CN103318971B - Liquid-phase low-heavy-metal iron oxide brown - Google Patents

Abstract

The invention relates to liquid-phase low-heavy-metal iron oxide brown. A method for preparing the liquid-phase low-heavy-metal iron oxide brown comprises the following steps of: (a) adding a ferrous sulfate solution into a pressure reaction kettle, and introducing nitrogen gas into the reaction kettle; (b) closing all valves of the reaction kettle, and heating the reaction kettle while stirring; (c) injecting alkali liquor, controlling the PH to be 6.8-7.3 at the pressure and temperature of the moment, stirring and continuously heating, controlling the heating rate to be 2-6 DEG C per minute, and carrying out heat preservation when the temperature is heated to 90-120 DEG C; and (d) after the heat preservation is ended, quickly cooling to normal temperature by using cold circulating water, opening the valves, rinsing brown slurry, carrying out pressure filtration, drying and crushing, thereby obtaining the iron oxide brown. According to the liquid-phase low-heavy-metal iron oxide brown, due to the adoption of the technical scheme, the process is simple, the production cycle is short, and the finished product has the advantages of good coloring power, temperature resistance, environmental friendliness, low heavy metal and the like.

Description

A kind of Liquid-phase low-heavy-metal iron oxide brown

Technical field

The present invention relates to a kind of preparation method of iron oxide brown.

Background technology

The molecular formula of iron oxide brown is (Fe2O3+FeO) nH ₂o, he is a kind of brown ceramic powder, water insoluble, alcohol, and ether, is dissolved in strong acid, simultaneously tinting strength and opacifying power very high, photostabilization, alkali resistance is good, without water permeability and oil impregnate.Its form and aspect are divided into along with the difference of technique: reddish brown, yellowish-brown, black palm fibre etc.It is widely used in paint, ink, plastics, the goods such as shoe powder painted, and coating, rubber, building painted.

Traditional cologne earth passes through, iron black, iron oxide yellow, iron oxide red three kinds of pigment physics blendings, unstable product quality, and form and aspect are not enough.And three primary colors used are iron black, iron oxide yellow, iron oxide red is all that liquid phase reaction is obtained, so cannot ensure heavy metal content.So the quality of the iron oxide brown using this technique to synthesize is higher than the iron oxide brown that blending obtains.

The process cycle of the cologne earth disclosed in Chinese patent CN-102502861 A is long, and technique is also more complicated.The reaction time that technology disclosed in this patent relates to is shorter, is the process cycle half of the cologne earth disclosed in Chinese patent CN-102502861 A.And this technique directly synthesizes cologne earth, comparatively simply.

Summary of the invention

In order to realize above-mentioned object, object of the present invention provides a kind of Liquid-phase low-heavy-metal iron oxide brown, and the iron oxide brown that the method is produced is reddish-brown, possesses good tinting strength, temperature tolerance, the advantages such as environmental protection low heavy metal.

In order to realize above-mentioned object, present invention employs following technical scheme:

A kind of Liquid-phase low-heavy-metal iron oxide brown, the preparation method of this iron oxide brown comprises the following steps:

A) copperas solution being 400g/L by the concentration after purification adds in pressure reaction still, in reactor, pass into nitrogen, drives away surplus air in reactor, and fills reactor remaining space;

B) all valves of off-response still, heat reactor, open stirring simultaneously, are controlled by temperature of reaction kettle at 90 DEG C-120 DEG C;

C) alkali lye of same concentrations is squeezed into pressure pump, under pressure and temperature condition at this moment, pH value controls at 6.8-7.3, opening to stir and continue to heat up controls at 90 DEG C-120 DEG C by temperature, heat-up rate controls at 2-6 DEG C of per minute, be incubated when temperature rises to 90 DEG C-120 DEG C, soaking time controls at 2-5 hour;

D) be incubated end cool circulation water and carry out being quickly cooled to normal temperature, open valve, rinsing is carried out to brown slurry, press filtration, dry, pulverize, namely obtain iron oxide brown.

As preferably: the preparation of described copperas solution comprises the following steps:

A) obtain ferrous water-soluble for solid sulphuric acid the copperas solution that concentration is 700g/L;

B) add the vitriol oil of 98%, the add-on of the vitriol oil is 1.6% of ferrous sulfate quality;

C) add iron plate and lead to steam and maintain the temperature at about 60 DEG C, maintain 8 hours;

D) take out liquid phase, be diluted to 400g/L;

E) add flocculation agent, flocculant usage is 0.007% of iron vitriol;

F) stir 10 minutes, leave standstill 6 hours, get upper liquid and be POV ferrous iron solution.

The present invention is owing to adopting technique scheme, and technique is simple, with short production cycle, and finished product possesses good tinting strength, temperature tolerance, the advantages such as environmental protection low heavy metal.

Embodiment

One, the making step of copperas solution is as follows:

First obtain ferrous water-soluble for solid sulphuric acid the copperas solution that concentration is 700g/L, add the vitriol oil of 98%, the add-on of the vitriol oil is 1.6% of ferrous sulfate quality, adds iron plate and lead to steam to maintain the temperature at about 60 DEG C, maintain 8 hours, take out liquid phase, be diluted to 400g/L, add flocculation agent, flocculant usage is 0.007% of iron vitriol, stir 10 minutes, leave standstill 6 hours, get upper liquid and be the POV ferrous iron solution that concentration is 400g/L.

Two, the making step of Liquid-phase low-heavy-metal iron oxide brown is as follows:

Measure and add in pressure reaction still by the copperas solution 2000ml of purifying treatment, in reactor, pass into nitrogen, drive away surplus air in reactor, and fill reactor remaining space.The all valves of off-response still, heat reactor, open stirring simultaneously.

Temperature of reaction kettle is controlled at 120 DEG C, certain volume is squeezed into pressure pump, same concentrations is the alkali lye of 40%, now under pressure and temperature condition, PH is 7.2, opens to stir and continue to heat up to control at 120 DEG C by temperature, and heat-up rate controls at 2.5 DEG C of per minutes, be incubated when temperature rises to 120 DEG C, soaking time controls at 2-5 hour.

Insulation end cool circulation water carries out being quickly cooled to normal temperature, closes and stirs, open valve, carry out rinsing, press filtration to brown slurry, dry, pulverize, namely obtain low heavy metal iron oxide brown.

The technical indicator of the product that this technique obtains is as follows:

Technological project	Salable product	Measured result
			Iron level is [with Fe 2O 3(105 DEG C of oven dry) represents, %], >=	96.0	97.5
105 DEG C of volatile matters, %	1.0	0.8
			The water solubles (hot extraction process), %	0.5	0.34
Screenings (45 μm), %	0.3	0.14
			Aqeous suspension pH value	5.0-7.0	5.25
Oil number, g/100g	15-25	19.8
			Arsenic (As), mg/kg≤	1.0	0.493
Chromium (Cr), mg/kg≤	45.0	26.055
			Mercury (Hg) mg/kg≤	1.0	0.083
Nickel (Ni) mg/kg≤	30.0	17.542
			Plumbous (Pb), mg/kg≤	10.0	8.388

Colour index is as follows:

L	A	B
			25.86	6.79	4.75

Claims (1)

1. a Liquid-phase low-heavy-metal iron oxide brown, is characterized in that the preparation method of this iron oxide brown comprises the following steps:

A) copperas solution being 400g/L by the concentration after purification adds in pressure reaction still, in reactor, pass into nitrogen, drives away surplus air in reactor, and fills reactor remaining space;

B) all valves of off-response still, heat reactor, open stirring simultaneously, are controlled by temperature of reaction kettle at 90 DEG C-120 DEG C;

C) alkali lye of same concentrations is squeezed into pressure pump, under pressure and temperature condition at this moment, pH value controls at 6.8-7.3, opening to stir and continue to heat up controls at 90 DEG C-120 DEG C by temperature, heat-up rate controls at 2-6 DEG C of per minute, be incubated when temperature rises to 90 DEG C-120 DEG C, soaking time controls at 2-5 hour;

D) be incubated end cool circulation water and carry out being quickly cooled to normal temperature, open valve, rinsing is carried out to brown slurry, press filtration, dry, pulverize, namely obtain iron oxide brown.