阅读说明：本技术 一种n-叔丁基酯类捕收剂及其制备方法 (N-tert-butyl ester collecting agent and preparation method thereof ) 是由 李国尧 梁治安 王乾坤 孙忠梅 罗忠岩 廖银英 董浩 于 2021-09-10 设计创作，主要内容包括：本发明公开了一种N-叔丁基酯类捕收剂及其制备方法,利用叔丁基取代基的供电子诱导效应,增加了硫代羰基的电子云密度,增强了其与硫化矿物的捕收能力,实现对多金属硫化矿的高效综合回收。(The invention discloses an N-tert-butyl ester collecting agent and a preparation method thereof, which utilize the electron induction effect of a tert-butyl substituent to increase the electron cloud density of thiocarbonyl, enhance the collecting capability of the thiocarbonyl and sulfide minerals and realize the high-efficiency comprehensive recovery of multi-metal sulfide minerals.)

1. An N-tert-butyl ester collector, which is characterized in that the N-tert-butyl ester collector is N-tert-butyl-O-alkyl thiourethane with a structure shown in a formula I or N-tert-butyl-N-alkyl thiourea with a structure shown in a formula II:

wherein R is₁Is C₄～C₇A hydrocarbon group of R₂Is C₂～C₄A hydrocarbon group of (1).

2. A collector of the N-tert-butyl ester type according to claim 1, wherein R is₁Is any one of n-butyl, isobutyl, n-pentyl, isopentyl and benzyl, R₂Is any one of ethyl, hydroxyethyl, n-propyl and n-butyl.

3. A method for preparing an N-tert-butyl ester collector according to any one of claims 1 to 2, wherein the N-tert-butyl ester collector is an N-tert-butyl-O-alkylsulfuric ester with a structure of formula I, and the specific process of the method is as follows:

1) dissolving thiocyanate with water, adding tert-butyl chloride, and after the reaction is finished under the stirring condition, separating a lower layer of aqueous solution containing chloride by using a separating funnel to obtain tert-butyl thiocyanate;

2) adding a catalyst into the tert-butyl thiocyanate prepared in the step 1) to perform a rearrangement reaction to obtain tert-butyl isothiocyanate;

3) adding alcohol and a catalyst into the tert-butyl isothiocyanate obtained in the step 2), and stirring for reaction to obtain the N-tert-butyl-O-alkylsulfuric ester.

4. The method according to claim 3, wherein in step 1), the mass ratio of the tert-butyl chloride to the thiocyanate is 1: 1.0 to 1.2; the dosage of the solvent water is 10-15 ml/0.1mol of thiocyanate; the reaction temperature is 40 ℃, and the reaction time is 6-12 hours; the thiocyanate is any one of sodium thiocyanate and ammonium thiocyanate.

5. The method according to claim 3, wherein in the step 2), the catalyst is any one of zinc chloride or nickel chloride, and the mass ratio of the tert-butyl thiocyanate to the catalyst is 1: 0.01-0.05; the reaction temperature is 100-110 ℃, and the reaction time is 3 h.

6. The method according to claim 3, wherein in step 3), the catalyst is any one of tetrabutyl titanate or stannous chloride; the mass ratio of the tert-butyl isothiocyanate, the alcohol and the catalyst is 1: 1.0-1.2: 0.01 to 0.05; the reaction temperature is 100-150 ℃, and the reaction time is 4-10 hours.

7. A method for preparing an N-tert-butyl ester collector according to any one of claims 1 to 2, wherein the N-tert-butyl ester collector is N-tert-butyl-N-alkyl thiourea with a structure shown in formula ii, and the specific process of the method is as follows:

(1) dissolving thiocyanate with water, adding tert-butyl chloride, and after the reaction is finished under the stirring condition, separating a lower layer of aqueous solution containing chloride by using a separating funnel to obtain tert-butyl thiocyanate;

(2) adding a catalyst into the tert-butyl thiocyanate prepared in the step (1) to carry out rearrangement reaction to obtain tert-butyl isothiocyanate;

(3) and (3) adding toluene into the tert-butyl isothiocyanate obtained in the step (2), slowly adding amine, stirring for reaction, and distilling to remove the solvent after the reaction is finished to obtain the N-tert-butyl-N-alkyl thiourea.

8. The method according to claim 7, wherein in the step (1), the mass ratio of the tert-butyl chloride to the thiocyanate is 1: 1.0 to 1.2; the dosage of the solvent water is 10-15 ml/0.1mol of thiocyanate; the reaction temperature is 40 ℃, and the reaction time is 6-12 hours; the thiocyanate is any one of sodium thiocyanate and ammonium thiocyanate.

9. The method according to claim 7, wherein in the step (2), the catalyst is any one of zinc chloride or nickel chloride, and the mass ratio of the tert-butyl thiocyanate to the catalyst is 1: 0.01-0.05; the reaction temperature is 100-110 ℃, and the reaction time is 3 h.

10. The method according to claim 7, wherein in the step (3), the amount ratio of the tert-butyl isothiocyanate to the amine is 1: 1.0-1.2; the dosage of the solvent toluene is 10-20 ml/0.1mol of tert-butyl isothiocyanate; the reaction temperature is 30-100 ℃, and the reaction time is 4-8 hours.

Technical Field

The invention relates to the technical field of mineral processing, and particularly relates to an N-tert-butyl ester collecting agent and a preparation method thereof.

Background

The flotation method is the most important method for enriching useful minerals, and is a method for sorting minerals by utilizing the difference of physicochemical properties of the surfaces of the minerals (particularly, the difference of surface wettability, and the difference of wettability between the minerals is enlarged by a method of adding a specific flotation reagent). The flotation collector is one of key technologies for separating and extracting valuable mineral components by a flotation method, and is directly related to the quality of a flotation effect.

The thiourethane and thiourea compounds have good chelation effect on metal ions such as copper, gold, silver and the like, and become important sulfide ore collecting agents. Chinese patent CN101890397A discloses a collecting agent prepared by mixing isopropyl ethyl thiourethane and kerosene according to a certain proportion, which can realize effective recovery of arsenic-containing copper minerals. In order to further improve the flotation performance of the thiourethane, a plurality of thiourethane collectors with novel structures are developed successively. Chinese patent CN1153774A discloses a preparation method of allyl thiourethane. Chinese patent CN1548418A discloses a preparation method of N-hydrocarbonoxy carbonyl thiourethane. Chinese patent CN103041929A discloses preparation and application of a double-ligand collector, which can reduce the melting point of the collector and enhance the dispersibility of the collector in aqueous solution. Chinese patent CN112676045A discloses a hydroxyl thiourethane compound and a preparation method and application thereof, wherein the hydroxyl thiourethane compound and derivatives thereof have good dispersion effect in the flotation process, and can act with a mineral together with a thiourethane group to realize intramolecular synergy. With the poor, fine and hybrid development of domestic mineral resources, a novel efficient flotation collector is developed, and the novel efficient flotation collector plays an important role and value in improving the flotation efficiency and the metal recovery rate of valuable minerals.

Disclosure of Invention

The invention aims to provide an N-tert-butyl ester collecting agent and a preparation method thereof, which utilize the electron induction effect of a tert-butyl substituent to increase the electron cloud density of thiocarbonyl, enhance the collecting capability of the thiocarbonyl and sulfide minerals and realize the efficient and comprehensive recovery of multi-metal sulfide minerals.

In order to achieve the purpose, the invention adopts the following technical scheme:

an N-tert-butyl ester collector which is an N-tert-butyl-O-alkylsulfourethane having the structure of formula I or an N-tert-butyl-N-alkylthiourea having the structure of formula II:

wherein R is₁Is C₄～C₇A hydrocarbon group of R₂Is C₂～C₄A hydrocarbon group of (1).

Further, R₁Is any one of n-butyl, isobutyl, n-pentyl, isopentyl and benzyl, R₂Is any one of ethyl, hydroxyethyl, n-propyl and n-butyl.

The invention also provides a preparation method of the N-tert-butyl ester collecting agent, wherein the N-tert-butyl ester collecting agent is N-tert-butyl-O-alkyl thiourethane with a structure shown in the formula I, and the preparation method comprises the following specific processes:

1) dissolving thiocyanate with water, adding tert-butyl chloride, and after the reaction is finished under the stirring condition, separating a lower layer of aqueous solution containing chloride by using a separating funnel to obtain tert-butyl thiocyanate;

2) adding a catalyst into the tert-butyl thiocyanate prepared in the step 1) to perform a rearrangement reaction to obtain tert-butyl isothiocyanate;

3) adding alcohol and a catalyst into the tert-butyl isothiocyanate obtained in the step 2), and stirring for reaction to obtain the N-tert-butyl-O-alkylsulfuric ester.

Further, in the step 1), the mass ratio of the tert-butyl chloride to the thiocyanate is 1: 1.0-1.2; the dosage of the solvent water is 10-15 ml/0.1mol of thiocyanate; the reaction temperature is 40 ℃, and the reaction time is 6-12 hours; the thiocyanate is any one of sodium thiocyanate and ammonium thiocyanate.

Further, in the step 2), the catalyst is any one of zinc chloride or nickel chloride, and the mass ratio of the tert-butyl thiocyanate to the catalyst is 1: 0.01-0.05; the reaction temperature is 100-110 ℃, and the reaction time is 3 h.

Further, in the step 3), the catalyst is any one of tetrabutyl titanate or stannous chloride; the mass ratio of the tert-butyl isothiocyanate, the alcohol and the catalyst is 1: 1.0-1.2: 0.01 to 0.05; the reaction temperature is 100-150 ℃, and the reaction time is 4-10 hours.

The invention also provides another preparation method of the N-tert-butyl ester collecting agent, wherein the N-tert-butyl ester collecting agent is N-tert-butyl-N-alkyl thiourea with a structure shown in a formula II, and the preparation method comprises the following specific processes:

(1) dissolving thiocyanate with water, adding tert-butyl chloride, and after the reaction is finished under the stirring condition, separating a lower layer of aqueous solution containing chloride by using a separating funnel to obtain tert-butyl thiocyanate;

(2) adding a catalyst into the tert-butyl thiocyanate prepared in the step (1) to carry out rearrangement reaction to obtain tert-butyl isothiocyanate;

(3) and (3) adding toluene into the tert-butyl isothiocyanate obtained in the step (2), slowly adding amine, stirring for reaction, and distilling to remove the solvent after the reaction is finished to obtain the N-tert-butyl-N-alkyl thiourea.

Further, in the step (1), the mass ratio of the tert-butyl chloride to the thiocyanate is 1: 1.0-1.2; the dosage of the solvent water is 10-15 ml/0.1mol of thiocyanate; the reaction temperature is 40 ℃, and the reaction time is 6-12 hours; the thiocyanate is any one of sodium thiocyanate and ammonium thiocyanate.

Further, in the step (2), the catalyst is any one of zinc chloride or nickel chloride, and the mass ratio of the tert-butyl thiocyanate to the catalyst is 1: 0.01-0.05; the reaction temperature is 100-110 ℃, and the reaction time is 3 h.

Further, in the step (3), the mass ratio of the tert-butyl isothiocyanate to the amine is 1: 1.0-1.2; the dosage of the solvent toluene is 10-20 ml/0.1mol of tert-butyl isothiocyanate; the reaction temperature is 30-100 ℃, and the reaction time is 4-8 hours.

The invention has the beneficial effects that:

(1) the tert-butyl substituent group of the N-tert-butyl ester collecting agent provided by the invention has a strong electron induction effect, the electron cloud density of thiocarbonyl is increased, the collecting capability of the thiocarbonyl and sulfide minerals is enhanced, and the comprehensive recovery rate of gold, copper and lead of multi-metal sulfide minerals is improved.

(2) The preparation method of the N-tert-butyl ester collecting agent provided by the invention is simple, efficient, environment-friendly and easy to realize industrialization.

(3) The N-tert-butyl ester collecting agent provided by the invention has no pungent smell, the using amount of the agent is small, and the used raw materials have the characteristics of wide sources and high yield, and can be applied to the flotation of polymetallic sulfide ores.

Drawings

FIG. 1 is an infrared spectrum of N-tert-butyl-O-N-butylthionocarbamate prepared in example 1 of the present invention.

FIG. 2 is an infrared spectrum of N-tert-butyl-O-N-pentylthionocarbamate prepared in example 6 of the present invention.

FIG. 3 is an infrared spectrum of N-tert-butyl-O-benzylthiourethane prepared in example 7 of the present invention.

FIG. 4 is an IR spectrum of N-tert-butyl-N-hydroxyethylthiourea prepared in example 8 of the present invention.

Detailed Description

The present invention will be further described with reference to the accompanying drawings, and it should be noted that the present embodiment is based on the technical solution, and the detailed implementation and the specific operation process are provided, but the protection scope of the present invention is not limited to the present embodiment.

Example 1

The embodiment provides an N-tert-butyl ester collecting agent, which is N-tert-butyl-0-N-butyl thiourethane, and the preparation method thereof is as follows:

s1, adding 0.30mol of ammonium thiocyanate into a reactor, adding 30mL of solvent water, stirring for dissolving, then adding 0.30mol of tert-butyl chloride, reacting for 12 hours at 40 ℃ under stirring, and separating the lower layer of chloride salt-containing aqueous solution by using a separating funnel to obtain tert-butyl thiocyanate, wherein the purity of the obtained tert-butyl thiocyanate reaches 96.62%, and the yield is 94.54%.

The specific synthesis reaction is shown as the following formula:

MSCN+(CH₃)₃CCl→(CH₃)₃CSCN+MCl

s2, adding the synthesized tert-butyl thiocyanate (0.20mol) into a 100mL reaction bottle, then adding 0.004mol of anhydrous zinc chloride into the reaction bottle, and carrying out rearrangement reaction for 3h under the condition of stirring at 110 ℃ to obtain tert-butyl isothiocyanate, wherein the purity of the obtained tert-butyl isothiocyanate reaches 98.82%, and the yield is 94.68%.

The specific synthesis reaction is shown as the following formula:

(CH₃)₃C-S-C≡N→(CH₃)₃C-N＝C＝S

s3, adding the synthesized tert-butyl isothiocyanate (0.15mol) into a 100mL reaction bottle, adding 0.18mol of N-butyl alcohol and 0.0075mol of tetrabutyl titanate catalyst into the reaction bottle, and reacting for 6h at 115 ℃ under stirring to obtain N-tert-butyl-0-N-butyl thiourethane, wherein the purity of the obtained N-tert-butyl-0-N-butyl thiourethane is 82.54%, and the yield is 80.60%.

The specific synthesis reaction is shown as the following formula:

the infrared spectrogram of the prepared N-tertiary butyl-O-N-butyl thionocarbamate is shown in figure 1.

Example 2

This example is essentially the same as example 1, with the main difference that, by adding 0.15mol of N-butanol in step S3, N-tert-butyl-O-N-butylthiourethane is obtained with a purity of 81.02% and a yield of 78.85%.

Example 3

This example is essentially the same as example 1, with the main difference that in step S3, the reaction time was 10 hours, and the purity of the obtained N-tert-butyl-O-N-butylthionocarbamate reached 84.08% with a yield of 81.45%.

Example 4

This example is essentially the same as example 1, with the main difference that in step S3, the reaction time was 4 hours, and the purity of the obtained N-tert-butyl-O-N-butylthionocarbamate reached 79.52% with a yield of 76.16%.

Example 5

This example provides an N-tert-butyl-O-N-butylthionocarbamate, which is prepared by the following steps:

s1, adding 0.30mol of sodium thiocyanate into a reactor, adding 45mL of solvent water, stirring for dissolving, then adding 0.30mol of tert-butyl chloride, reacting for 6 hours at 40 ℃ under stirring, and separating the lower layer of aqueous solution containing chloride salt by using a separating funnel to obtain tert-butyl thiocyanate, wherein the purity of the obtained tert-butyl thiocyanate reaches 92.36%, and the yield is 90.14%.

S2, adding the synthesized tert-butyl thiocyanate (0.20mol) into a 100mL reaction bottle, then adding 0.004mol of anhydrous nickel chloride into the reaction bottle, and carrying out rearrangement reaction for 3h under the condition of stirring at 110 ℃ to obtain tert-butyl isothiocyanate, wherein the purity of the obtained tert-butyl isothiocyanate reaches 90.12%, and the yield is 88.48%.

S3, adding the synthesized tert-butyl isothiocyanate (0.15mol) into a 100mL reaction bottle, adding 0.18mol of N-butyl alcohol and 0.0075mol of tetrabutyl titanate catalyst into the reaction bottle, and reacting for 6h under the condition of stirring at 100 ℃ to obtain N-tert-butyl-O-N-butyl thiourethane, wherein the purity of the obtained N-tert-butyl-O-N-butyl thiourethane reaches 78.45%, and the yield is 72.36%.

Example 6

This example provides an N-tert-butyl ester collector, which is N-tert-butyl-O-N-pentylthionocarbamate, and the preparation process is as follows:

s1, adding 0.36mol of sodium thiocyanate into a reactor, adding 36mL of solvent water, stirring for dissolving, then adding 0.30mol of tert-butyl chloride, reacting for 12 hours at 40 ℃ under stirring, and separating the lower layer of aqueous solution containing chloride salt by using a separating funnel to obtain tert-butyl thiocyanate, wherein the purity of the obtained tert-butyl thiocyanate reaches 96.84% and the yield is 95.64%.

S2, adding the synthesized tert-butyl thiocyanate (0.20mol) into a 100mL reaction bottle, then adding 0.002mol of anhydrous zinc chloride into the reaction bottle, and carrying out rearrangement reaction for 3h under the condition of stirring at 110 ℃ to obtain tert-butyl isothiocyanate, wherein the purity of the obtained tert-butyl isothiocyanate reaches 96.82%, and the yield is 92.46%.

S3, adding the synthesized tert-butyl isothiocyanate (0.15mol) into a 100mL reaction bottle, adding 0.18mol of N-amyl alcohol and 0.0075mol of tetrabutyl titanate catalyst into the reaction bottle, and reacting for 6h at 135 ℃ under stirring to obtain N-tert-butyl-O-N-pentylthiourethane, wherein the purity of the obtained N-tert-butyl-O-N-pentylthiourethane is 86.64%, and the yield is 83.50%.

The infrared spectrogram of the prepared N-tertiary butyl-O-N-pentylthionocarbamate is shown in figure 2.

Example 7

The embodiment provides an N-tert-butyl ester collecting agent, which is N-tert-butyl-O-benzylthiourethane, and the preparation method thereof is as follows:

s1, adding 0.30mol of ammonium thiocyanate into a reactor, adding 45mL of solvent water, stirring for dissolving, then adding 0.30mol of tert-butyl chloride, reacting for 12 hours at 40 ℃ under stirring, and separating the lower layer of chloride salt-containing aqueous solution by using a separating funnel to obtain tert-butyl thiocyanate, wherein the purity of the obtained tert-butyl thiocyanate reaches 95.56% and the yield is 92.74%.

S2, adding the synthesized tert-butyl thiocyanate (0.20mol) into a 100mL reaction bottle, then adding 0.01mol of anhydrous zinc chloride into the reaction bottle, and carrying out rearrangement reaction for 3h under the condition of stirring at 110 ℃ to obtain tert-butyl isothiocyanate, wherein the purity of the obtained tert-butyl isothiocyanate reaches 99.23%, and the yield is 95.88%.

S3, adding the synthesized tert-butyl isothiocyanate (0.15mol) into a 100mL reaction bottle, adding 0.15mol of benzyl alcohol and 0.0015mol of tetrabutyl titanate catalyst into the reaction bottle, and reacting for 6h at 150 ℃ under stirring to obtain N-tert-butyl-O-benzylthiourethane, wherein the purity of the obtained N-tert-butyl-O-benzylthiourethane reaches 81.74%, and the yield is 78.62%.

The infrared spectrogram of the prepared N-tertiary butyl-O-benzylthiourethane is shown in figure 3.

Example 8

This example provides an N-tert-butyl ester collector, which is N-tert-butyl-N-hydroxyethyl thiourea, and the preparation process is as follows:

s1, adding 0.30mol of ammonium thiocyanate into a reactor, adding 30mL of solvent water, stirring for dissolving, then adding 0.30mol of tert-butyl chloride, reacting for 8 hours at 40 ℃ under stirring, and separating the lower layer of chloride salt-containing aqueous solution by using a separating funnel to obtain tert-butyl thiocyanate, wherein the purity of the obtained tert-butyl thiocyanate reaches 93.45% and the yield is 91.70%.

S2, adding the synthesized tert-butyl thiocyanate (0.20mol) into a 100mL reaction bottle, then adding 0.004mol of anhydrous zinc chloride into the reaction bottle, and carrying out rearrangement reaction for 3h under the condition of stirring at 100 ℃ to obtain tert-butyl isothiocyanate, wherein the purity of the obtained tert-butyl isothiocyanate reaches 96.43%, and the yield is 92.28%.

S3, respectively adding 0.15mol of tert-butyl isothiocyanate and 30mL of toluene into a 150mL reaction bottle, then slowly adding 0.15mol of monoethanolamine under stirring, stirring and reacting for 4h at 80 ℃, and distilling to remove the solvent after the reaction is finished to obtain the N-tert-butyl-N-hydroxyethyl thiourea, wherein the purity of the obtained N-tert-butyl-N-hydroxyethyl thiourea reaches 94.65%, and the yield is 92.80%.

The specific synthesis reaction is shown as the following formula:

the infrared spectrum of the prepared N-tertiary butyl-N-hydroxyethyl thiourea is shown in figure 3.

Example 9

This example is substantially the same as example 8, except that 15mL of toluene and 0.18mol of monoethanolamine were added in step S3, and the reaction was stirred at 100 ℃ for 8 hours to obtain N-tert-butyl-N-hydroxyethylthiourea having a purity of 89.43% and a yield of 87.68%.

Example 10

This example is substantially the same as example 8, except that the reaction temperature in step S3 was 30 ℃ and N-t-butyl-N-hydroxyethylthiourea was obtained in 91.24% purity and 90.36% yield.

The infrared analyses of the products of examples 1 to 10 are shown in Table 1.

TABLE 1 Infrared resolution of target products

Example 11

The main metal minerals in a certain gold-containing copper sulfide ore are chalcopyrite, pyrite and tetrahedrite. The gold, copper and sulfur grades of the raw ore are respectively as follows: au 0.56g/t, Cu 0.85%, S2.02%. The test process is a primary roughing; flotation conditions are as follows: grinding fineness: 76.1% of-0.074 mm, 500g/t of lime, 30g/t of collecting agent and 15g/t of 2# oil. The results are shown in Table 2, and the test conditions were the same except for the type of collector in the comparative examples. The test results in table 2 show that higher copper and gold flotation recovery rates were achieved for the flotation of the gold-bearing copper sulfide ores using the N-tert-butyl-O-N-butylthionocarbamate described in examples 1-5 and the N-tert-butyl-O-N-pentylthionocarbamate described in example 6, as compared to the commonly used butyl xanthate and Z-200 collectors.

TABLE 2 flotation results for certain gold-containing sulphidic ores

Example 12

The main metal minerals in the copper-lead sulfide ore are chalcopyrite, pyrite and galena. The copper, lead and sulfur grades of the raw ore are respectively as follows: cu 0.74%, Pb 2.17%, S2.86%. The test process is a primary roughing; flotation conditions are as follows: grinding fineness: 75.0% of-0.074 mm, 800g/t of lime, 30g/t of collecting agent and 20g/t of 2# oil. The results are shown in Table 3, and the test conditions were the same except for the type of collector in the comparative examples. The test results in table 3 show that compared with the commonly used ester collector Z-200, the N-tert-butyl-O-N-butylthionocarbamate collecting agent described in examples 1-5 and the N-tert-butyl-O-N-pentylthionocarbamate collecting agent described in example 6 are used for flotation of the gold-containing copper sulfide ore to achieve higher copper and lead flotation recovery rates.

TABLE 3 flotation results for certain copper-lead sulfide ores

Example 13

The main metal minerals in a certain copper sulfide ore are chalcocite, pyrite and tetrahedrite. The copper and sulfur grades of the raw ore are respectively as follows: cu 0.55% and S3.52%. The test process is a primary roughing; flotation conditions are as follows: grinding fineness: 70.0% of-0.074 mm, 500g/t of lime, 20g/t of N-tert-butyl-N-hydroxyethyl thiourea described in examples 8-10, 10g/t of butyl xanthate and 20g/t of No. 2 oil. The yield of the copper rough concentrate obtained by the primary roughing is 6.21%, the copper-containing grade is 7.39%, and the copper recovery rate is 83.44%.

Various corresponding changes and modifications can be made by those skilled in the art based on the above technical solutions and concepts, and all such changes and modifications should be included in the protection scope of the present invention.