CN110745879A - A kind of preparation method of Mg2+ doped basic nickel carbonate microspheres - Google Patents

Abstract

The invention discloses a preparation method of Mg ²⁺ doped basic nickel carbonate microspheres. The method is realized by the following steps: 1) separately preparing a carbonate solution and a nickel salt solution; 2) adding the above two solutions at the same time In the reactor, the pH value of the control system is 7.9-8.3, and after reacting for 1-2 hours, the reaction solution is subjected to dense treatment to obtain basic nickel carbonate slurry; 3) The above basic nickel carbonate slurry is subjected to pressure filtration After removing the mother liquor, it is slurried and transferred to the reactor, and then the ethanol aqueous solution of magnesium salt is added, and the reaction is stirred to obtain Mg ²⁺ doped basic nickel carbonate slurry; 4) The above slurry is washed and baked at high temperature. Dry to get the target. The preparation process of the invention is simple and feasible, and since lattice defects are formed after Mg ²⁺ doping, the electron separation efficiency is promoted, so that the prepared Mg ²⁺ doped basic nickel carbonate microspheres have 3 higher than ordinary basic nickel carbonate. more than twice the photocatalytic performance.

Description

A kind of preparation method of Mg2+ doped basic nickel carbonate microspheres

technical field

The invention belongs to the technical field of preparation of basic nickel carbonate microspheres, in particular to a preparation method of Mg ²⁺ doped basic nickel carbonate microspheres.

Background technique

At present, domestic enterprises have two methods for synthesizing basic nickel carbonate. One synthesis method is to use ammonium carbonate or ammonium bicarbonate and nickel salt for precipitation reaction; the other is to use soda ash and nickel salt solution for precipitation reaction. The pH value needs to be adjusted to above 8.5, and the nickel can be basically precipitated completely. At this time, the amount of soda ash required is more than 35% more than the theoretical amount, and the excess alkali can not be recycled basically. The Na content in the product after material washing and drying is 300ppm Above, the operation steps are complicated, and the structure of the basic nickel carbonate prepared by the two methods is free of other doping elements, so that the obtained basic nickel carbonate has few uses.

SUMMARY OF THE INVENTION

In view of this, the main purpose of the present invention is to provide a preparation method of Mg ²⁺ doped basic nickel carbonate microspheres, which solves the problem that the basic nickel carbonate obtained in the prior art has low catalytic performance in the catalytic process.

In order to achieve the above object, the technical scheme of the present invention is achieved in this way: a preparation method of ^Mg doped basic nickel carbonate microspheres, the method is realized by the following steps:

Step 1, respectively preparing a carbonate solution with a carbonate ion concentration of 1.0 to 2.0 mol/L and a nickel salt solution with a nickel ion concentration of 0.5 to 2.0 mol/L;

In step 2, the carbonate solution and the nickel salt solution are simultaneously added to the reactor, the flow rate of the nickel salt solution is kept constant during the feeding process, and the pH value of the system is controlled to be 7.9-8.3 by adjusting the flow rate of the carbonate solution, and After reacting for 1 to 2 hours, the reaction solution is subjected to intensive treatment to continue the reaction for 8 to 18 hours to obtain basic nickel carbonate slurry;

Step 3: After the basic nickel carbonate slurry obtained in the step 2 is subjected to pressure filtration to remove the mother liquor, it is then slurried and transferred to the reaction kettle, and then the ethanol aqueous solution of magnesium salt is added to the reaction kettle, and the reaction is stirred and reacted. , to obtain Mg ²⁺ doped basic nickel carbonate slurry;

Step 4, washing the Mg ²⁺ doped basic nickel carbonate slurry obtained in the step 3, and then drying at high temperature to obtain Mg ²⁺ doped basic nickel carbonate microspheres.

Preferably, in the step 1, the carbonate is at least one of sodium carbonate, ammonium carbonate, and ammonium bicarbonate; the nickel salt is at least one of nickel sulfate, nickel chloride, and nickel nitrate.

Preferably, in the step 2, the flow rate of the sodium carbonate solution is 5-500 L/h; the flow rate of the nickel salt solution is 50-500 L/h.

Preferably, in the step 3, the Mg ²⁺ ion concentration in the ethanol aqueous solution of the magnesium salt is 0.05-0.2 mol/L, and the volume ratio of ethanol and water in the ethanol aqueous solution of the magnesium salt is 1:1.

Preferably, in the step 3, the flow rate when the ethanol aqueous solution of the magnesium salt is added is 10-15% of the flow rate of the nickel salt solution added.

Preferably, in the step 3, the molar amount of magnesium in the Mg ²⁺ doped basic nickel carbonate slurry accounts for 0.01-1% of the sum of the molar amount of magnesium and the molar amount of nickel.

Preferably, in the step 3, the magnesium salt is at least one of magnesium sulfate, magnesium chloride, and magnesium nitrate.

Preferably, in the step 3, the temperature of the stirring reaction is 50-60° C., and the time of the stirring reaction is 20-25 h.

Preferably, in the step 4, the drying temperature is 120-150°C.

Preferably, in the step 4, the drying time is 2-5h.

Compared with the prior art, the present invention has the advantages of simple operation, simple and feasible preparation process, and because of the formation of lattice defects after Mg ²⁺ doping, the electron separation efficiency is promoted, so that the prepared Mg ²⁺ doped basic nickel carbonate micro-carbonate is prepared. The ball has more than 3 times higher photocatalytic performance than ordinary basic nickel carbonate, improves the bulk density and fluidity of basic nickel carbonate, and is convenient for packaging and batch transportation.

Description of drawings

Fig. 1 is the SEM image of Mg ²⁺ doped basic nickel carbonate microspheres obtained in Example 1 of the present invention;

FIG. 2 is a schematic structural diagram of an apparatus for preparing Mg ²⁺ doped basic nickel carbonate microspheres according to an embodiment of the present invention.

Detailed ways

In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention, but not to limit the present invention.

A kind of preparation method of Mg ²⁺ doped basic nickel carbonate microspheres provided by the embodiment of the present invention, the method is realized by the following steps:

Step 1, respectively preparing a carbonate solution with a carbonate ion concentration of 1.0 to 2.0 mol/L and a nickel salt solution with a nickel ion concentration of 0.5 to 2.0 mol/L; wherein the carbonates are sodium carbonate, ammonium carbonate, carbonic acid At least one in ammonium hydrogen; nickel salt is at least one in nickel sulfate, nickel chloride, nickel nitrate;

In step 2, the peristaltic pump is used for feeding, and the carbonate solution and the nickel salt solution are added to the reactor at the same time. During the feeding process, the flow rate of the nickel salt solution is kept constant at 50-500 L/h. The pH value of the flow control system (the flow range of the sodium carbonate solution is 5 to 500 L/h) is 7.9 to 8.3, and after 1 to 2 hours of reaction, the thickener is opened (the thickener stirring rate is 5 to 10 r/min), Continue to react for 8-18h to obtain basic nickel carbonate slurry;

Step 3, after the basic nickel carbonate slurry obtained in the step 2 is subjected to pressure filtration to remove the mother liquor, it is then slurried and transferred to the reaction kettle, and then Mg ²⁺ is added to the reaction kettle. The ion concentration is 0.05～ 0.2mol/L ethanol aqueous solution of magnesium salt, stirring and reacting at 50～60℃ for 20～25h, to obtain Mg ² whose molar amount of magnesium element accounts for 0.01-1% of the sum of molar amount of magnesium element and molar amount of nickel element ⁺ Doping basic nickel carbonate slurry; wherein, the volume ratio of ethanol and water in the ethanolic solution of magnesium salt is 1:1; the flow rate when adding the ethanolic aqueous solution of magnesium salt is 10～15% of the flow rate of adding the nickel salt solution ; Magnesium salt is at least one in magnesium sulfate, magnesium chloride, magnesium nitrate;

Step 4: Wash the Mg ²⁺ doped basic nickel carbonate slurry obtained in the step 3, and then dry it at a high temperature of 120 to 150° C. for 2 to 5 hours to obtain Mg ²⁺ doped basic nickel carbonate microspheres .

The embodiment of the present invention also provides a preparation device for Mg ²⁺ doped basic nickel carbonate microspheres, which includes a reaction body 1, a dense body 2, a spin separation body 3, a reaction body 1, a dense body 2, a spin separation body 3, a reaction body 1, a dense body 2, a spin separation body 3 The separate bodies 3 are connected in sequence through pipes 4 and form a loop.

Further, the lower end sidewall of the reaction body 1 is provided with a reaction liquid outflow port 11, the bottom of the dense body 2 is provided with a reaction liquid inflow port 21, and the reaction liquid outflow port 11 is connected with the reaction liquid inflow port 21 through a pipeline and the reaction liquid flows The distance from the inlet 21 to the horizontal surface is higher than the distance from the reaction liquid outlet 11 to the horizontal surface.

Further, a first control valve 41 is provided on the pipeline 4 connecting the reaction liquid outlet 11 and the reaction liquid inlet 21 .

Further, the dense body 2 is provided with a second stirring component 22, the second stirring component 22 is located in the center of the dense body 2, and the upper end side wall of the dense body 2 is provided with a reaction liquid overflow port 23.

Further, the second stirring assembly 22 includes a second stirring motor 221, a second stirring shaft 222, and a stirring unit 223, the stirring unit 223 is fixedly connected to the lower end of the second stirring shaft 222, and the second stirring motor (221) is arranged on the second stirring shaft 222. The upper end of the stirring shaft 222 drives the second stirring shaft 222 and the stirring unit 223 to rotate around the axis. Further, the stirring unit 223 includes at least two right-angled trapezoidal stirring blades 2231, the two right-angled trapezoidal stirring blades 2231 are fixed to the lower end of the second stirring shaft 222 in a vertical direction and symmetrically, the two right-angled trapezoidal stirring blades The short sides of the vanes 2231 are provided close to the reaction liquid inlet 21 .

Further, the shape of the hypotenuse of the two right-angled trapezoidal stirring blades 2231 is adapted to the shape of the lower end of the dense body 2 .

Further, the upper end of the spin separation body 3 is provided with a supernatant overflow port 31, the side wall of the spin separation body 3 is provided with a reaction liquid overflow port 32, and the reaction liquid overflow port 32 passes through the pipeline 4 and the dense body 2. The reaction liquid overflow port 23 provided on the upper end sidewall is connected; the bottom of the spin separation and separation body 3 is provided with a solid-liquid outflow port 33, the upper end of the reaction body 1 is provided with a solid-liquid inflow port, and the solid-liquid outflow port 33 passes through the pipeline. 4 Connect with the solid-liquid flow inlet.

Further, a pneumatic diaphragm pump 42 is provided on the pipeline 4 connecting the reaction liquid overflow port 32 and the reaction liquid overflow port 23 .

Further, a second control valve 43 is provided on the pipeline connecting the solid-containing liquid outflow port 33 and the solid-containing liquid inflow port.

Further, the reaction body 1 is provided with a carbonate feed pipe 12, a nickel salt feed pipe 13, a first stirring component 14, and a pH measuring component 15, and the first stirring component 14 is located in the center of the reaction body 1, The carbonate feed pipe 12 and the nickel salt feed pipe 13 are symmetrically arranged on both sides of the reaction body 1 ; the pH measuring assembly 15 is arranged at the lower end of the reaction body 1 .

Further, the first stirring assembly 14 includes a first stirring motor 141, a first stirring shaft 142, and a first stirring blade 143. The first stirring blade 143 is fixedly connected to the lower end of the first stirring shaft 142, and the first stirring motor 141 It is arranged on the upper end of the first stirring shaft 142 and drives the first stirring shaft 142 and the first stirring blade 143 to rotate around the axis.

Further, the pH measuring assembly 15 includes a pH measuring pipeline 151 and a pH measuring instrument 152 , and the pH measuring instrument 152 is connected to the reaction body 1 through the pH measuring pipeline 151 .

Further, the outer layer of the reaction body 1 is provided with a vacuum insulation jacket 16 , the bottom of the vacuum insulation jacket 16 is provided with a condensed water inlet 161 , and the side of the vacuum insulation jacket 16 is provided with a steam outlet 162 .

Further, the bottom of the reaction body 1 is provided with a discharge port 17 and a sewage outlet 18 .

Further, two fixing brackets 19 are symmetrically arranged below the reaction body 1 .

The working principle of this device is: due to the action of gravity, the basic nickel carbonate particles will settle down and fall to the bottom of the thickener, and through low-speed stirring, the material adhering to the bottom is returned to the kettle, and the tiny particles have no time to settle out of the reaction liquid overflow port 23 It is discharged to the rotary separation body 3, the rotary separation body 3 performs rotary separation on the liquid containing small solid particles, the supernatant liquid is discharged from the supernatant liquid overflow port 31, and the solid liquid is returned to the reaction body 1, so that the kettle is The inner concentration is continuously increased to ensure the uniformity and micro-sphericity of the particle size in the kettle.

Example 1

Step 1, respectively preparing a sodium carbonate solution with a carbonate ion concentration of 1.5 mol/L and a nickel chloride solution with a nickel ion concentration of 1.2 mol/L;

Step 2, adopt peristaltic pump feeding, sodium carbonate solution and nickel chloride solution are added in the reactor simultaneously, keep the flow rate of nickel chloride solution to be 200L/h constant in the feeding process, by adjusting the flow rate of sodium carbonate solution ( The flow range of sodium carbonate solution is 5～500L/h) the pH value of the control system is 8.1±2, and after 1.5h of reaction, open the thickener (the stirring speed of the thickener is 5-10r/min), and continue to react for 15h to obtain Basic nickel carbonate slurry;

Step 3, after the basic nickel carbonate slurry obtained in step 2 is subjected to pressure filtration to remove the mother liquor, it is then slurried and transferred to the reactor, and then Mg ²⁺ ion concentration is added to the reactor to be 0.1mol/L The ethanol aqueous solution of magnesium chloride (wherein the volume ratio of ethanol and water is 1:1, and the flow rate when adding the ethanol aqueous solution of magnesium chloride is 12% of the flow rate of adding nickel chloride solution), stirring and reacting at 55 ° C for 22h to obtain magnesium Mg ²⁺ doped basic nickel carbonate slurry whose molar amount accounts for 0.1% of the sum of the molar amounts of magnesium element and nickel element;

In step 4, the Mg ²⁺ doped basic nickel carbonate slurry obtained in step 3 is washed, and then dried at a high temperature of 130° C. for 3 hours to obtain Mg ²⁺ doped basic nickel carbonate microspheres.

Example 2

Step 1, respectively preparing a sodium carbonate solution with a carbonate ion concentration of 1.0 mol/L and a nickel chloride solution with a nickel ion concentration of 0.5 mol/L;

Step 2, adopt peristaltic pump feeding, sodium carbonate solution and nickel chloride solution are added in the reactor simultaneously, keep the flow rate of nickel chloride solution to be 500L/h constant in the feeding process, by adjusting the flow rate of sodium carbonate solution ( The flow range of sodium carbonate solution is 5～500L/h) The pH value of the control system is 8.1±2, and after reacting for 1h, open the thickener (the stirring rate of the thickener is 5-10r/min), and continue to react for 8h to obtain alkali nickel carbonate slurry;

Step 3, after the basic nickel carbonate slurry obtained in step 2 is subjected to pressure filtration to remove the mother liquor, it is then slurried and transferred to the reaction kettle, and then ^Mg is added to the reaction kettle. The ion concentration is 0.05mol/L The ethanol aqueous solution of magnesium chloride (wherein, the volume ratio of ethanol to water is 1:1, and the flow rate when adding the ethanol aqueous solution of magnesium chloride is 10% of the flow rate of the nickel chloride solution), and the reaction is stirred at 50 ° C for 25h to obtain magnesium element. Mg ²⁺ doped basic nickel carbonate slurry whose molar amount accounts for 0.01% of the sum of the molar amounts of magnesium and nickel elements;

In step 4, the Mg ²⁺ doped basic nickel carbonate slurry obtained in step 3 is washed, and then dried at a high temperature of 120° C. for 5 hours to obtain Mg ²⁺ doped basic nickel carbonate microspheres.

Example 3

Step 1, prepare respectively the sodium carbonate solution that the carbonate ion concentration is 2.0mol/L and the nickel chloride solution that the nickel ion concentration is 2.0mol/L;

Step 2, adopt peristaltic pump feeding, sodium carbonate solution and nickel chloride solution are added in the reactor simultaneously, keep the flow rate of nickel chloride solution to be 5L/h constant in the feeding process, by adjusting the flow rate of sodium carbonate solution ( The flow range of the sodium carbonate solution is 5-500L/h) The pH value of the control system is 8.1±2, and after 2h of reaction, open the thickener (the stirring rate of the thickener is 5-10r/min), and continue to react for 18h to obtain alkali nickel carbonate slurry;

In step 3, after the basic nickel carbonate slurry obtained in step 2 is subjected to pressure filtration to remove the mother liquor, it is then slurried and transferred to the reaction kettle, and then Mg ²⁺ ion concentration is added to the reaction kettle to be 0.2mol/L The ethanol aqueous solution of magnesium chloride (wherein, the volume ratio of ethanol and water is 1:1, and the flow rate when adding the ethanol aqueous solution of magnesium chloride is 15% of the flow rate of the nickel chloride solution), and the reaction is stirred at 60 ° C for 20h to obtain magnesium element. The molar amount of Mg ²⁺ doped basic nickel carbonate slurry is 1% of the sum of the molar amount of magnesium element and nickel element;

In step 4, the Mg ²⁺ doped basic nickel carbonate slurry obtained in step 3 is washed, and then dried at a high temperature of 150° C. for 2 hours to obtain Mg ²⁺ doped basic nickel carbonate microspheres.

Example 4

Step 1, respectively preparing a sodium carbonate solution with a carbonate ion concentration of 1.5 mol/L and a nickel sulfate solution with a nickel ion concentration of 1.2 mol/L;

Step 2, adopt peristaltic pump to feed, add sodium carbonate solution and nickel sulfate solution to reactor simultaneously, keep the flow rate of nickel sulfate solution to be 200L/h constant in the feeding process, by adjusting the flow rate of sodium carbonate solution (sodium carbonate The flow range of the solution is 5~500L/h) The pH value of the control system is 8.1±2, and after the reaction for 1.5h, the thickener is opened (the stirring rate of the thickener is 5-10r/min), and the reaction is continued for 15h to obtain the basic formula Nickel carbonate slurry;

Step 3, after the basic nickel carbonate slurry obtained in step 2 is subjected to pressure filtration to remove the mother liquor, it is then slurried and transferred to the reaction kettle, and then ^Mg is added to the reaction kettle. The ion concentration is 0.05mol/L The ethanol aqueous solution of magnesium sulfate (wherein, the volume ratio of ethanol and water is 1:1, and the flow rate when adding the ethanol aqueous solution of magnesium sulfate is 10% of the flow rate of adding nickel sulfate solution), and the reaction is stirred at 50 ° C for 25h to obtain magnesium Mg ²⁺ doped basic nickel carbonate slurry in which the molar amount of the element accounts for 0.01% of the sum of the molar amount of the magnesium element and the nickel element;

In step 4, the Mg ²⁺ doped basic nickel carbonate slurry obtained in step 3 is washed, and then dried at a high temperature of 120° C. for 5 hours to obtain Mg ²⁺ doped basic nickel carbonate microspheres.

Example 5

Step 1, prepare respectively the ammonium carbonate solution that the carbonate ion concentration is 1.5mol/L and the nickel chloride solution that the nickel ion concentration is 1.2mol/L;

Step 2, adopt peristaltic pump feeding, ammonium carbonate solution and nickel chloride solution are added in the reactor simultaneously, keep the flow rate of nickel chloride solution to be 200L/h constant in the feeding process, by adjusting the flow rate of ammonium carbonate solution ( The flow rate range of ammonium carbonate solution is 5～500L/h) The pH value of the control system is 8.1±2, and after 1.5h of reaction, open the thickener (the stirring speed of the thickener is 5-10r/min), and continue to react for 15h to obtain Basic nickel carbonate slurry;

In step 3, after the basic nickel carbonate slurry obtained in step 2 is subjected to pressure filtration to remove the mother liquor, it is then slurried and transferred to the reaction kettle, and then Mg ²⁺ ion concentration is added to the reaction kettle to be 0.2mol/L The ethanol aqueous solution of magnesium chloride (wherein, the volume ratio of ethanol and water is 1:1, and the flow rate when adding the ethanol aqueous solution of magnesium chloride is 15% of the flow rate of the nickel chloride solution), and the reaction is stirred at 60 ° C for 20h to obtain magnesium element. The molar amount of Mg ²⁺ doped basic nickel carbonate slurry is 1% of the sum of the molar amount of magnesium element and nickel element;

In step 4, the Mg ²⁺ doped basic nickel carbonate slurry obtained in step 3 is washed, and then dried at a high temperature of 150° C. for 2 hours to obtain Mg ²⁺ doped basic nickel carbonate microspheres.

Example 6

Step 1, prepare respectively the ammonium carbonate solution that the carbonate ion concentration is 1.0mol/L and the nickel sulfate solution that the nickel ion concentration is 0.5mol/L;

Step 2, adopt peristaltic pump to feed, add sodium carbonate solution and nickel sulfate solution to reactor simultaneously, keep the flow rate of nickel sulfate solution to be 500L/h constant in the feeding process, by adjusting the flow rate of ammonium carbonate solution (ammonium carbonate The flow range of the solution is 5～500L/h) The pH value of the control system is 8.1±2, and after reacting for 1h, open the thickener (the stirring speed of the thickener is 5-10r/min), and continue to react for 8h to obtain basic carbonic acid Nickel slurry;

Step 3, after the basic nickel carbonate slurry obtained in step 2 is subjected to pressure filtration to remove the mother liquor, it is then slurried and transferred to the reactor, and then Mg ²⁺ ion concentration is added to the reactor to be 0.1mol/L The ethanol aqueous solution of magnesium sulfate (wherein the volume ratio of ethanol and water is 1:1, the flow rate when adding the ethanol aqueous solution of magnesium sulfate is 12% of the flow rate of adding nickel sulfate solution), and the reaction is stirred at 55 ° C for 22h to obtain magnesium element. The molar amount of Mg ²⁺ doped basic nickel carbonate slurry is 0.1% of the sum of the molar amount of magnesium element and nickel element;

In step 4, the Mg ²⁺ doped basic nickel carbonate slurry obtained in step 3 is washed, and then dried at a high temperature of 130° C. for 3 hours to obtain Mg ²⁺ doped basic nickel carbonate microspheres.

Example 7

Step 1, respectively preparing a sodium carbonate solution with a carbonate ion concentration of 1.0 mol/L and a nickel nitrate solution with a nickel ion concentration of 0.5 mol/L;

Step 2, adopt peristaltic pump feeding, sodium carbonate solution and nickel nitrate solution are added in the reactor simultaneously, keep the flow rate of nickel nitrate solution to be 500L/h constant in the feeding process, by adjusting the flow rate of sodium carbonate solution (sodium carbonate The flow range of the solution is 5～500L/h) The pH value of the control system is 8.1±2, and after reacting for 1h, open the thickener (the stirring speed of the thickener is 5-10r/min), and continue to react for 8h to obtain basic carbonic acid Nickel slurry;

In step 3, after the basic nickel carbonate slurry obtained in step 2 is subjected to pressure filtration to remove the mother liquor, it is then slurried and transferred to the reaction kettle, and then Mg ²⁺ ion concentration is added to the reaction kettle to be 0.2mol/L The ethanol aqueous solution of magnesium nitrate (wherein, the volume ratio of ethanol and water is 1:1, and the flow rate when adding the ethanol aqueous solution of magnesium nitrate is 15% of the flow rate of adding nickel nitrate solution), and the reaction is stirred at 60 ° C for 20h to obtain magnesium Mg ²⁺ doped basic nickel carbonate slurry in which the molar amount of the element accounts for 1% of the sum of the molar amount of the magnesium element and the nickel element;

In step 4, the Mg ²⁺ doped basic nickel carbonate slurry obtained in step 3 is washed, and then dried at a high temperature of 150° C. for 2 hours to obtain Mg ²⁺ doped basic nickel carbonate microspheres.

Example 8

Step 1, prepare respectively the ammonium carbonate solution that the carbonate ion concentration is 2.0mol/L and the nickel nitrate solution that the nickel ion concentration is 2.0mol/L;

Step 2, adopt peristaltic pump feeding, add ammonium carbonate solution and nickel nitrate solution into the reactor simultaneously, keep the flow rate of nickel nitrate solution to be 5L/h constant in the feeding process, by adjusting the flow rate of ammonium carbonate solution (ammonium carbonate The flow range of the solution is 5～500L/h) The pH value of the control system is 8.1±2, and after the reaction for 2h, the thickener is opened (the stirring rate of the thickener is 5-10r/min), and the reaction is continued for 18h to obtain basic carbonic acid Nickel slurry;

Step 3, after the basic nickel carbonate slurry obtained in step 2 is subjected to pressure filtration to remove the mother liquor, it is then slurried and transferred to the reactor, and then Mg ²⁺ ion concentration is added to the reactor to be 0.1mol/L The ethanol aqueous solution of magnesium nitrate (wherein the volume ratio of ethanol and water is 1:1, and the flow rate when adding the ethanol aqueous solution of magnesium nitrate is 12% of the flow rate of adding nickel nitrate solution), and stirring the reaction at 55 ° C for 22h to obtain magnesium element The molar amount of Mg ²⁺ doped basic nickel carbonate slurry is 0.1% of the sum of the molar amount of magnesium element and nickel element;

In step 4, the Mg ²⁺ doped basic nickel carbonate slurry obtained in step 3 is washed, and then dried at a high temperature of 130° C. for 3 hours to obtain Mg ²⁺ doped basic nickel carbonate microspheres.

Example 9

Step 1, prepare respectively the ammonium bicarbonate solution that the carbonate ion concentration is 2.0mol/L and the nickel chloride solution that the nickel ion concentration is 2.0mol/L;

Step 2, using peristaltic pump feeding, adding ammonium bicarbonate solution and nickel chloride solution into the reactor at the same time, keeping the flow rate of nickel chloride solution unchanged at 5L/h during the feeding process, by adjusting the Flow (the flow range of ammonium bicarbonate solution is 5～500L/h), the pH value of the control system is 8.1±2, and after reacting for 2h, open the thickener (the stirring rate of the thickener is 5-10r/min), and continue the reaction for 18h , to obtain basic nickel carbonate slurry;

Step 3, after the basic nickel carbonate slurry obtained in step 2 is subjected to pressure filtration to remove the mother liquor, it is then slurried and transferred to the reaction kettle, and then ^Mg is added to the reaction kettle. The ion concentration is 0.05mol/L The ethanol aqueous solution of magnesium chloride (wherein, the volume ratio of ethanol to water is 1:1, and the flow rate when adding the ethanol aqueous solution of magnesium chloride is 10% of the flow rate of the nickel chloride solution), and the reaction is stirred at 50 ° C for 25h to obtain magnesium element. Mg ²⁺ doped basic nickel carbonate slurry whose molar amount accounts for 0.01% of the sum of the molar amounts of magnesium and nickel elements;

In step 4, the Mg ²⁺ doped basic nickel carbonate slurry obtained in step 3 is washed, and then dried at a high temperature of 120° C. for 5 hours to obtain Mg ²⁺ doped basic nickel carbonate microspheres.

Performance testing experiment:

The Mg ²⁺ doped basic nickel carbonate microspheres obtained in Example 1 to Example 9 are tested for performance, and the test results are as follows:

Table 1 Comparative data of decomposition rate of Mg ²⁺ doped basic nickel carbonate microspheres to methylene blue solution obtained in Example 1 to Example 9

Methylene blue solution concentration Methylene blue concentration after photodegradation Decomposition rate (%) Example 1 10mg/L 2.1 79 Example 2 10mg/L 2.4 76 Example 3 10mg/L 1.8 82 Example 4 10mg/L 2.0 80 Example 5 10mg/L 2.2 78 Example 6 10mg/L 1.9 81 Example 7 10mg/L 2.3 77 Example 8 10mg/L 1.6 84 Example 9 10mg/L 1.7 83 Comparative ratio 10mg/L 7.2 28

Can draw from Table 1: the photocatalytic performance of the basic nickel carbonate microspheres obtained by the present invention is better than that of ordinary basic nickel carbonate, and its photocatalytic efficiency has improved more than 3 times;

The invention is easy to operate, the preparation process is simple and feasible, and since the lattice defects are formed after Mg ²⁺ doping, the electron separation efficiency is promoted, and its loose packing density is measured to be as high as 1.2 g/cm ³ or more, and at the same time, the prepared Mg ²⁺ Doped basic nickel carbonate microspheres have more than 3 times higher photocatalytic performance than ordinary basic nickel carbonate, and at the same time increase the bulk density and fluidity of basic nickel carbonate, which is convenient for packaging and batch transportation, and also extends the In the field of photocatalysis, it has strong light absorption ability, excites photogenerated carrier pairs, and improves the photocatalytic performance; and by doping Mg element, the number of oxygen vacancies is increased, the catalytic performance is improved, and the basic carbonic acid is also increased. Nickel in catalysis and other applications.

The above descriptions are merely preferred embodiments of the present invention, and are not intended to limit the protection scope of the present invention.

Claims (10)

1. Mg²⁺The preparation method of the doped basic nickel carbonate microspheres is characterized by comprising the following steps:

step 1, respectively preparing a carbonate solution with carbonate ion concentration of 1.0-2.0 mol/L and a nickel salt solution with nickel ion concentration of 0.5-2.0 mol/L;

step 2, adding a carbonate solution and a nickel salt solution into a reactor simultaneously, keeping the flow rate of the nickel salt solution unchanged in the feeding process, adjusting the pH value of a flow control system of the carbonate solution to be 7.9-8.3, reacting for 1-2 h, then carrying out thickening treatment on the reaction solution, and continuing to react for 8-18 h to obtain basic nickel carbonate slurry;

and 3, performing filter pressing on the basic nickel carbonate slurry obtained in the step 2 to remove the mother liquor, pulping, transferring to a reaction kettle, adding an ethanol water solution of magnesium salt into the reaction kettle, and stirring for reaction to obtain Mg²⁺Doping basic nickel carbonate slurry;

step 4, the Mg obtained in the step 3 is treated²⁺Washing the basic nickel carbonate doped slurry, and drying at high temperature to obtain Mg²⁺Doping basic nickel carbonate microspheres.

2. Mg according to claim 1²⁺The preparation method of the basic nickel carbonate doped microspheres is characterized in that in the step 1, the carbonate is at least one of sodium carbonate, ammonium carbonate and ammonium bicarbonate; the nickel salt is at least one of nickel sulfate, nickel chloride and nickel nitrate.

3. Mg according to claim 2²⁺The preparation method of the doped basic nickel carbonate microspheres is characterized in that in the step 2, the basic nickel carbonate microspheres are preparedThe flow rate of the sodium carbonate solution is 5-500L/h; the flow rate of the nickel salt solution is 50-500L/h.

4. Mg according to claim 3²⁺The preparation method of the doped basic nickel carbonate microspheres is characterized in that in the step 3, Mg is contained in the ethanol water solution of the magnesium salt²⁺The ion concentration is 0.05-0.2 mol/L, and the volume ratio of ethanol to water in the ethanol aqueous solution of the magnesium salt is 1: 1.

5. Mg according to claim 4²⁺The preparation method of the basic nickel carbonate doped microspheres is characterized in that in the step 3, the flow rate of the magnesium salt added ethanol water solution is 10-15% of the flow rate of the nickel salt solution added.

6. Mg according to claim 5²⁺The preparation method of the basic nickel carbonate doped microspheres is characterized in that in the step 3, the Mg²⁺The molar weight of the magnesium element in the basic nickel carbonate slurry is 0.01-1% of the sum of the molar weight of the magnesium element and the molar weight of the nickel element.

7. Mg according to claim 6²⁺The preparation method of the doped basic nickel carbonate microspheres is characterized in that in the step 3, the magnesium salt is at least one of magnesium sulfate, magnesium chloride and magnesium nitrate.

8. Mg according to claim 7²⁺The preparation method of the doped basic nickel carbonate microspheres is characterized in that in the step 3, the stirring reaction temperature is 50-60 ℃, and the stirring reaction time is 20-25 h.

9. Mg according to claim 8²⁺The preparation method of the basic nickel carbonate doped microspheres is characterized in that in the step 4, the drying temperature is 120-150 ℃.

10. Mg according to any one of claims 1 to 9²⁺The preparation method of the doped basic nickel carbonate microspheres is characterized in that in the step 4, the drying time is 2-5 hours.

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