JPS6335616B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method for producing a molybdenum monocarboxylate organic compound containing almost no impurities.

[Conventional technology and its problems]

Conventionally known methods for producing molybdenum monocarboxylic acid include alkali metal salts of molybdic acid,
Methods are known in which alkaline earth metal salts, molybdenum halides, ammonium molybdate, molybdenum oxide, molybdenum oxide and ammonia, or mixtures thereof are reacted with monocarboxylic acids at 100 to 300°C (Tokuko Sho et al. 52−
50768), these raw materials, except for molybdenum trioxide, are salts of molybdic acid or halogen compounds. In the reaction of these compounds with monocarboxylic acid, salts or halides of the monocarboxylic acid and the base component of the raw material molybdate are inevitably produced as impurities, and it is not easy to remove these. do not have. For example, in the reaction with an alkali molybdate, an alkali monocarboxylic acid is produced as a by-product, and some of these also have properties as emulsifiers, and it is extremely difficult to remove them. Molybdenum oxide is known as a raw material that is not a salt and does not contain salt-forming impurities, but unfortunately the reactivity of this with monocarboxylic acids is extremely poor and this reaction lacks industrial practicality. .

[Purpose of the invention]

An object of the present invention is to provide a method for efficiently reacting molybdic acid and monocarboxylic acid and producing molybdenum monocarboxylate free of impurities.

[Structure of the invention]

In the present invention, without drying the molybdic acid produced by the precipitation method, the filtrate is treated with a concentrated sulfuric acid indicator solution of diphenylamine to the extent that it no longer shows a deep blue color.
Alternatively, there is a method for producing molybdenum monocarboxylate, which comprises washing with an indigo carmine solution to the extent that it maintains a blue color for 5 minutes, and then reacting it with a monocarboxylic acid under heat.

Currently, molybdic acid is produced by dissolving molybdenum trioxide in an alkali to make a molybdate salt, and then adding a strong acid to this solution to form molybdic acid crystals, which allows the reaction between molybdic acid and monocarboxylic acid to occur successfully. They discovered that the reason why molybdic acid was not produced was that it contained some inorganic acid that inhibited the reaction with monocarboxylic acid when making molybdic acid. By reacting, this reaction, which has rarely been carried out or has not been neglected, can be carried out industrially and efficiently, and it has been successfully produced to produce pure molybdenum monocarboxylate free of impurities. .

Once taken out as H ₂ MoO ₄ or H ₂ MoO ₄ .H ₂ O (dried), the inorganic acid is hardly removed no matter how many times it is washed with water. This is probably because the crystals are agglomerated, or perhaps the inorganic acid is incorporated into the crystallization water and cannot be removed by simple water washing. Focusing on this, before taking it out as a crystal and drying it, i.e. when it is wet with water, the filtrate remains blue with a concentrated sulfuric acid indicator solution of diphenylamine until it no longer shows a deep blue color, or with an indigo carmine solution for 5 minutes. It has been found that molybdic acid containing almost no inorganic acids and other impurities can be obtained by washing with water to a certain extent. Surprisingly, the reaction with the monocarboxylic acid using this equivalent amount of molybdic acid was almost 100% complete. Additionally, there is currently no known method for purifying molybdic acid by recrystallization.

The molybdenum monocarboxylate obtained by the process of the present invention is used as a catalyst in various reactions including the epoxidation of olefins such as propylene.

As the monocarboxylic acid used in the present invention,
Aliphatic monocarboxylic acids, alicyclic monocarboxylic acids, or aromatic monocarboxylic acids having 2 to 30 or more carbon atoms can be used.

That is, lower fatty acids such as acetic acid, propylene acid, butanoic acid, pentanoic acid, hexanoic acid, intermediate fatty acids such as enanthic acid, octanoic acid, 2-ethylhexanoic acid, caprylic acid, capric acid, lauric acid, palmitic acid, and oleic acid. Higher fatty acids such as cyclopentanoic acid, cyclohexanoic acid, cyclocapric acid, or cycloaliphatic monocarboxylic acids such as naphthenic acid, or benzoic acid, mono- or di-naphthoic acid, o-, m- or p-toluic acid, phenyl Aromatic carboxylic acids such as acetic acid may be used.

Furthermore, since the reaction between monocarboxylic acid and molybdic acid in the present invention is carried out very easily and quantitatively, the reaction can be carried out using equimolar amounts of both, and the reaction temperature is between 150°C and 280°C, particularly. 220
Preferably, it is carried out at a temperature within the range of -230°C. The reaction is carried out using an inert solvent such as propylbenzene (BP 159°C), cumene (BP 152°C), trimethylbenzene (BP 165°C to 176°C), or decane (BP 174°C), or a mixture thereof, or a boiling point It may be carried out in a petroleum solvent at a temperature of 150°C or higher.

Furthermore, when the reaction product is used as a catalyst or the like, the reaction product can be used as it is without being separated from the solvent.

Next, examples of the present invention will be described.

Example 1 220g of molybdenum trioxide was added to 600g of water,
Drop 192g of 28% ammonia water and stir while heating gently until the liquid becomes clear, then add 61% nitric acid.
After adding 220gr dropwise and stirring for about 5 hours under heating,
When the mixture was cooled to room temperature and left for 12 hours, crystals of molybdic acid precipitated at the bottom of the reaction vessel. Discard the supernatant liquid, add 1500 c.c. of distilled water, leave to stir, and separate the precipitate. After repeating the operation four times, separate the molybdic acid and add water to the separated molybdic acid on the paper. After pouring and washing with water, the filtrate was immediately thoroughly washed with water using a concentrated sulfuric acid indicator solution of diphenylamine until it no longer showed a deep blue color, or with an indigo carmine solution until it remained blue for 5 minutes, and then dried at a low temperature.

200 gr of molybdic acid H ₂ MoO ₄ obtained by this method and 627 gr of naphthenic acid with an acid value of 221.1 were mixed with a petroleum solvent (manufactured by Ciel Chemical: trade name: Loose, bp 155°C to 194° C.
C) 200gr and heated and stirred at 220 DEG C. to 230 DEG C. for about 12 hours. Unreacted molybdic acid was filtered off and removed to obtain a solution of molybdenum naphthenate containing 11.6% Mo.

Also, unreacted molybdic acid obtained by filtration
H ₂ MoO ₄ was 9.8 gr. That is, the reaction rate with respect to the molybdic acid used was 95.1%.

Example 2 Molybdic acid obtained by the same method as Example 1
H ₂ MoO ₄ 200gr and 2-ethylhexylic acid 356gr
was mixed with 680 gr of petroleum solvent and reacted in the same manner as in Example 1 to obtain a solution of molybdenum 2-ethylhexoate containing 9.8% Mo.

Further, unreacted molybdic acid H ₂ MoO ₄ was 4 gr. In other words, the reaction rate for the molybdenum used is
It was 98%.

Example 3 Instead of naphthenic acid in Example 1, the same number of moles of butanoic acid, caprylic acid, or oleic acid was used to react with molybdic acid in the same manner as in Example 1.
Molybdenum salts of each acid were obtained at almost the same reaction rate as in Example 1.

Comparative example Commercially available molybdenum trioxide MoO ₃ 72gr, acid value 221.1
254g of naphthenic acid and 200g of petroleum solvent were mixed and reacted in the same manner as in Example 1 to obtain a solution of molybdenum naphthenate containing 0.3% Mo.

Unreacted molybdenum trioxide MoO ₃ was 70 gr, ie, the reaction rate with respect to the molybdenum trioxide used was only 28%.

Claims (1)

[Claims] 1. Without drying the molybdic acid produced by the precipitation method, wash it with water until the filtrate no longer shows a deep blue color with a concentrated sulfuric acid indicator solution of diphenylamine, or until it remains blue for 5 minutes with an indigo carmine solution, and then dissolve the monocarboxylic acid. A method for producing molybdenum monocarboxylate, which comprises reacting with an acid under heat.