RU2448174C1 - Para-tertbutylbenzoic acid "n', n'-dialkylhydrazides - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: invention relates to novel compounds of the N',N'-dialkylhydrazide class and can be used in copper hydrometallurgy. Para-tertbutylbenzoic acid N',N'-dialkylhydrazides of general formula tertC₄H₉C₆H₄CONHN(R)₂ are obtained, where R is an aliphatic radical C_nH_2n+1 n=1-10. The compounds, preferably with number of carbon atoms per radical (n) from 6 to 10, are used as an extraction agent for copper (II) from ammonia solutions. Degree of extraction of copper (II) from solutions with ammonia content of up to 8 mol/l is equal to 96.5-99.4%.

EFFECT: compounds have high solubility in aliphatic hydrocarbon solvents.

2 cl, 3 tbl, 5 ex

Description

The invention relates to new compounds of the class N ', N'-dialkylhydrazides and can be used in the field of copper hydrometallurgy, in particular, as an extraction reagent for the extraction of copper (II) from ammonia media.

Descriptions of the claimed compounds, their properties and applications in the information sources were not found.

Known use as an extraction reagent for the extraction of copper (II) from ammonia solutions of β-hydroxyoximes [Flett DS, Melling J. Extraction of ammonia by commercial copper chelating extractants // Hydrometallurgy - 1979 - V.4 - No. 2 - P.135- 146]. The disadvantage of 3-hydroxy oximes is the transfer of ammonia with the organic phase, which requires the introduction of an additional washing step to remove it.

The use of β-diketones in this capacity is also known [Alguacil FJ, Alonso M. Recovery of copper from ammoniacal / ammonium sulfate medium by LIX 54 // Journal of Chemical Technology and Biotechnology - 1999 - V.74 - P.1171-1175.] . β-Diketones do not tolerate ammonia, but their disadvantage is the decrease in the efficiency of copper (II) extraction with an increase in the content of ammonia and ammonium salts. For example, at pH> 8.5 and a content of ammonium sulfate 0.15 mol / L, the degree of extraction of copper (II) with β-diketone with the commercial name LIX 54 sharply decreases.

The closest analogue in technical essence and the achieved result to the claimed compounds are N ', N'-dialkylhydrazides of benzoic acid (DAHBK) of the general formula C ₆ H ₅ CONHN (R) ₂ , where R is the aliphatic radical C _n H _{2n + 1} [Gusev V.Yu., Baigacheva E.V., Radushev A.V. Complexation of copper (II) with 1,1-diethyl-2-benzoylhydrazine // Journal of Inorganic Chemistry - 2007 - V.52 - No. 7 - S.1089-1093; Radushev A.V., Gusev V.Yu., Batueva T.D., Bogomazova G.S., Shabalina L.S., Tyryshkina V.N., Karmanov V.I. Extraction and complexation of copper (II) with N, N-dihexylbenzhydrazide // Journal of Inorganic Chemistry - 2006 - T.51 - No. 12 - S.2096-2099]. These compounds do not tolerate ammonia. Their solutions in xylene recover copper (II) by 98-99% to an ammonia concentration of 1-1.5 mol / L.

The disadvantage of these compounds is that with an increase in the ammonia concentration of more than 1.5 mol / L, the degree of extraction of copper (II) decreases and with its content of ~ 4 mol / L is 40-75%. In addition, they are poorly soluble in the most widely used in industrial extraction processes aliphatic hydrocarbon solvents, which limits the possibility of their use.

The objective of the invention is to obtain extraction reagents capable of extracting copper (II) from solutions with an ammonia content of more than 1.5 mol / l and well compatible with aliphatic hydrocarbon solvents.

To solve the problem synthesized:

1. N ', N'-Dialkylhydrazides of para-tert-butylbenzoic acid of the general formula (I):

where R is the aliphatic radical C _n H _{2n + 1} , n = 1-10.

2. N ', N'-Dialkylhydrazides according to claim 1, mainly with the number of carbon atoms in radical (n) from 6 to 10 as an extraction reagent for the extraction of copper (II) from ammonia solutions.

Synthesized compounds of General formula (I), where R is CH ₃ (1); C ₄ H ₉ (2); C ₆ H ₁₃ (3); C ₈ H ₁₇ (4) and C ₁₀ H ₂₁ (5).

The compounds of general formula (I) are white crystalline substances, insoluble in water. They are well soluble in alcohol, chloroform, aromatic hydrocarbon solvents. Compounds with a radical length of C ₆ H ₁₃ and higher dissolve well in aliphatic hydrocarbon solvents.

The synthesis of compounds of General formula (I)

Example 1. The synthesis of compounds (3), (4) and (5)

19.2 g (0.1 mol) of para-tert-butylbenzoic acid hydrazide was dissolved in 100 ml of isopropyl alcohol (i-PrOH), 34.8 ml (0.2 mol) of octyl bromide was added and a solution of 11.2 g (dropwise) was added dropwise with stirring. 0.2 mol) potassium hydroxide in 100 ml of i-PrOH. After adding all the hydroxide, the reaction mixture was heated until neutral. I-PrOH was distilled off, ~ 50 ml of hexane was added to the residue. Hexane was filtered and distilled off. The residue was a thick, difficult to crystallize resin. It was dissolved in i-PrOH, water was added until the turbidity was released, rubbed with a glass rod on the walls of the vessel and placed in a freezer. If the separated product remained liquid, then i-PrOH was added until it was dissolved, then water until turbidity appeared and again placed in the freezer. The resulting crystals were recrystallized from i-PrOH: water = 2.5: 1.

Compound (3): yield 17%. T _pl. = 55.5-56 ° C (i-PrOH: water = 1.5: 1). Rr = 0.72 (m-xylene-butanol = 2: 1). Found,%: C 76.62, 76.62; H 11.44, 11.16; N, 7.75, 7.74. C ₂₃ H ₄₀ N ₂₀ . Calculated,%: C 76.61; H 11.18; N, 7.77.

Compound (4): yield 27%. T _pl. = 44-45 ° C. R _f = 0.74 (m-xylene-butanol = 2: 1). Found,%: C 78.24; H 11.62; N, 6.66. C ₂₇ H ₄₈ N ₂₀ . Calculated,%: C 77.83; H, 11.61; N, 6.72.

Compound (5): yield 19%. T _pl. = 59.5 ° C (i-PrOH: water = 4: 1). R _f = 0.74 (m-xylene-butanol = 2: 1). Found,%: C 78.68, 78.57; H, 11.84; 11.85; N, 5.87; 5.84. C ₃₁ H ₅₆ N ₂ O. Calculated,%: C 78.75; H 11.94; N, 5.92.

Example 2. Synthesis of compound (2)

Received similarly to the procedure described in example 1. Instead of hexane, the resulting product was dissolved in chloroform, filtered, chloroform was distilled off and then acted as described in example 1.

The yield is 22%. T _pl. = 94.5-95 ° C (i-PrOH: water = 1.5: 1). Rf- = 0.76 (m-xylene-butanol = 2: 1). Found,%: C 75.10; H 10.65; N, 9.27. C ₉ H ₃₂ N ₂ O. Calculated,%: C 74.95; H 10.59; N, 9.20.

Example 3. Synthesis of compound (1)

45.5 ml (0.6 mol) of 1,1-dimethylhydrazine was dissolved in 250 ml of hexane and cooled with a mixture of snow and salt. Upon cooling, a cooled solution of 58 ml (0.29 mol) of para-tert-butylbenzoic acid chloride in 100 ml of hexane was added dropwise to the resulting solution. After completion of the dropping, the reaction mixture stood overnight. The next day, the precipitate formed was filtered off. It was dissolved in 200 ml of chloroform and the insoluble part was filtered off. After distillation of chloroform, the residue was recrystallized from a mixture of water - i-PrOH = 3: 1.

The yield is 57%. _Mp = 143-144 ° C. Found,%: C 70.82, 70.76; H, 9.03; 9.07; N, 12.70; 12.69. C ₁₃ H ₂₀ N ₂ O. Calculated,%: C 70.87; H, 9.15; N, 12.72.

The structure of compounds of general formula (I) was confirmed by elemental analysis data performed on a CHNS-932 analyzer (LECO Corporation, USA), IR spectra (recorded on an IFS 66 / S Bruker Fourier spectrometer in liquid paraffin), ¹ H NMR spectra (obtained on the spectrometer "MERCURY plus 300" in CDCl ₃ ).

The spectral characteristics of the claimed compounds are presented in table 1.

The obtained compounds of general formula (I) were investigated as extraction reagents for the extraction of copper (II) from ammonia solutions. During the extraction process, they do not tolerate ammonia with the organic phase due to very weak acidic properties and are able to extract copper (II) from solutions with an NH ₃ content of 2 to 9 mol / L with a recovery of ≥93% (Table 2).

Compounds with R <C ₆ H _{13 are} slightly or practically insoluble in industrial aliphatic hydrocarbon solvents, for example kerosene (table 3). Therefore, the extraction properties of compounds with the number of carbon atoms in the radical (n) from 6 to 10, which are readily soluble in these solvents and, as a result, can be used in copper hydrometallurgy as extraction reagents for its extraction from ammonia solutions with ammonia content up to 8-9.5 mol / l with a degree of extraction of 96.5-99.4%.

The study of the extraction properties of the compounds of General formula (I)

Example 4

5 ml of a 0.016 mol / L CuSO ₄ solution, an ammonia solution to create the necessary medium were placed in a separatory funnel and adjusted to 25 ml with water. After that, 5 ml of 0.05 mol / L of compound was added. The funnel was shaken for 3 minutes and kept until phase separation was complete. The aqueous layer was separated, the pH was measured and the residual copper (II) content was determined by the photometric method with sodium diethyldithiocarbamate.

The results are presented in table 2.

The table shows that in comparison with the prototype, all of the claimed compounds provide a high degree of extraction of copper (II) from solutions with a higher ammonia content. The best extraction properties are possessed by compounds (3), (4), (5), which effectively extract it with an ammonia content of 8–9.5 mol / L.

The solubility of the compounds of General formula (I)

Example 5. Determination of the solubility of compounds (1) and (2)

5 ml of a solution of the compound in hexane saturated at (20 ± 0.5) ° C for 6 hours was evaporated in an oven in a weighing bottle, brought to constant weight, at a temperature of 10-15 ° C above the boiling point of hexane. The bucks with the substance were brought to constant weight and solubility was calculated.

Example 6. Determination of the solubility of compounds (3), (4) and (5)

A fixed volume of solvent was added to a sample of the compound taken with an accuracy of 0.0001 g and placed in the bottle until the substance was completely dissolved. After that, solubility was calculated.

The results of studies of the solubility of the compounds of general formula (I) in hexane and kerosene are presented in table 3.

The table shows that, in comparison with the prototype, the compounds of general formula (I) with n = 6-10 are much better soluble in aliphatic hydrocarbon solvents.

Compounds of General formula (I) have the following advantages compared with the prototype:

- able to extract copper (II) from solutions with an ammonia content of ≥2 mol / l;

- compounds with a radical length of C ₆ H ₁₃ and higher dissolve well in industrial aliphatic hydrocarbon solvents (kerosene) and can be used as extraction reagents for the extraction of copper (II) from ammonia solutions with an ammonia content of up to 8-9.5 mol / l with a degree of extraction of 96.5-99.4%.

Table 1 The spectral characteristics of the compounds of General formula (I) Connection No. IR spectra, ν / cm ^-1 NMR ¹ N, δ / ppm, J / Hz N-h Amide I Amid II one 3209 1644 1550 1.38 (s, 9 N, tC ₄ H ₉ ); 2.68 (s, 6H, 2 NCH ₃ ); 7.04, 7.10 (s, 1 H, NH, Z and E isomers); 7.40 (d, 2 N, C ₆ H ₄ , 8.4); 7.67 (d, 2H, C ₆ H ₄ , 8.1). 2 3290 1654 1546 0.88 (t, 6 N, 2 CH ₃ , 7.4); 1.31; 1.29-1.40 (s, m, 13 N, tC ₄ H ₉ and 2 CH ₃ C H ₂ respectively); 1.54 (m, 4 H, 2 NCH ₂ C H ₂ ); 2.81 (t, 4 H, 2 NCH ₂ , 7.5); 6.57 (br s, 1 H, NH); 7.43 (d, 2 N, C ₆ H ₄ , 8.4); 7.67 (d, 2 N, C ₆ H ₄ , 8.4) 3 3247 1649 1546 0.85 (t, 6 N, 2 CH ₃ , 6.9); 1.28; 1.32 (m, s, 21 N, 2 CH ₃ (C H ₂ ) ₃ and t-C ₄ H ₉ respectively); 1.55 (m, 4 H, 2 NCH ₂ C H ₂ ); 2.81 (t, 4 H, 2 NCH ₂ , 7.6); 6.64 s, 1 H, NH); 7.42 (d, 2 N, C ₆ H ₄ , 8.4); 7.67 (d, 2 N, C ₆ H ₄ , 8.4) four 3209 1644 1550 1.38 (s, 9 N, tC ₄ H ₉ ); 2.68 (s, 6H, 2 NCH ₃ ); 7.04, 7.10 (s, 1 H, NH, Z and E isomers); 7.40 (d, 2 N, C ₆ H ₄ , 8.4); 7.67 (d, 2 N, C ₆ H ₄ , 8.1). 5 3244 1656 1534 0.86 (t, 6 N, 2 CH ₃ , 6.9); 1.23; 1.32 (broad s, s, 37 N, 2 CH ₃ (C H ₂ ) 7 and tC ₄ H ₉ respectively); 1.55 (m, 4 H, 2 NCH ₂ C H ₂ ); 2.80 (t, 4H, 2 NCH ₂ , 8.0); 6.55 (s, 1H, NH); 7.43 (d, 2 N, C ₆ H ₄ , 8.4); 7.67 (d, 2 N, C ₆ H ₄ , 8.4) ν is the wave number, δ is the chemical shift, J is the constant of spin-spin interaction, s is the singlet, d is the doublet, t is the triplet, m is the multiplet, ush. - broadened.

table 2 Extraction of copper (II) from ammonia solutions by compounds of the general formula (I) Connection No. Solvent The degree of extraction,% The maximum concentration of ammonia, mol / l (one) i-AmOH 93 2 (2) o-xylene 97 3 (3) Hexane ≥96.5 8 (3) Kerosene 99,4 8 (3) Kerosene 97.2 9.5 (four) Hexane 96.6 8 (four) Kerosene 98.8 8 (four) Kerosene 93.3 9.5 (5) Hexane ≥96.5 8 (5) Kerosene 99.5 5 (5) Kerosene 96.6 8

Table 3 The solubility of the compounds of General formula (I) and DAHBK, g / l Connection No. (one) (2) (3) (four) (5) DAGBK (prototype) hexane 0.18 fifteen ~ 930 > 1000 > 450 1-2 kerosene - - 1020 1380 ~ 590 -

Claims (1)

1. N ', N'-Dialkylhydrazides of para-tert-butylbenzoic acid of the general formula

,
where R is the aliphatic radical C _n H _{2n + 1} , n = 1-10.
2. N ', N'-dialkyl hydrazides according to claim 1, in which the number of carbon atoms (n) in the aliphatic radical C _n H _{2n + 1} is preferably from 6 to 10, is used as an extraction reagent for the extraction of copper (II) from ammonia solutions.