JPS61215222A - Production of solution of ferric polysulfate - Google Patents

Abstract

PURPOSE:To obtain a solution of ferric polysulfate having stable qualities by a short time reaction, by adding tri-iron tetroxide to an aqueous solution of sulfuric acid in a specific molar ratio, and reacting them while stirring. CONSTITUTION:Tri-iron tetroxide in an amount corresponding to = 3mols - <4mols sulfuric acid based on 1mol tri-iron tetroxide is dispersed into an aqueous solution of sulfuric acid while stirring. After being stirred for a while, the solution is allowed to stand, and undissolved tri-iron tetroxide is removed by filtration. By this method, a solution of ferric polysulfate is instantly obtained by a directly radically and harmlessly without causing oxidation. A production device can be miniaturized.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] This invention relates to a method for producing a polyferric sulfate solution by adding triiron tetroxide to an aqueous sulfuric acid solution.

[Conventional technology]

Conventionally, there is a method of producing a polyferric sulfate solution by adding sulfuric acid to a ferric sulfate solution and oxidizing it with air and an oxidizing agent, but this production method requires large-scale equipment, In addition, air oxidation requires a relatively long reaction time, and the ferric polysulfate solution produced by this production method has the problem of not being stable in quality.

[Problem that the invention seeks to solve]

Therefore, the method for producing a polyferric sulfate solution of the present invention was developed in order to solve the problems of the above-mentioned conventional method.
The purpose is to shorten reaction time, downsize equipment, and stabilize quality, as well as to provide a method for producing polyferric sulfate solution that is harmless and can be produced immediately. Means for Solving the Problems Therefore, the method for producing a polyferric sulfate solution of the present invention is as follows:
Add 3 moles or more of sulfuric acid per 1 mole of triiron tetroxide to a sulfuric acid aqueous solution.
Polymerization is achieved by adding triiron tetroxide in an amount equivalent to less than a mole and stirring.

[Effect]

As a result of the above measures, the oxidation reaction that produces ferrous sulfate from triiron tetroxide and sulfuric acid does not occur, and ferric polysulfate is directly produced by a radical reaction.

〔Example〕

Hereinafter, the configuration of the present invention will be explained according to examples.

40% sulfuric acid aqueous solution 1 in the reaction vessel! Adjust M and add 5000 g of triiron tetroxide in a dispersed manner while stirring. After stirring for a while, the solution is allowed to stand still, or a magnet is suspended in the solution, and undissolved triiron tetroxide is removed from the solution, producing a polyferric sulfate solution. Ru.

The triiron tetroxide used in this invention is also called magnetic iron oxide, and is naturally produced as magnetite, but in recent years it has been generated in large quantities by titanium manufacturers as a byproduct during titanium extraction. Since the uses of triiron tetroxide are narrowly limited, most of it is currently converted to red iron oxide or used again as a raw material for iron manufacturing, but this invention aims to effectively utilize this abundant by-product. It is something to be measured. Furthermore, according to many literatures, it is said that triiron tetroxide is soluble in hydrochloric acid but difficult to melt in sulfuric acid.
It was found that it dissolves well over a range of 5±5%.

In the above reaction process, 85% or more of triiron tetroxide is dissolved. Furthermore, by adding a small amount of sodium chlorate, the reaction proceeded rapidly, and more than 95% of the triiron tetroxide was dissolved, making it possible to obtain a brown viscous ferric polysulfate solution. In addition, in the above reaction process, in order to maintain the basic state and polymerize, at least 3 moles and less than 4 moles of sulfuric acid (FesO+ + (4-n
)H! LSOq) Requires a mixing ratio of 3≦n<4. Furthermore, in the above reaction, it is thought that by adding a small amount of sodium chlorate, this sodium chlorate acts as a reaction accelerator and causes a radical reaction.

As the reaction accelerator, in addition to sodium chlorate, oxidizing agents such as hydrogen peroxide and sodium perchlorate can be used.

By mixing triiron tetroxide and sulfuric acid, the molecular formula of triiron tetroxide is changed from FezO,y-FeO to Fe1Oa-Fe
O+ 4 HISOaz--Fe2(SotI)J+F
If it becomes e5O1+ 4820, the oxidizing agent required for Fe50 da is FezO3-FeO:NaCl0a:232
: 57.5, and when converted to the example, triiron tetroxide 5
1,239 g of sodium chlorate per 1,000 g, which required a large amount of oxidizing agent, but in reality it reached a saturated state at 30.5 g, and if more was added, chlorine gas was generated. Therefore, since the amount of ferrous sulfate that is thought to be generated in the reaction between triiron tetroxide and sulfuric acid is extremely small or nonexistent, the reaction itself is considered to be a radical reaction.

The precipitates and insoluble matter obtained as a result of the above-mentioned aging were analyzed by fluorescent X-ray method and powder X-ray diffraction method, and it was found that the main components were the same as the raw materials.

Next, the analysis results of the polyferric sulfate solution obtained in the above example are shown in the table below.

In the table, the amount of iron in the table was determined using atomic absorption method, the amount of sulfate ion was determined using the JIS 0102 gravimetric method, the specific gravity was determined using the floating balance method, and the viscosity was determined using an Ubbelohde viscosity needle. The heating residue was obtained by putting the sample solution Ag in an evaporating dish and heating it on a water bath for 10 hours, and then putting it in a dryer and heating it at 160° C. for 10 hours to dry it. After cooling this in a desiccator for 30 minutes, it was weighed and the loss on drying (Bg) was determined to yield the percentage of heating residue (Cg).

C (wt%) = B/Ax 100 [Effects of the Invention] Since the method for producing a polyferric sulfate solution of the present invention is configured as described above, the reaction time is shorter than that of the conventional production method. Not only is it possible to shorten the process, downsize equipment, and stabilize quality, but it is also harmless and allows immediate production of ferric polysulfate solution. The factory is equipped with its own agitator,
Not only can it produce a polyferric sulfate solution that meets usage conditions, but it can also produce a polyferric sulfate solution in pit areas that cannot be stored for a long time and can be used immediately, and has excellent effects. .

Claims (1)

[Claims] 1. Polyferric sulfate, which is polymerized by adding triiron tetroxide in an amount equivalent to 3 moles or more and less than 4 moles of sulfuric acid per 1 mole of triiron tetroxide to a sulfuric acid aqueous solution and stirring. Method of manufacturing the solution.