Method for preparing basic zinc chloride

Abstract

The present invention relates to a method for preparing basic zinc chloride, comprising the following steps: A: preparing raw materials: preparing zinc chloride solution, ammonia water and an induction system; B: performing synthesis: adding the zinc chloride solution and the ammonia water into the induction system in a parallel flow manner, and controlling the temperature to be 60.0-90.0° C.; after the feeding is finished, continuing to react for 20.0-40.0 minutes; and C: performing filtration, washing and drying: after filtering and washing the synthesized basic zinc chloride, drying the basic zinc chloride for 4.0-8.0 hours at 80-105° C. to obtain the basic zinc chloride product. Compared with the prior art, the method for preparing basic zinc chloride has such advantages as simple process, low impurity content, easy-to-control product quality, and suitability for industrialization.

Claims

1. A method for preparing basic zinc chloride, comprising: preparing zinc chloride solution, ammonia water, and an induction system; performing synthesis to obtain basic zinc chloride by feeding the zinc chloride solution and the ammonia water into the induction system in a parallel flow manner at a temperature of 60.0-90.0° C., continuing to react for 20.0-40.0 minutes after the feeding is completed; and filtering and washing the basic zinc chloride, and then drying the basic zinc chloride for 4.0-8.0 hours at 80-105° C. to obtain a basic zinc chloride product, wherein a zinc content of the zinc chloride solution is 50.0-150.0 g/L; the ammonia water is prepared from an industrial grade ammonia water and contains 45.0-95.0 g/L of NH.sub.3; the induction system is hydrochloric acid solution containing an inducer, and the induction system has a pH of 0-5.0; the inducer is a chlorinated or brominated quaternary ammonium salt; the inducer is added to an amount of 0.005%-1.0% based on the total mass of a reaction system; and a molar ratio of the zinc chloride solution to the ammonia water is 0.5:1- 0.65:1.

2. The method for preparing basic zinc chloride according to claim 1, wherein the zinc chloride solution is formed by dissolving and purifying industrial grade zinc chloride, or is obtained from an industrial grade zinc-containing waste material that undergoes leaching and impurity removal.

3. The method for preparing basic zinc chloride according to claim 1, wherein the pH of the induction system is 0-3.0.

4. The method for preparing basic zinc chloride according to claim 1, wherein inducer is added to an amount of 0.01%-0.5% based on the total mass of the reaction system.

5. A method for preparing basic zinc chloride, comprising: preparing zinc chloride solution, ammonia water containing an inducer, and hydrochloric acid solution; performing synthesis to obtain a basic zinc chloride by feeding the zinc chloride solution and the ammonia water containing an inducer into the hydrochloric acid solution in a parallel flow manner at a temperature of 60.0-90.0° C., continuing to react for 20.0-40.0 minutes after the feeding is completed; and filtering and washing the basic zinc chloride, and then drying the basic zinc chloride for 4.0-8.0 hours at 80-105° C. to obtain a basic zinc chloride product, wherein a zinc content of the zinc chloride solution is 50.0-150.0 g/L; the ammonia water containing an inducer is obtained from dissolving the inducer in an ammonia water, the ammonia water is prepared from an industrial grade ammonia water and contains 45.0-95.0 g/L of NH.sub.3; the inducer is a chlorinated or brominated quaternary ammonium salt; the inducer is added to an amount of 0.005%-1.0% based on the total mass of a reaction system; and a molar ratio of the zinc chloride solution to the ammonia water is 0.5:1- 0.65:1.

6. The method for preparing basic zinc chloride according to claim 5, wherein the inducer is a quaternary ammonium salt that is at least one compound selected from the group consisting of tetrabutylammonium chloride, tetrabutylammonium bromide, cetyl trimethyl ammonium chloride, cetyl trimethyl ammonium bromide, octadecyl trimethyl ammonium chloride, and octadecyl trimethyl ammonium bromide.

7. The method for preparing basic zinc chloride according to claim 1, wherein the inducer is a quaternary ammonium salt that is at least one compound selected from the group consisting of tetrabutylammonium chloride, tetrabutylammonium bromide, cetyl trimethyl ammonium chloride, cetyl trimethyl ammonium bromide, octadecyl trimethyl ammonium chloride, and octadecyl trimethyl ammonium bromide.

Description

BRIEF DESCRIPTION OF DRAWINGS

(1) FIG. 1 is a particle size distribution diagram of a basic zinc chloride product prepared according to Embodiment 1;

(2) FIG. 2 is a particle size distribution diagram of a basic zinc chloride product prepared according to Embodiment 2;

(3) FIG. 3 is a particle size distribution diagram of a basic zinc chloride product prepared according to Embodiment 3;

(4) FIG. 4 is an X-ray diffraction (XRD) analysis diagram of the basic zinc chloride product prepared according to Embodiment 3;

(5) FIG. 5 is a scanning electron microscope (SEM) diagram (100 fold) of the basic zinc chloride product prepared according to Embodiment 3; and

(6) FIG. 6 is an SEM diagram (5000 fold) of the basic zinc chloride product prepared according to Embodiment 3.

DESCRIPTION OF EMBODIMENTS

(7) Further detailed description is performed below in combination with optimal embodiments as shown in accompanying drawings.

(8) A method for preparing basic zinc chloride according to the present invention comprises the following steps:

(9) A: preparing raw materials: preparing zinc chloride solution, ammonia water and an induction system, wherein the zinc content of the zinc chloride solution is 50.0-150.0 g/L; the ammonia water is prepared from industrial grade ammonia water, and the concentration of NH.sub.3 is 45.0-95.0 g/L; the induction system is hydrochloric acid solution where an inducer is dissolved, and the pH is 0-5.0 and is most preferably 0-3.0; the inducer is a chlorinated or brominated quaternary ammonium salt, and the quaternary ammonium salt comprises tetrabutylammonium chloride, tetrabutylammonium bromide, cetyl trimethyl ammonium chloride, cetyl trimethyl ammonium bromide, octadecyl trimethyl ammonium chloride or octadecyl trimethyl ammonium bromide; the additive amount of the inducer is 0.005%-1.0% and is most preferably 0.01%-0.5%; the molar ratio of the zinc chloride solution to the ammonia water is 0.5:1-0.65:1; and the zinc chloride solution is formed by dissolving and purifying industrial grade zinc chloride, or is formed by causing industrial grade zinc-containing waste materials to undergo leaching and impurity removal (the contents of impurities such as Fe, Mn, Pb, Cd, Hg and As are all lower than 5.0 mg/L);

(10) B: performing synthesis: adding the zinc chloride solution and the ammonia water into the induction system in a parallel flow manner, and controlling the temperature to be 60.0-90.0° C.; after the feeding is finished, continuing to react for 20.0-40.0 minutes; and

(11) C: performing filtration, washing and drying: after filtering and washing the synthesized basic zinc chloride, drying the basic zinc chloride for 4.0-8.0 hours at 80-105° C. to obtain the basic zinc chloride product.

(12) After the step C, as required, the basic zinc chloride product undergoes chemical composition, X diffraction, scanning electron microscope and laser particle size analysis, etc.

(13) In the implementing process, the inducer may be directly dissolved in the ammonia water.

(14) Embodiment 1

(15) Prepare hydrochloric acid with a concentration of 1.0 mol/L, zinc chloride solution with a concentration of 97.6 g/L and ammonia water with an NH.sub.3 content of 68.0 g/L, and dissolve 0.1 g of octadecyl trimethyl ammonium bromide in the ammonia water; first transfer 100.0 ml of the hydrochloric acid into a 2000.0 ml reactor, stir and heat the hydrochloric acid, control the temperature to be about 58.0° C.; add 270.0 ml of ammonia water and 416.2 ml of zinc chloride into the reactor in a parallel flow manner; after the feeding is finished, continue to react for half an hour, perform filtration and washing, and finally dry the basic zinc chloride for 6.0 hours at 90.0° C. to obtain the basic zinc chloride product.

(16) Perform ingredient and particle size analysis on the finished product, the result indicates that the percentage of Zn is 58.8%, the percentage of Cl is 12.0%, the Pb concentration is 3.5 ppm, the Cd concentration is 4.0 ppm and the As concentration is 3.17 ppm; the chemical indexes meet the national standard requirements for feed grade basic zinc chloride; the specific surface area is 0.523 m.sup.2/g, the volume average particle size is 22.063 μm, d(0.1) 5.422 μm, d(0.5) 18.037 μm and d(0.9) 47.961 μm, and the specific particle size distribution is as shown in FIG. 1.

(17) Embodiment 2

(18) Prepare hydrochloric acid with a concentration of 0.25 mol/L, zinc chloride solution with a concentration of 110.0 g/L and ammonia water with an NH.sub.3 content of 85.0 g/L, and dissolve 0.35 g of cetyl trimethyl ammonium chloride in the hydrochloric acid; first transfer 200.0 ml of the hydrochloric acid into a 2000.0 ml reactor, stir and heat the hydrochloric acid, control the temperature to be about 70.0° C.; add 250.0 ml of ammonia water and 450.0 ml of zinc chloride into the reactor in a parallel flow manner; after the feeding is finished, continue to react for half an hour, perform filtration and washing, and finally dry the basic zinc chloride for 10.0 hours at 85.0° C. to obtain the basic zinc chloride product.

(19) Perform ingredient and particle size analysis on the finished product, the result indicates that the percentage of Zn is 59.5%, the percentage of Cl is 12.6%, the Pb concentration is lower than 3.5 ppm, the Cd concentration is lower than 4.0 ppm and the As concentration is 7.78 ppm; the chemical indexes meet the national standard requirements for feed grade basic zinc chloride; the specific surface area is 0.257 m.sup.2/g, the volume average particle size is 96.913 μm, d(0.1) 8.209 μm, d(0.5) 66.367 μm and d(0.9) 195.707 μm, and the specific particle size distribution is as shown in FIG. 2.

(20) Embodiment 3

(21) Prepare hydrochloric acid with a concentration of 0.05 mol/L, zinc chloride solution with a concentration of 135.0 g/L and ammonia water with an NH.sub.3 content of 72.0 g/L, and dissolve 0.5 g of cetyl trimethyl ammonium bromide in the hydrochloric acid; first transfer 600.0 ml of the hydrochloric acid into a 2000.0 ml reactor, stir and heat the hydrochloric acid, control the temperature to be about 82.0° C.; add 310.0 ml of ammonia water and 360.0 ml of zinc chloride into the reactor in a parallel flow manner; after the feeding is finished, continue to react for half an hour, perform filtration and washing, and finally dry the basic zinc chloride for 3.5 hours at 105.0° C. to obtain the basic zinc chloride product.

(22) Perform ingredient, particle size and microstructure analysis on the finished product, the result indicates that the percentage of Zn is 58.6%, the percentage of Cl is 12.1%, the Pb concentration is lower than 3.5 ppm, the Cd concentration is lower than 4.0 ppm and the As concentration is 1.13 ppm; the chemical indexes meet the national standard requirements for feed grade basic zinc chloride; the specific surface area is 0.154 m.sup.2/g, the volume average particle size is 103.873 μm, d(0.1) 38.92 μm, d(0.5) 70.987 μm and d(0.9) 131.553 μm, and the specific particle size distribution is as shown in FIG. 3. FIG. 4 is the XRD analysis diagram of the product; and FIG. 5 and FIG. 6 are SEM diagrams of the product prepared according to Embodiment 3 and amplified by 100 fold and 5000 fold.