RU1751901C - Method of producing flotation agent - Google Patents

Abstract

FIELD: chemical engineering. SUBSTANCE: pertinacious hydrolyzate of endocrine production process wastes or waste culture fluid of paprine production process are subjected to interaction with higher aliphatic oxiranes C₉-C₁₆ in water-alcohol medium. Reaction mixture is heated at 75-80 C or boiled with stirring for 5-6 h, then acidified up to pH 2, extracted with ethylacetate, and the desired product is separated. Flotation agent produced allows a quality apatite concentrate with optimum foaming properties to be obtained. EFFECT: quality flotation agent having optimum foaming properties. 3 tbl

Description

 The invention relates to chemical technology, in particular to a method for producing a flotation agent based on a protein raw material hydrolyzate, which is introduced into interaction with oxiranes of higher olefins. The specified reagent is a mixture of N-substituted amino acids, belongs to the class of surface-active substances (surfactants) and is an effective collector for the flotation of phosphate ores.

 The proposed method for producing a flotation reagent consists in the fact that a protein raw material hydrolyzate (type A) or an amino acid complex of the spent culture fluid produced by paprine (type B) interacts with a mixture of higher aliphatic 1-alkene oxiranes to form N-hydroxyalkyl derivatives of amino acids.

 Known methods for producing surfactants such as N-hydroxyalkylamino acids using aliphatic oxiranes.

 It is also known to use N-acylamino acids based on proteinaceous feedstocks as a flotation reagent.

 However, achieving sufficiently high performance when using such an agent as a collector for flotation of poor apatite-silicate ores of complex composition is difficult due to abundant foaming, which complicates the process and makes it unstable.

 The purpose of the invention is the improvement of flotation properties of the target product.

The reagent is prepared by reacting higher oxiranes with a mixture of amino acids of type A or B, which is carried out by boiling in an aqueous-alcoholic solution under an alkaline reaction of the medium (pH9) for 5-6 hours. A mixture of oxiranes of aliphatic 1-alkenes C ₉ -C _{16 of the} following was used in the reaction composition, wt. %: C ₉ 4, C ₁₀ 19, C ₁₁ 5, C ₁₂ 6, C ₁₃ 6, C ₁₄ 50, C ₁₅ 6, C ₁₆ 4. The products were isolated by acidification of the reaction mixture to pH 1-2, extraction with water-alcohol solution of the product with ethyl acetate, the organic layer was separated, washed with water until neutral, evaporated in vacuo, dried and the acid form of the reagent was obtained.

 An analysis of the composition of the initial mixture of oxiranes and analytical control of the course of the reaction was carried out by high-performance liquid chromatography in reverse phases (by conversion of the starting oxiranes). The quality of the products was determined by potentiometric titration in glacial acetic acid (the method was developed at the Moscow Art Institute named after Mendeleev to determine amino groups of various degrees of substitution).

Hydrolysates of protein raw materials (waste from endocrine production) or a complex of amino acids obtained from used culture fluid of paprin production were used as starting materials containing amino acids. The starting amino acids were obtained by alkaline hydrolysis of the proteinaceous feed or from the culture fluid (for the reaction, the latter were converted to the salt form). The analysis of the initial mixtures of amino acids was carried out by ¹³ C NMR. A specially developed method consists in preliminary calibration of the external standard on artificial mixtures of amino acids with the accumulation of signals in ¹³ C NMR spectra and subsequent processing of the spectra using appropriate computer programs. Data on the composition of mixtures of amino acids used to obtain the reagents are given in table. 1.

 Obtaining flotation reagents described in examples 1-2.

 PRI me R 1. A. Hydrolysis of protein raw materials.

In a three-necked flask equipped with a reflux condenser and a stirrer, 10 g of peptone B, 8.5 g (213 mmol) of sodium hydroxide and 25 cm ^{3 of} distilled water are charged. The mixture is boiled with stirring for 12 hours, the insoluble residue (oligopeptides) is filtered off, the aqueous solution of the amino acid salts is evaporated in vacuo, dried, and 17.6 g of alkaline peptone B hydrolyzate are obtained (average molecular weight 140, the amino acid composition is given in Table 1 )

 B. Obtaining flotation reagent.

In a three-necked flask equipped with a stirrer and reflux condenser, 4.55 g (23 mmol) of a mixture of C ₉ -C ₁₆ oxiranes in 20 ml of isopropyl alcohol and 4.1 g (29.3 mmol) of alkaline hydrolyzate obtained in stage A are charged, in 15 ml of water. The reaction mixture (pH 10-11) is boiled with stirring for 5 hours. The complete conversion of the starting oxiranes is shown by HPLC.

 Then the reaction mixture was acidified with HCl (decomp. 1: 3) to pH 2, poured with 50 ml of water and transferred to a separatory funnel. It is extracted with ethyl acetate (2x50 ml), the extract is washed with water until neutral, dried over sodium sulfate, evaporated in vacuo and 5.36 g of product 1A are obtained.

Example 2. Under the conditions of Example 1, 3.64 g (18 mmol) of a mixture of C ₉ -C ₁₆ oxiranes in 20 ml of ethanol and 2.7 g (22.7 mmol) of the amino acid complex of the spent culture fluid are reacted in 10 ml of water (pH of the reaction mixture of 9-10 adjusted by the addition of 1.3 g of KOH) and stirred while heating to 75-80 ^{° C} for 6 hours to complete conversion of the oxiranes. 4.5 g of product 1B are similarly isolated from the resulting reaction mass.

The completeness of the reaction and the quality of the obtained products were evaluated by potentiometric titration of a solution of the reaction mixture or reaction product in glacial acetic acid (determination of amino groups of different substitutions). The following is an example of the determination of primary and secondary amino groups in the condensation product of higher C ₉ -C ₁₆ oxiranes and amino acids of the endocrine waste hydrolyzate (Example 1).

Two aliquots of 10 ml of the analyzed solution of product 1A in ice-cold AcOH (T 0.02 g / ml) were taken into 100 ml titration beakers. The first 1 ml aliquot surged salicylaldehyde glass and placed in a water bath (40-50 ^{° C,} 10 min), covering it with a watch glass. Then, 10 ml of dioxane was added to the sample (improves the shape of the titration curves) and titrated with 0.1 N a solution of HclO ₄ in dioxane (V ₁ 6 ml). Since the primary amino groups of unreacted amino acids are bonded to Schiff bases, only the secondary amino groups of the condensation product are titrated. 10 ml of dioxane were added to a second aliquot and titrated with 0.1 N. a solution of HclO ₄ in dioxane (V ₂ 6.3 ml). The volume of V ₂ corresponds to the sum of the primary amino groups of the unreacted amino acids of the hydrolyzate and the amino groups of the reaction product. Thus, the ratio of the volumes of V ₁ and V ₂ can be judged on the purity of the obtained product. In this case, it is 0.95, which corresponds to 95% of the amino groups formed during the reaction, and 5% of the amino groups of the original amino acids that have not reacted. For product 16, a similar ratio is 0.92.

 Products 1A and 1B were tested as collector reagents during flotation of poor apatite ore of the Oshurkovskoye deposit, as well as refractory current waste from the magnetic processing plant of the Kovdorsky mining and processing plant. The material was ground to a particle size of 0.25 mm, de-slurred in a hydrocyclone, treated with soda (1500 g / t) and liquid glass (500 g / t). Flotation was carried out according to the scheme, including the main operation with two cleanings. The chemical composition of ore samples is given in table. 2.

 Data on flotation tests in comparison with N-acylated amino acids based on protein hydrolyzate (product 2) are given in table. 3).

The data table. 3 indicate that the products obtained as collector reagents can improve the quality of apatite concentrate, increase the recovery of P ₂ O ₅ and improve the structural and mechanical properties of the foam both in the enrichment of poor apatite ore of the Oshurkovskoye deposit and refractory wastes of the Kovdorsky GOK MPF. (56) Patent GB N 1460286, cl. C 07 C 101/30, 1976.

 US Pat. No. 4,358,368, cl. B 03 D 1/14, 1982.

 USSR copyright certificate N 1494309, cl. B 03 D 1/016, 1987.

Claims (1)

A METHOD FOR PRODUCING A FLOTATION AGENT, which provides for the modification of amino acids obtained from protein raw materials, characterized in that, in order to improve the flotation properties of the target product, the hydrolyzate of endocrine production wastes or the complex of amino acids used in the production of papoura are used as protein raw materials, higher aliphatic oxiranes C ₉ - C ₁₆ when heated or boiled in a water-alcohol medium for 5 - 6 hours.

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