

  canesulfonic C12F25503H, which gave a conversion rate

  isopropyl alcohol 25% with selectivity

97%.

EXAMPLE 4

  - 10 g of the tri acid catalyst were introduced.

  polymeric fluorethylenesulfonic in a 150 x 8 mm fixed bed glass catalysis tube reactor. Was passed over the catalyst heated to 150 "C 10 g / h of propylene and 30 g / h of steam. The isopropyl alcohol obtained was obtained with a propylene conversion rate of 18%

and a selectivity of 96%.

EXAMPLE 5

  The reaction of Example 4 was resumed, but the catalyst used was a copolymer of tetrafluoroethylene and trifluoroethylene sulfonic acid. Isopropyl alcohol was obtained, with a conversion rate of the pro-

  15% pylene and 98% selectivity.

EXAMPLE 6

  It was heated at reflux for 2 hours in

  250 ml deionized water 50 g of Nafion-K resin from the

  0 merce (potassium salt of the ion exchange resin from the Société du Pont de Nemours). After filtration, the resin was treated for 5 hours at room temperature with ml of 20 - 25% nitric acid. After filtration,

  the nitric acid treatment was repeated three times.

  The resin was finally washed to neutrality with

  deionized water and then dried under vacuum at 105 ° C.

  within 24 hours. 5 g of the Nafion-H ac catalyst were placed.

  above in a glass tube catalyst reactor with a fixed bed, dimensions 150 x 8 mm. Was passed over the catalyst heated to 150 "C 10 g / h of propylene and 30 g / h of water. Isopropyl alcohol was obtained, with a propylene conversion rate of 16% and selectivity

97%.

EXAMPLE 7

  5 g of the Nafion-H pre-catalyst were introduced.

  adorned as in Example 5 in a fixed bed catalysis reactor in stainless steel of dimensions 170 × 12 mm. This reactor was heated to 130 ° C. and then, under a pressure of

  500 psig (3.45 MPa), it was passed through 8 g / h of pro-

  pylene and 125 g / h of water. The isopropyl alcohol obtained was obtained with a propylene conversion rate of 31% and a

96% selectivity.

  Of course, the invention is not limited to the embodiments described above and shown, from which other modes and other embodiments can be provided, without thereby departing from the scope of the invention .

Claims (5)

  1 - Hydration process of lower olefins in one   corresponding alcohol, process characterized in that it   is to treat ltol6fine or put it in contact with water, on an acid-based superacid catalyst   solid perfluorinated sulphonic, for a sufficient time   health to cause hydration of the olefin to a corresponding alcohol.   2 - Process for hydration of propylene into isopropyl alcohol   lique, characterized in that it consists in treating the pro- lo   pylon or to put it in contact with water, on a ca-   superacid talyser based on perfluorinated sulfonic acid   solid, for a time sufficient to cause hydra-   tation of propylene into isopropyl alcohol.   3 - Process according to claim 1, characterized in that it uses an acid-based superacid catalyst   C10 - C18 perfluorinated alkanesulfonic.   4 - Process according to claim 2, characterized in that it uses a superacid catalyst based on 2D alkanesulfonic acid perfluorinated in C10 - C18o   - Method according to any one of claims 1 or   2, characterized in that the catalyst used is a catalyst   superacid lyser consisting of a perfluorinated copolymer carrier of sulfonic groups.   6 - Method according to any one of claims 1 or   2, characterized in that the catalyst used is a co-   superacid lymer of tetrafluoroethylene and tri- acid fluorethylenesulfonic.