CN102502876A

CN102502876A - Method for synthesizing iron oxide black by oxidizing sodium nitrate

Info

Publication number: CN102502876A
Application number: CN2011103052447A
Authority: CN
Inventors: 孙晓庆; 崔前志
Original assignee: ANHUI MINGZHU PIGMENT TECHNOLOGY Co Ltd
Current assignee: ANHUI MINGZHU PIGMENT TECHNOLOGY Co Ltd
Priority date: 2011-10-11
Filing date: 2011-10-11
Publication date: 2012-06-20

Abstract

The invention relates to a method for synthesizing iron oxide black by oxidizing sodium nitrate, comprising the following steps: mixing 30-45% liquid caustic soda with 38-42% ferrous sulfate solution according to the mass ratio of 1:1.2 in a reactor, controlling the temperature at 50-60 DEG C, and adjusting the pH value of slurry to 7.2-7.5 to obtain a mixed slurry; adding water to dilute the mixed slurry until the content of slid is 8-12%, introducing steam to heat the slurry to 92-98 DEG C, stop heating by the steam, keeping the temperature, adding the sodium nitrate into the reactor by three times according to the mass ratio of FeSO4 to the sodium nitrate ratio of 1:0.023, continuously sampling, analyzing and detecting, stopping reaction after the tinting strength and the color shade reach the production indexes, discharging, carrying out filter pressing by using a plate frame, washing, drying and crushing to obtain the product. The product which is the iron oxide black synthesized by adopting the method has high purity, low tinting strength, and stable hue, and particularly, the tinting strength of the iron oxide black is only 50% of that of the common iron oxide black.

Description

The synthetic iron black method of a kind of SODIUMNITRATE oxidation

Technical field

The present invention relates to a kind of working method of iron oxide black, exactly is the synthetic iron black method of a kind of SODIUMNITRATE oxidation.

Background technology

Iron black: molecular formula Fe ₃O ₄, the chemical name Z 250 belongs to spinel type; Have saturated blue black light black, specific density is 4.73, and good tinting strength is arranged; Very stable to light and atmospheric effect, the iron oxide black also is used for building trade cement because of strong coloring force, good being applied to of light fastness outside the coating industry system device lacquer.But development and progress along with society; The particularly development of coating and building material industry, increasingly high to the application performance requirement of material, also more and more to the requirement of iron oxide black pigment kind; The product iron oxide black that the SODIUMNITRATE oxidation style is given birth to; Have the purity height, the characteristics that intensity is low can fulfilling medicinal and the demand that is mixed of pigment.

Summary of the invention

It is high to the purpose of this invention is to provide a kind of product purity, the synthetic iron black method of the SODIUMNITRATE oxidation that tinting strength is low, form and aspect are stable.

Technical scheme of the present invention is:

The synthetic iron black method of a kind of SODIUMNITRATE oxidation is characterized in that: may further comprise the steps:

(1), in reaction kettle, be the liquid caustic soda of 30-45%, copperas solution that concentration is 38-42% by mass ratio be 1: 1.2～1.5 to mix with concentration, controlled temperature is 50-60 ℃, the pH value of regulating slip between 7.2-7.5, mixed slurry;

(2), thin up mixed slurry to solid content is 8-12%, feeds steam slurry temperature is increased to 92-98 ℃, stops steam heating, keeps this temperature, presses FeSO ₄With the mass ratio of SODIUMNITRATE be 1: 0.023～0.028; Divide and at a distance from 28-32 minute SODIUMNITRATE is dropped in the reaction kettle for three times at every turn; Constantly sampling analysis detects, and power to be colored and coloured light reach discharging behind the stopped reaction after the productive capacity, after filter press, washing, oven dry, fragmentation, promptly get product.

The method that described SODIUMNITRATE oxidation is synthetic iron black is characterized in that: described copperas solution uses method for hydrolysis to remove copperas solution water adjusting concentration behind the titanium impurity and gets after as 38-42%, and its temperature is controlled at 35-45 ℃; Described SODIUMNITRATE is concentration greater than 99% technical grade SODIUMNITRATE.

Principle equation of the present invention:

FeSO ₄+2NaOH→Fe(OH) ₂↓+Na ₂SO ₄

8Fe(OH) ₂+NaNO ₃+6H ₂O→8Fe(OH) ₃↓+NaOH+NH ₃

Fe(OH) ₂+2Fe(OH) ₃→Fe ₃O ₄↓+4H ₂O

Beneficial effect of the present invention is:

Institute of the present invention synthetic iron oxide black is superior to common iron oxide black product on physical and chemical index, on pigment performance different with in common iron black product, product purity is high, tinting strength is low, form and aspect are stable, particularly tinting strength is merely 50% of common tinting strength.

Embodiment

Technical scheme of the present invention is:

(1), in reaction kettle, be that 30% liquid caustic soda, concentration be 40% copperas solution by mass ratio are to mix at 1: 1.2 with concentration, controlled temperature is 50-60 ℃, the pH value of regulating slip between 7.2-7.5, mixed slurry;

(2), thin up mixed slurry to solid content is 10%, feeds steam slurry temperature is increased to 95 ℃, stops steam heating, keeps this temperature, presses FeSO ₄With the mass ratio of SODIUMNITRATE be 1: 0.0230; Whenever at a distance from 30 minutes branches three times SODIUMNITRATE is dropped in the reaction kettle; Constantly sampling analysis detects, and power to be colored and coloured light reach discharging behind the stopped reaction after the productive capacity, after filter press, washing, oven dry, fragmentation, promptly get product.

The method that described SODIUMNITRATE oxidation is synthetic iron black is characterized in that: described copperas solution uses method for hydrolysis to remove copperas solution water adjusting concentration behind the titanium impurity and gets after as 38-42%, and its temperature is controlled at 40 ℃; Described SODIUMNITRATE is concentration greater than 99% technical grade SODIUMNITRATE.

Each item index contrast of the present invention and common iron oxide black:

Through relatively can knowing that institute of the present invention synthetic iron oxide black is superior to common iron oxide black product on physical and chemical index, on pigment performance different be merely 50% of common tinting strength in common iron black product, particularly tinting strength.

Claims

1. iron black method is synthesized in a SODIUMNITRATE oxidation, it is characterized in that: may further comprise the steps:

(1), in reaction kettle, be that the liquid caustic soda of 30-45%, copperas solution that concentration is 38-42% are that mix 1:1.2～1.5 by mass ratio with concentration, controlled temperature is 50-60 ℃, the pH value of regulating slip between 7.2-7.5, mixed slurry;

(2), thin up mixed slurry to solid content is 8-12%, feeds steam slurry temperature is increased to 92-98 ℃, stops steam heating, keeps this temperature, presses FeSO ₄With the mass ratio of SODIUMNITRATE be 1:0.023～0.028; Divide and at a distance from 28-32 minute SODIUMNITRATE is dropped in the reaction kettle for three times at every turn; Constantly sampling analysis detects, and power to be colored and coloured light reach discharging behind the stopped reaction after the productive capacity, after filter press, washing, oven dry, fragmentation, promptly get product.

2. the synthetic iron black method of SODIUMNITRATE oxidation according to claim 1; It is characterized in that: described copperas solution uses method for hydrolysis to remove copperas solution water behind the titanium impurity and regulates concentration and get after as 38-42%, and its temperature is controlled at 35-45 ℃; Described SODIUMNITRATE is concentration greater than 99% technical grade SODIUMNITRATE.