Preparation method of high-activity crystal seed by hydrolysis of titanium sulfate solution

Abstract

The invention discloses a preparation method of high-activity crystal seed by hydrolysis of a titanium sulfate solution and belongs to the technical field of production of titanium dioxide by a sulfuric acid method. The preparation method comprises the following steps of (A) taking and putting a hydrolytic titanium sulfate solution into a preheating groove to be preheated to 50-65 DEG C, wherein the concentration of TiO2 in the hydrolytic titanium sulfate solution is 195-205g / L, the concentration of Ti<3+> is 1.0-3.0g / L (calculated by TiO2), the concentration ratio F between effective acid andtotal TiO2 is 1.70-1.85, the concentration ratio between Fe and TiO2 is 0.26-0.31, the solid content is less than 30mg / L, and the stability is greater than or equal to 500; (B) preheating alkaline liquid to 50-65 DEG C, and controlling the concentration of the preheated alkaline liquid to 8.0-8.5%; (C) within 1-4 minutes, adding the hydrolytic titanium sulfate solution into the alkaline liquid, and after the reaction is finished, controlling the temperature of the crystal seed titanium sulfate solution to be 40-60 DEG C; (D) diluting and controlling the concentration of TiO2 in the crystal seed titanium sulfate solution to be 30-160g / L. The crystal seed prepared by the method is high in activity, less in added amount in water crystallization and high in hydrolysis rate, and the obtained hydrated titanium dioxide is uniform in particle size distribution.

Description

technical field

[0001] The invention belongs to the technical field of sulfuric acid titanium dioxide production, and relates to a preparation method for hydrolyzing high-activity crystal seeds of titanium sulfate solution. The seed crystal prepared by the method of the invention has high activity, small addition amount to water crystal, high hydrolysis rate, and the obtained hydrated titanium dioxide has uniform particle diameter. Background technique

[0002] In the process of producing titanium dioxide for decorative base paper by sulfuric acid method, hydrolysis of titanium sulfate solution to prepare hydrated titanium dioxide is the central link. Hydrolysis should not only consider the complete degree of hydrolysis, that is, the hydrolysis rate, but more importantly, the particle size and particle size distribution of suitable hydrated titanium dioxide, which determine the pigment performance and optical performance of titanium dioxide.

[0003] There are two methods f...

Examples

Embodiment 1

[0026] (1) Preheating of the titanium sulfate solution: the volume ratio of the hydrolyzed titanium sulfate solution is 1.0%, and the temperature of the titanium sulfate solution is 50°C. Titanium Sulfate Liquid TiO 2 Concentration 197.54g / L; Ti 3+ 1.67g / L (as TiO 2 count); effective acid and total TiO 2 Concentration ratio F 1.70; Fe / TiO 2 0.28; solid content 21mg / L; stability 500.

[0027] (2) Preheating of lye: in the hydrolysis preparation tank, the temperature of sodium hydroxide solution is 50°C, the concentration is 8.2%, and the amount of lye is controlled to control the seed acid ratio F=0.35.

[0028] (3) Neutralization: within 1 minute, add the titanium sulfate solution to the alkali solution, and the reaction time is 80 minutes. After the reaction, the temperature of the seed crystal was 42°C.

[0029] ⑷Dilution: add water to dilute, control seed TiO 2 The concentration is 35.54g / L. After standing for 50 days, it can still be used as hydrolysis seed crystal...

Embodiment 2

[0031] (1) Titanium sulfate solution: hydrolyze the titanium sulfate solution according to the volume ratio of 0.5%, and the temperature of the titanium sulfate solution is 60°C. Titanium Sulfate Liquid TiO 2 Concentration 201.46g / L; Ti 3+ 1.89g / L (as TiO 2 count); effective acid and total TiO 2 Concentration ratio F 1.80; Fe / TiO 2 0.30; solid content 28mg / L; stability 550.

[0032] (2) Preheating of lye: in the hydrolysis preparation tank, the temperature of sodium hydroxide solution is 60°C, the concentration is 8.4%, and the amount of lye is controlled to control the seed acid ratio F=0.45.

[0033] (3) Neutralization: within 2 minutes, add the titanium sulfate solution to the alkali solution, and the reaction time is 70 minutes. After the reaction, the temperature of the seed crystal was 50°C.

[0034] ⑷Dilution: add water to dilute, control seed TiO 2 The concentration is 50.25g / L. After standing for 60 days, it can still be used as hydrolysis seed crystal.

Embodiment 3

[0036] ⑴Titanium sulfate liquid: according to the volume ratio of hydrolyzed titanium sulfate liquid 0.8%, the temperature of titanium sulfate liquid is 65 ℃. Titanium Sulfate Liquid TiO 2 Concentration 200.16g / L; Ti 3+ 2.5g / L (as TiO 2 count); effective acid and total TiO 2 Concentration ratio F 1.85; Fe / TiO 2 0.29; solid content 22mg / L; stability 550.

[0037] (2) Preheating of lye: in the hydrolysis preparation tank, the temperature of sodium hydroxide solution is 65°C, the concentration is 8.0%, and the amount of lye is controlled to control the seed acid ratio F=0.40.

[0038] (3) Neutralization: within 2 minutes, add the titanium sulfate solution to the alkali solution, and the reaction time is 60 minutes. After the reaction, the temperature of the seed crystal was 55°C.

[0039] ⑷Dilution: add water to dilute, control seed TiO2 The concentration is 53.18g / L. After standing for 47 days, it can still be used as hydrolysis seed crystal.

technical field

[0001] The invention belongs to the technical field of sulfuric acid titanium dioxide production, and relates to a preparation method for hydrolyzing high-activity crystal seeds of titanium sulfate solution. The seed crystal prepared by the method of the invention has high activity, small addition amount to water crystal, high hydrolysis rate, and the obtained hydrated titanium dioxide has uniform particle diameter. Background technique

[0002] In the process of producing titanium dioxide for decorative base paper by sulfuric acid method, hydrolysis of titanium sulfate solution to prepare hydrated titanium dioxide is the central link. Hydrolysis should not only consider the complete degree of hydrolysis, that is, the hydrolysis rate, but more importantly, the particle size and particle size distribution of suitable hydrated titanium dioxide, which determine the pigment performance and optical performance of titanium dioxide.

[0003] There are two methods f...

Examples

Embodiment 1

[0026] (1) Preheating of the titanium sulfate solution: the volume ratio of the hydrolyzed titanium sulfate solution is 1.0%, and the temperature of the titanium sulfate solution is 50°C. Titanium Sulfate Liquid TiO 2 Concentration 197.54g / L; Ti 3+ 1.67g / L (as TiO 2 count); effective acid and total TiO 2 Concentration ratio F 1.70; Fe / TiO 2 0.28; solid content 21mg / L; stability 500.

[0027] (2) Preheating of lye: in the hydrolysis preparation tank, the temperature of sodium hydroxide solution is 50°C, the concentration is 8.2%, and the amount of lye is controlled to control the seed acid ratio F=0.35.

[0028] (3) Neutralization: within 1 minute, add the titanium sulfate solution to the alkali solution, and the reaction time is 80 minutes. After the reaction, the temperature of the seed crystal was 42°C.

[0029] ⑷Dilution: add water to dilute, control seed TiO 2 The concentration is 35.54g / L. After standing for 50 days, it can still be used as hydrolysis seed crystal...

Embodiment 2

[0031] (1) Titanium sulfate solution: hydrolyze the titanium sulfate solution according to the volume ratio of 0.5%, and the temperature of the titanium sulfate solution is 60°C. Titanium Sulfate Liquid TiO 2 Concentration 201.46g / L; Ti 3+ 1.89g / L (as TiO 2 count); effective acid and total TiO 2 Concentration ratio F 1.80; Fe / TiO 2 0.30; solid content 28mg / L; stability 550.

[0032] (2) Preheating of lye: in the hydrolysis preparation tank, the temperature of sodium hydroxide solution is 60°C, the concentration is 8.4%, and the amount of lye is controlled to control the seed acid ratio F=0.45.

[0033] (3) Neutralization: within 2 minutes, add the titanium sulfate solution to the alkali solution, and the reaction time is 70 minutes. After the reaction, the temperature of the seed crystal was 50°C.

[0034] ⑷Dilution: add water to dilute, control seed TiO 2 The concentration is 50.25g / L. After standing for 60 days, it can still be used as hydrolysis seed crystal.

Embodiment 3

[0036] ⑴Titanium sulfate liquid: according to the volume ratio of hydrolyzed titanium sulfate liquid 0.8%, the temperature of titanium sulfate liquid is 65 ℃. Titanium Sulfate Liquid TiO 2 Concentration 200.16g / L; Ti 3+ 2.5g / L (as TiO 2 count); effective acid and total TiO 2 Concentration ratio F 1.85; Fe / TiO 2 0.29; solid content 22mg / L; stability 550.

[0037] (2) Preheating of lye: in the hydrolysis preparation tank, the temperature of sodium hydroxide solution is 65°C, the concentration is 8.0%, and the amount of lye is controlled to control the seed acid ratio F=0.40.

[0038] (3) Neutralization: within 2 minutes, add the titanium sulfate solution to the alkali solution, and the reaction time is 60 minutes. After the reaction, the temperature of the seed crystal was 55°C.

[0039] ⑷Dilution: add water to dilute, control seed TiO2 The concentration is 53.18g / L. After standing for 47 days, it can still be used as hydrolysis seed crystal.