SU686290A1 - Method of producing carbolic acids from oil shale - Google Patents

Abstract

1. METHOD FOR PRODUCING CARBON OUTPUT ACIDS FROM COMBUSTIBLE SHAFT by oxidizing it with nitric acid, characterized in that, for the purpose of simplification and cheapening of the process, shale with a content of 7 "/ o. Carbon 64-79 'Hydrogen 7.5-10Azot0.1-1.9Hetheroatoms 11-26 and oxidation is carried out with nitric acid of 20-70% concentration at a temperature of 20-24 ° C. The method according to claim 1, which is different from the fact that, in the process, use of crushed slate or concentrate of organic matter of slate.? C /)

Description

The invention relates to organic synthesis, specifically, to a process for the production of carboxylic acids from oil shale, which can be used in the production of plasticizers or plant growth stimulants.

There are known methods for producing carboxylic acids by oxidizing a concentrate of an organic substance of combustible shale with nitric acid of 20-30% concentration with or without pressure at a temperature of 105-1. Oxidation is carried out at a pressure of 50 to 100 atm (or without it), at a temperature of 105 -130 ° C for 4-8 h l or at a constant pressure or at least a pressure up to 200 ati, preferably 6-30 2. There is also known a method for producing carboxylic acids by oxidizing a concentrate of organic matter in shale with nitric acid and a medium concentrate at a high temperature of 2, L3J.

The closest to the technical essence and the achieved results is the method of obtaining carboxylic acidic oil shale by oxidizing the organic matter concentrate of shale with 98-99% nitric acid at atmospheric pressure and at a temperature of 30-80 0 d

The disadvantage of this method is the use in the process of highly concentrated nitric acid at a relatively high temperature. It is necessary for the implementation of the process of dosage in acid dry concentrate can lead to explosions and fires.

The purpose of the invention is to simplify and cheapen the process.

The goal is achieved by the described method of obtaining lsarboxylic acids from combustible shale, which use shale with a carbon content of 64-79%, 7.5-10% hydrogen, 0.1-1.9% azo-a and 11-26% heteroatoms. , usually crushed or in the form of an organic substance concentrate, which is subjected to oxidation with nitric acid of 20-70% concentration at a temperature of 20-24 ::.

The materials used as the source are characterized by the following indicators: 1. Cascier slate (Volzhsky

basin) of the lower layer j i. II pack II layer (ash 47.4%, mineral carbon dioxide 6.9% and total sulfur 5.0%). The elemental composition of organic matter,%: C 64.61 H 8.3, N 1.4; O, S and other heteroatoms 25,7.

2. A flotation concentrate of organic matter of Baltic shale oil was obtained from a shale of a drilling sample on June 21, 1972 by PDP uch. № 2, sat. lav 19-20, pack In the mine Sompa ESSR. The elemental composition of the organic matter of the concentrate,%: C 79.21; H 9.71, N traces; Oh and other heteroatoms 11,08.

3. Dictating shale taken from the northern part of the Maardu ESSR open pit in March 1975, average sample. The elemental composition of the organic matter of shale,%: C 74.7; H 7.6, N 1.9, S 2.5, - O 13.3

As a result of the oxidation of these shale, crude mixtures of dicarboxylic acids (DCC) are obtained, containing ci, coj-DCC, c-methyl-substituted DCC, mono-boronic and tricarboxylic acids, phenyl derivatives of monocarboxylic acids, and aromatic acids. The proposed oxidation method makes it possible to increase the content of higher homologues azelaic and sebic acids in the target product.

The separation of oxidation products and the regeneration of nitric acid is carried out by any known methods. The process yields oi, to di- and polycarboxylic acids, which can be used in organic synthesis and for the preparation of plant growth stimulants, as well as plasticizers.

At the same time, polycarboxylic acids (PFC) are separated according to the claimed method from oxidative degradation products, on the basis of their different solubilities in organic solvents compared to DCC.

In the inventive process, as a rule, the raw material is ground shale. In the method according to the prototype, it is necessary to use concentrates of organic matter of shale, which significantly complicates and increases the cost of the process. It should also be noted that in order to preserve the initial high concentration of nitric acid in the prototype, the concentrate should not contain moisture, which requires additional drying of the concentrate, which is obtained by wet methods, which, due to its high content of organic matter, is flammable. Most of the shale of the world is enriched very difficultly or hardly enriched. From this, the advantage of the claimed method is obvious. For comparison of the claimed method with the method of the prototype, the technology of separation and purification of raw DCCs should be chosen the same for both methods. In this case, you can expect almost the same costs for cleaning. However, in the proposed method is much larger compared to the prototype. The capacity of the reaction apparatus and the long duration of the process. These disadvantages are compensated by the fact that instead of the difficult-to-reach and expensive special steels required for reactors, the prototype can use cheap and affordable materials: vinyl plastic, ceramic plates. The consumption of nitric acid (calculated as 100%) in the inventive method and the prototype is almost the same with the same oxidation depth of the organic matter of oil shale. The expenses of nitric acid lost during the neutralization of residual nitric acid in the prototype and the acid consumed for neutralizing the carbonates of the mineral part of the oil shale in the claimed method are practically equal. At the same time, the price of concentrated varieties of nitric acid is lower than the 100% advantageous price of the claimed method. In addition, according to the claimed method, nitric acid is easier to regenerate, removing excess water. By steaming, while special procedures are required to obtain 100% nitric acid. In spite of the increase in the process time compared to the known ones, the proposed method allows di- and polycarboxylic acids without. pre-enrichment of oil shale, carry out the process under mild conditions (use of cheap viniplast coatings, simple containers), use nitric acid of medium concentrations as an oxidant (20-70%), which facilitates the regeneration of the latter, in the acids obtained by the proposed method , in large quantities there are higher homologues (azelaic and sebacic acid), which increases the value of acids as plasticizers. Example 1. Crushed shale crushed to 0.1 mm (ash 47.4%, mineral carbon dioxide 6.9%) is mixed with 50% nitric acid (1 kg per 10 liters of acid) and mixed periodically (1-2 times in weekly) for a month at room temperature TeNmepaType. The reaction solution is decanted, the insoluble precipitate is filtered and washed with water. Nitric acid is recovered from the filtrate and the washings by evaporation in vacuo. The content of low molecular weight and poly 1-psarboxylic acids is determined by the extraction of both the residue of evaporation and the insoluble oxidation products in the Soxhlett apparatus with ether and acetone. The yield of low molecular weight organic acids in the form of an ether extract of soluble products in wt.%: 33.5 insoluble - 3.5 (total 37.0). The output of polycarboxylic acids in the form of an acetone extract of soluble products is 15.0, insoluble - 31.2 (total 46.2). According to gas chromatographic analysis, the ether extracts contain l, s-dicarboxylic acids (50% are azelaic acid and its higher homologs). The selection of acids carried out by known methods. , Example 2. In analogy to Example 1, shale was oxidized with 20% nitric acid (1 kg of shale per 35 l of nitric acid), while nitration of calcium nitrate with impurities of magnesium and iron nitrates was obtained by heating the reaction solution. From insoluble oxidation products, 12% of carboxylic acids, mainly polycarboxylic acids, from shale organic matter were extracted. Example 3. Kashpirsky slate mixed with 70% nitric acid during the week with stirring 1 time per day. The oxidation products were investigated similarly to the products of example 1. The total yield of carboxylic acids was 92.6% of the organic matter of shale.

Example 4. A flotation concentrate of organic matter from Baltic shale oil (ash yield 13.8 and mineral carbon dioxide 2.4%) is mixed with 70% nitric acid and stirred for a month. 52.9% of low molecular weight acids and 33.2% polycarbonate ha of acids were obtained (a total of 86.1%).

Example 5. Lycthionic

Shale (ash ash 81.0, mineral carbon dioxide 0.2%) is treated at room temperature with 20% nitric acid for 1 day and then 70% for a week

(the ratio of the acid in examples 2 and 1). 16.6% of low molecular weight acids and 34.6% of polycarboxylic acids were obtained (a total of 51.2%).

Claims (2)

1. METHOD FOR PRODUCING CARBOXYLIC ACIDS FROM COMBUSTIVE SHALE by oxidizing it with nitric acid, characterized in that, in order to simplify and reduce the cost of the process, shale is used as the initial shale with the content,%: Carbon Hydrogen Nitrogen Heteroatoms 64-79 ' 7.5-10 0.1-1.9 11-26 and the oxidation is carried out with nitric acid of 20-70% concentration at a temperature of 20-24 C. 2. The method of pop. ^ characterized in that, in the process, crushed shale or a concentrate of organic matter of shale are used. SU, „, 686290