CN115283144A - W/O type emulsion collector for electrolytic aluminum and preparation and application thereof - Google Patents

Abstract

The invention belongs to the field of carbon residue resource utilization, and relates to a W/O type emulsion collector for electrolytic aluminum and its preparation and application. The present invention adopts kerosene as the outer phase, KCl solution as the inner phase, and alkyl glycoside (or polyisobutylene ethanolamine) as the emulsifier to prepare a high inner phase W/O type emulsion collector, which is used for electrolysis of aluminum carbon In the process of flotation, decarburization and upgrading of slag, it can achieve efficient removal of carbon resources in carbon slag and reduce the content of carbon impurities in co-solvent under the condition of low oil consumption, and the co-solvent can be recycled for electrolytic aluminum. In the process, it is of great significance to the sustainable development of the electrolytic aluminum industry and the resource utilization of carbon slag, and has a good application prospect.

Description

A W/O emulsion collector for electrolytic aluminum and its preparation and application

technical field

The invention belongs to the field of resource utilization of carbon slag, and in particular relates to a W/O emulsion collector for electrolytic aluminum and its preparation and application.

Background technique

my country has become the world's largest aluminum consumer, and the electrolytic aluminum industry has also developed rapidly, with a production capacity of nearly 40 million tons per year. In the process of electrolytic aluminum, both the cathode and the anode are carbon-containing materials, and the carbon materials of the cathode and anode are consumed, peeled off, broken, etc. due to electrochemical reactions and electrolyte immersion, and a large amount of carbon slag will be generated. The carbon residue is mixed with the necessary co-solvent for electrolysis, resulting in a decrease in the efficiency of the co-solvent, which eventually appears as carbon-containing solid waste. At the same time, the solid waste will also be mixed with salt in the electrolyte, so it can only be dumped as hazardous waste, resulting in waste of resources and increased treatment costs.

The important step to realize the resource utilization of electrolytic aluminum carbon-containing solid waste is to separate the carbon from the co-solvent, and the main means of separation is the flotation method. In flotation decarbonization, diesel oil is commonly used as collector and No. 2 oil is used as foaming agent, but the flotation efficiency is poor. Patent CN112844852A discloses a mixed collector made of hydrocarbon oil, lipid oil, phthalate, etc. for the decarbonization of carbon-containing solid waste in electrolytic aluminum. Although the flotation effect has been improved, the oil consumption is large. Moreover, the treatment effect on fine-grained carbon-containing solid waste is poor, and the carbon impurity content of the obtained co-solvent is still high, making it difficult to continue recycling.

Contents of the invention

The purpose of the present invention is to provide a W/O type emulsion collector for electrolytic aluminum and its preparation and application, focusing on the resource utilization of high-carbon waste residue, to solve the problem of large oil consumption and flotation in the existing flotation decarbonization process. The technical problems of poor selection efficiency and difficult recovery of co-solvent. The carbon separated by the invention can be used as a raw material to prepare high-value carbon materials, and the auxiliary solvent can be recycled.

To achieve the above object, the present invention is achieved through the following technical solutions:

One aspect of the present invention provides a method for preparing a W/O emulsion collector for electrolytic aluminum, comprising the following steps:

Step 1: adding kerosene to alkyl glucoside or polyisobutene ethanolamine, stirring to obtain liquid product A;

Step 2: Add the KCl solution into the liquid product A and continue stirring to obtain the W/O emulsion collector.

In the above technical solution, kerosene is used as the external phase, KCl solution is used as the internal phase, and alkyl glycoside (or polyisobutene ethanolamine) is used as an emulsifier to prepare a high internal phase W/O emulsion collector. Among them, the emulsifier used is green and degradable, and the obtained emulsion has a high volume ratio of the water phase, uniform emulsion droplet size distribution, and strong stability.

Preferably, the mass ratio of kerosene to alkyl glycoside or polyisobutene ethanolamine in step 1 is 5:1-3:1.

Preferably, in the step 1, the stirring speed is 1000-2000 r/min, and the stirring time is 5-10 min.

Preferably, the mass concentration of the KCl solution in the step 2 is 6-7%; the volume ratio of the KCl solution to the liquid product A is 4:1-6:1.

As a preference, in the step 2, the KCl solution is added dropwise to the liquid product A at a constant speed of 2 to 4 mL/min, and the dropping process is accompanied by continuous stirring at a stirring speed of 1100 to 2000 r/min to prevent phase inversion of the emulsion .

Preferably, in the step 2, the stirring speed is 8000-10000 r/min, and the stirring time is 10-15 minutes, so that the particle size of the emulsion collector is uniform.

Another aspect of the present invention provides the W/O emulsion collector prepared by the above method.

Another aspect of the present invention also provides the application of the above-mentioned W/O emulsion collector in the separation of electrolytic aluminum carbon-containing solid waste, which specifically includes the following steps:

Step 1: Add electrolytic aluminum carbon slag into water, stir to obtain mixed solution B;

Step 2: Add the W/O type emulsion collector to the mixed solution B and stir to obtain the mixed solution C;

Step 3: Then add a foaming agent to the mixed solution C, pass in air for flotation separation, and scrape to obtain carbon substances.

As a preference, the solid-to-liquid mass ratio of electrolytic aluminum carbon slag to water in step 1 is 1:20 to 1:25; the mass ratio of W/O emulsion collector to mixed solution B in step 2 is 1 :33000～1:34000, the stirring speed is 1000～1200r/min, and the stirring time is 2～3min.

As preferably, in the step 3, the foaming agent is secondary octanol, and the amount of secondary octanol added is 0.4 to 0.5 times that of the W/O emulsion collector, and the conditions for flotation separation are: 1000 to 1200r Stir continuously at a speed of 1/min, the gas flow rate is controlled at 10-15mL/min, the flotation time is 5-8min, and the time interval is 10-15s for scraping.

Compared with the prior art, the beneficial effects of the present invention are as follows:

The W/O type emulsion collector provided by the present invention can realize the efficient removal and recovery of carbon resources in electrolytic aluminum carbon slag by the flotation method when the dosage is relatively low (the flotation yield of carbon reaches 80%-85%) %), while greatly reducing the content of carbon impurities in the co-solvent, and has the advantages of simple process, cost-effective and high-efficiency. The carbon obtained by flotation separation in the present invention can be used for the preparation of high-value carbon materials, and the cosolvent can be recycled and reused in the electrolytic aluminum process, which is of great significance to the sustainable development of the electrolytic aluminum industry and the resource utilization of carbon slag.

Description of drawings

Fig. 1 is a micrograph of the W/O emulsion collector of the present invention.

Detailed ways

In order to facilitate understanding of the present invention, the present invention will be described in more detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the present application, and are not intended to limit the invention.

Example 1

Preparation of W/O Type Emulsion Collector

Step 1: Add 6.25g of kerosene to 1.25g of alkyl glucoside, and stir at a speed of 1000r/min for 5min to obtain liquid product A;

Step 2: 35g of KCl solution with a mass concentration of 6% is added dropwise to the liquid product A at a constant speed of 2mL/min through a flowmeter, and the stirring is continued at a speed of 1100r/min during the dropping process until the addition of the KCl solution is completed to obtain liquid product B;

Step 3: Move the liquid product B to a high-speed mixer, and stir for 10 minutes at a speed of 8000 r/min to obtain a W/O emulsion collector. The type of emulsion was judged by dilution dispersion method and fluorescent dyeing method. The size of emulsion was measured by optical microscope and dynamic light scattering. The size of emulsion droplet was mainly distributed in the range of 10-40 μm.

Application of W/O Type Emulsion Collector

Step 1: Add 5g of electrolytic aluminum carbon slag to 100mL of water and stir for 5 minutes to make the carbon slag sample fully wet to obtain the mixed solution D;

Step 2: Add 3.1 mg of the W/O emulsion collector prepared by the above method into the mixed solution D, and continue stirring at a stirring speed of 1000 r/min for 2 minutes to obtain the mixed solution E;

Step 3: Transfer the mixed liquid E to the flotation tube, add 1.24mg of 2-octanol as a foaming agent, keep stirring at a stirring speed of 1000r/min, pass air from the bottom of the flotation tube, and control the gas flow rate to 10mL /min, flotation for 5 minutes, scrape off the foam floating to the top of the flotation tube at a time interval of 10s, perform suction filtration, wash, dry, and recycle to obtain carbon products, and the flotation yield of carbon is 80% ;

Step 4: The product remaining in the flotation tube is subjected to suction filtration, washed, dried, and recovered to obtain a co-solvent for electrolytic aluminum, and the recovery rate of the co-solvent is 88%.

Example 2

Preparation of W/O Type Emulsion Collector

Step 1: Add 4.5g of kerosene to 1.5g of polyisobutene ethanolamine (PIB), and stir at a speed of 1100r/min for 6min to obtain a liquid product A;

Step 2: 40g of KCl solution with a mass concentration of 6% is added dropwise to the liquid product A at a constant speed of 3mL/min through a flowmeter, and the stirring is continued at a speed of 1200r/min during the dropping process until the addition of the KCl solution is completed to obtain liquid product B;

Step 3: Move the liquid product B to a high-speed mixer, and stir at a speed of 9000r/min for 12 minutes to obtain a W/O emulsion collector. The emulsion type is determined by dilution dispersion and fluorescent dyeing. The size of the emulsion is determined by optical Microscope and dynamic light scattering are used to measure, and the size of emulsion droplets is mainly distributed in the range of 20-40 μm.

Application of W/O Type Emulsion Collector

Step 1: Add 6g of electrolytic aluminum carbon slag into 130mL water and stir and disperse for 6 minutes to fully wet the carbon slag sample to obtain a mixed solution D;

Step 2: Add 4.1 mg of the W/O emulsion collector prepared by the above method into the mixed solution D, and continue stirring at a stirring speed of 1100 r/min for 2 minutes to obtain the mixed solution E;

Step 3: Transfer the mixed solution E to the flotation tube, add 1.85 mg of 2-octanol as a foaming agent, keep stirring at a stirring speed of 1100 r/min, and feed air from the bottom of the flotation tube, and control the gas flow rate to 12 mL /min, flotation for 8min, scraping off the foam floating to the top of the flotation tube at a time interval of 12s, performing suction filtration, washing, drying, and recycling to obtain carbon products, and the flotation yield of carbon is 82% ;

Step 4: The product remaining in the flotation tube is suction-filtered, washed, dried, and recovered to obtain a co-solvent for electrolytic aluminum, and the recovery rate of the co-solvent is 90%.

Example 3

Preparation of W/O Type Emulsion Collector

Step 1: Add 8g of kerosene to 2g of alkyl glucoside, and stir at 1500r/min for 8min to obtain liquid product A;

Step 2: 70g of KCl solution with a mass concentration of 7% is added dropwise at a constant speed of 4mL/min to the liquid product A through a flowmeter, and stirred at a speed of 1800r/min during the dropping process until the addition of the KCl solution is completed to obtain a liquid product B;

Step 3: Move the liquid product B to a high-speed mixer, and stir at a speed of 9000r/min for 14 minutes to obtain a W/O emulsion collector. The emulsion type is determined by dilution dispersion and fluorescent dyeing. The size of the emulsion is determined by optical Microscope and dynamic light scattering were used to measure, and the size of emulsion droplets was mainly distributed in the range of 10-40 μm.

Application of W/O Type Emulsion Collector

Step 1: Add 8g of electrolytic aluminum carbon slag to 185mL ultrapure water and stir for 8 minutes to make the carbon slag sample fully wet to obtain the mixed solution D;

Step 2: Add 5.8 mg of the W/O emulsion collector prepared by the above method into the mixed solution D, and continue stirring at a stirring speed of 1200 r/min for 3 minutes to obtain the mixed solution E;

Step 3: Transfer the mixed solution E to the flotation tube, add 2.9mg of 2-octanol as a foaming agent, keep stirring at a stirring speed of 1200r/min, feed air from the bottom of the flotation tube, and control the gas flow rate to 14mL /min, flotation for 6 minutes, scrape off the foam floating to the top of the flotation tube at a time interval of 14s, perform suction filtration, wash, dry, and recycle to obtain carbon products, and the flotation yield of carbon is 85% ;

Step 4: The product remaining in the flotation tube is suction filtered, washed, dried, and recovered to obtain a cosolvent for electrolytic aluminum, and the recovery rate of the cosolvent is 93%.

Example 4

Preparation of W/O Type Emulsion Collector

Step 1: Add 10 g of kerosene to 2.5 g of polyisobutene ethanolamine, and stir at a speed of 2000 r/min for 10 min to obtain a liquid product A;

Step 2: 100g of KCl solution with a mass concentration of 6% is added dropwise at a constant speed of 4mL/min to the liquid product A through a flowmeter, and the stirring is continued at a speed of 2000r/min during the dropping process until the addition of the KCl solution is completed to obtain liquid product B;

Step 3: Move the liquid product B to a high-speed mixer and stir for 15 minutes at a speed of 10,000r/min to obtain a W/O emulsion collector. The type of emulsion is determined by dilution dispersion and fluorescent dyeing. The size of the emulsion is determined by optical Microscope and dynamic light scattering were used to measure, and the size of emulsion droplets was mainly distributed in the range of 10-30 μm.

Application of W/O Type Emulsion Collector

Step 1: Add 10g of electrolytic aluminum carbon slag into 250mL ultrapure water and stir and disperse for 10 minutes to fully wet the carbon slag sample to obtain a mixed solution D;

Step 2: Add 7.9 mg of the W/O emulsion collector prepared by the above method into the mixed solution D, and continue stirring at a stirring speed of 1200 r/min for 3 minutes to obtain the mixed solution E;

Step 3: Transfer the mixed solution E to the flotation tube, add 3.95 mg of 2-octanol as a foaming agent, keep stirring at a stirring speed of 1200 r/min, and feed air from the bottom of the flotation tube, and control the gas flow rate to 15 mL /min, flotation for 5 minutes, scrape off the foam floating to the top of the flotation tube at a time interval of 15s, perform suction filtration, wash, dry, and recover to obtain carbon products, and the flotation yield of carbon is 83% ;

Step 4: The product remaining in the flotation tube is subjected to suction filtration, washed, dried, and recovered to obtain a co-solvent for electrolytic aluminum, and the recovery rate of the co-solvent is 89%.

The technical features of the above-mentioned embodiments can be combined arbitrarily. To make the description concise, all possible combinations of the technical features in the above-mentioned embodiments are not described. However, as long as there is no contradiction in the combination of these technical features, should be considered as within the scope of this specification.

The above-mentioned embodiments only express several implementation modes of the present invention, and the descriptions thereof are relatively specific and detailed, but should not be construed as limiting the patent scope of the invention. It should be noted that those skilled in the art can make several modifications and improvements without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent for the present invention should be based on the appended claims.

Claims (10)

1. A preparation method of a W/O type emulsion collector for electrolyzing aluminum is characterized in that: the method comprises the following steps:

step 1: adding kerosene into alkyl glycoside or polyisobutene ethanolamine, and stirring to obtain a liquid product A;

step 2: and adding the KCl solution into the liquid product A, and continuously stirring to obtain the W/O type emulsion collector.

2. A method of preparing a W/O type emulsion collector for electrolytic aluminum according to claim 1, characterized in that: the mass ratio of the kerosene to the alkyl glycoside or the polyisobutene ethanolamine in the step 1 is 5-3.

3. A method of preparing a W/O type emulsion collector for electrolytic aluminum according to claim 1, characterized in that: in the step 1, the stirring speed is 1000-2000 r/min, and the stirring time is 5-10 min.

4. A method of preparing a W/O type emulsion collector for electrolytic aluminum according to claim 1, characterized in that: the mass concentration of the KCl solution in the step 2 is 6-7%; the volume ratio of the KCl solution to the liquid product A is 4.

5. A method of preparing a W/O type emulsion collector for electrolytic aluminum according to claim 1, characterized in that: and (3) dropwise adding the KCl solution into the liquid product A at a constant speed of 2-4 mL/min in the step (2), and continuously stirring in the dropwise adding process, wherein the stirring speed is 1100-2000 r/min.

6. A method of preparing a W/O type emulsion collector for electrolytic aluminum according to claim 1, characterized in that: in the step 2, the stirring speed is 8000-10000 r/min, and the stirring time is 10-15 min.

7. A W/O type emulsion collector prepared by the method of any one of claims 1 to 6.

8. The application of the W/O type emulsion collector prepared by the method of any one of claims 1 to 6 or the W/O type emulsion collector of claim 7 in the separation of solid waste containing carbon in electrolytic aluminum is characterized in that: the method comprises the following steps:

step 1: adding the electrolytic aluminum carbon slag into water, and stirring to obtain a mixed solution B;

step 2: adding the W/O type emulsion collecting agent into the mixed solution B, and stirring to obtain a mixed solution C;

and 3, step 3: and then adding a foaming agent into the mixed solution C, introducing air to perform flotation separation, and performing foam scraping to obtain a carbon substance.

9. Use of a W/O type emulsion collector according to claim 8, characterized in that: the solid-liquid mass ratio of the electrolytic aluminum carbon slag to the water in the step 1 is 1-20; the mass ratio of the W/O type emulsion collector to the mixed liquor B in the step 2 is 1.

10. Use of a W/O type emulsion collector according to claim 9, characterized in that: the conditions of flotation separation are as follows: in the step 3, the foaming agent is sec-octanol, the addition amount of the sec-octanol is 0.4 to 0.5 times of the addition amount of the W/O type emulsion collecting agent, and the conditions of flotation separation are as follows: stirring is continuously carried out at the speed of 1000-1200 r/min, the gas flow is controlled to be 10-15 mL/min, the flotation time is 5-8 min, and foam scraping is carried out at the speed of 10-15 s.

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