Method for preparing titanium dioxide through plant acid hydrolysis

[0020] Example 1

[0021]First, select fresh Artemisia annua, cut off the roots, wash them with water, and place them in the sun for 5 days, then place them in a 70°C oven to dry for 24 hours. Sieve to get 80 mesh Artemisia annua powder, then mix Artemisia annua powder and methanol with a mass fraction of 60% at a mass ratio of 1:10, extract for 8 hours, collect the filtrate, repeat the extraction for 4 times, combine the filtrate and make a It is evaporated and concentrated to 1/2 of the original volume; then the concentrated filtrate and the sodium hydroxide solution with a mass fraction of 10% are stirred and mixed for 24 hours in a mass ratio of 1:1, and adjusted by a mass fraction of 95% concentrated hydrochloric acid Its pH reaches 1.5. After the pH adjustment is completed, an acid hydrolyzed solution of Artemisia annua is obtained. Diethyl ether is added to the acid hydrolyzed solution of Artemisia annua in a volume ratio of 1:1. The crystals were freeze-dried at -15°C, and artemisinic acid crystals were collected; the collected artemisinic acid crystals and deionized water were mixed and stirred at 85°C in a mass ratio of 10:1 until they were completely dissolved, to obtain green artemisinic acid. Artemisinic acid solution, then select titanium concentrate with a titanium content of 50%, place it in a 15MPa grinding device and grind it into titanium concentrate particles with a particle size of 0.2mm, and then grind the titanium concentrate with a mass ratio of 1:5. The concentrate particles and the artemisinic acid solution are stirred and mixed, and the titanic acid solution is prepared by fully reacting for 3 hours; then, polyacrylamide is added to the above-mentioned titanic acid solution at a mass ratio of 1:1000, and it is flocculated for 30 minutes, filtered and collected. The filtrate was cooled and crystallized at 7°C, and then centrifuged at 13,000 r/min for 15 min, the supernatant was collected and rotary evaporated to 1/2 of the original volume; the supernatant after rotary evaporation was heated and waited for After the temperature rises to 96°C, at a rate of 0.2°C/min, the temperature is slowly stirred at a speed of 2000r/min until it is completely boiled. After the solution begins to turn from pale yellow to grayish white, the heating and stirring are stopped, and it is allowed to mature for 2h for the first time. ; After the primary curing is completed, it is stirred and heated to complete boiling again, and after keeping boiling for 15 minutes, the heating and stirring are stopped, and it is allowed to cool naturally and filter it with suction. After collecting the filter residue and washing it with deionized water 3 times, the washing The resulting metatitanic acid was dried in a 90°C oven for 24 hours; after the drying was completed, the metatitanic acid was placed in a muffle furnace, heated to 190°C, kept for 40 minutes, and then heated to 210°C for 30 minutes. , natural cooling and grinding and sieving to obtain 80 meshes of hydrolyzed titanium dioxide with plant acid. First, put the water into the high-speed mixer, add the bactericide, thickener, pigment dispersant and titanium dioxide in sequence at low speed. After mixing evenly, slowly add the pigment and filler to the vortex stirred by the impeller, and finish adding the pigment. Then, increase the speed of the impeller, add the emulsion at a low speed, then adjust the viscosity with water or thickener solution, and sieve the material to make the coating. The coatings prepared with titanium dioxide have bright colors, high covering power, strong tinting power, and the stability of the medium can play a protective role, and can enhance the mechanical strength and adhesion of the paint film, prevent the penetration of ultraviolet rays and moisture, and prolong the paint film. life.

[0022] Example 2

[0023] First, select fresh Artemisia annua, cut off the roots, wash them with water, and place them in the sun for 3 days. Then, they are placed in a 60°C oven to dry for 20 hours. Sieve to get 60 mesh Artemisia annua powder, then mix Artemisia annua powder and methanol with a mass fraction of 60% at a mass ratio of 1:10, extract for 7 hours, collect the filtrate, repeat the extraction for 3 times, combine the filtrate and make a It is evaporated and concentrated to 1/2 of the original volume; then the concentrated filtrate and the sodium hydroxide solution with a mass fraction of 10% are stirred and mixed for 20 hours in a mass ratio of 1:1, and adjusted by a mass fraction of 95% concentrated hydrochloric acid Its pH reaches 1.0. After the pH adjustment is completed, an acid hydrolyzed solution of Artemisia annua is obtained. Diethyl ether is added to the acid hydrolyzed solution of Artemisia annua in a volume ratio of 1:1. The crystals were freeze-dried at -20°C, and the artemisinic acid crystals were collected; the collected artemisinic acid crystals and deionized water were mixed and stirred at 80°C in a mass ratio of 10:1 until they were completely dissolved. Artemisinic acid solution, then select titanium concentrate with a titanium content of 40%, place it in a 10MPa grinding device and grind it into titanium concentrate particles with a particle size of 0.1mm, and then grind the titanium concentrate with a mass ratio of 1:5. The concentrate particles and the artemisinic acid solution are stirred and mixed, and the titanic acid solution is prepared by making them fully react for 2 hours; then polyacrylamide is added to the above-mentioned titanic acid solution at a mass ratio of 1:1000, and it is flocculated for 20 minutes, filtered and collected. The filtrate was cooled and crystallized at 5°C, and then centrifuged at 12,000 r/min for 10 min, and the supernatant was collected and rotary evaporated to 1/2 of the original volume; the supernatant after rotary evaporation was heated and waited. After the temperature rises to 94°C, at a rate of 0.2°C/min, slowly stir and heat up at a speed of 1800r/min until it is completely boiled. After the solution begins to turn from pale yellow to grayish white, stop heating and stirring, and let it mature for 1h for the first time. ; After the primary curing is completed, stir it again and heat it up to complete boiling, and keep boiling for 10 min, stop heating and stirring, let it cool naturally and filter it with suction, collect the filter residue and wash it with deionized water for 2 times. The resulting metatitanic acid was dried in an oven at 80°C for 20 hours; after the drying was completed, the metatitanic acid was placed in a muffle furnace, heated to 180°C, kept for 30 minutes, and then heated to 200°C for 20 minutes , natural cooling and grinding and sieving to obtain a 60-mesh hydrolyzed titanium dioxide with plant acid. First, put the water into the high-speed mixer, add the bactericide, thickener, pigment dispersant and titanium dioxide in sequence at low speed. After mixing evenly, slowly add the pigment and filler to the vortex stirred by the impeller, and finish adding the pigment. Then, increase the speed of the impeller, add the emulsion at a low speed, then adjust the viscosity with water or thickener solution, and sieve the material to make the coating. The coatings prepared with titanium dioxide have bright colors, high covering power, strong tinting power, and the stability of the medium can play a protective role, and can enhance the mechanical strength and adhesion of the paint film, prevent the penetration of ultraviolet rays and moisture, and prolong the paint film. life.

[0024] Example 3

[0025] First, select fresh Artemisia annua, cut off the roots, wash them with water, and place them in the sun for 4 days. Then, they are placed in a 65°C oven to dry for 22 hours. Sieve to get 65 mesh Artemisia annua powder, and then mix Artemisia annua powder and methanol with a mass fraction of 60% at a mass ratio of 1:10, extract for 7 hours, collect the filtrate, repeat the extraction for 3 times, combine the filtrate and analyze the same. It is evaporated and concentrated to 1/2 of the original volume; then the concentrated filtrate and the sodium hydroxide solution with a mass fraction of 10% are stirred and mixed for 23 hours in a mass ratio of 1:1, and adjusted by a mass fraction of 95% concentrated hydrochloric acid Its pH reaches 1.0. After the pH adjustment is completed, an acid hydrolyzed solution of Artemisia annua is obtained. Diethyl ether is added to the acid hydrolysis solution of Artemisia annua in a volume ratio of 1:1. The crystals were freeze-dried at -17°C, and artemisinic acid crystals were collected; the collected artemisinic acid crystals and deionized water were mixed and stirred at 82°C in a mass ratio of 10:1 until they were completely dissolved, to obtain green artemisinic acid. Artemisinic acid solution, then select titanium concentrate with a titanium content of 45%, place it in a 12MPa grinding device and grind it into titanium concentrate particles with a particle size of 0.15mm, and then grind the titanium concentrate with a mass ratio of 1:5. The concentrate particles and the artemisinic acid solution were stirred and mixed, and the titanic acid solution was prepared by making them fully react for 2 hours; then, polyacrylamide was added to the above-mentioned titanic acid solution at a mass ratio of 1:1000, and then flocculated for 25 minutes, filtered and collected. The filtrate was cooled and crystallized at 6°C, and then centrifuged at 12,500 r/min for 13 min. The supernatant was collected and rotary evaporated to 1/2 of the original volume; the supernatant after rotary evaporation was heated and waited for After the temperature rises to 95°C, at a rate of 0.2°C/min, the temperature is slowly stirred at a speed of 1900r/min until it is completely boiled. After the solution begins to turn from pale yellow to grayish white, the heating and stirring are stopped, and the initial curing is performed for 1h. ; After the primary curing is completed, stir it again and heat it up to complete boiling, and keep boiling for 12 min, stop heating and stirring, allow it to cool naturally and filter it with suction, collect the filter residue and wash it twice with deionized water, then wash The resulting metatitanic acid was dried in an oven at 85 °C for 23 hours; after the drying was completed, the metatitanic acid was placed in a muffle furnace, and the temperature was raised to 185 °C. , Natural cooling and grinding and sieving to obtain a 70-mesh hydrolyzed titanium dioxide with vegetable acid. First, put the water into the high-speed mixer, add the bactericide, thickener, pigment dispersant, and titanium dioxide in sequence at low speed. After mixing evenly, slowly add the pigment and filler to the vortex stirred by the impeller, and finish adding the pigment. Then, increase the speed of the impeller, add the emulsion at a low speed, then adjust the viscosity with water or thickener solution, and sieve the material to make the coating. The coatings prepared with titanium dioxide have bright colors, high covering power, strong tinting power, and the stability of the medium can play a protective role, and can enhance the mechanical strength and adhesion of the paint film, prevent the penetration of ultraviolet rays and moisture, and prolong the paint film. life.