CN1312224A

CN1312224A - Liquid phase synthesis process of producing nanometer iron oxide red

Info

Publication number: CN1312224A
Application number: CN 00129970
Authority: CN
Inventors: 童忠良
Original assignee: Individual
Current assignee: Individual
Priority date: 2000-10-16
Filing date: 2000-10-16
Publication date: 2001-09-12

Abstract

The production method of nanometer iron oxide red is characterized by utilizing hydrolysis of Fe(3+) salt and Fe salt containing PO4(3-), adopting microwave heating preparation process and adopting Fe(2+) air oxidation to form FeOH firstly, then in the presence of phase-inversion catalyst quickly and directly converting it into iron red particles for 3-4 min. The initial concentration of the reaction produce can be up to 1.8 mol, and the final iron red particle size can be controlled by changing reaction condition, and the spherical particular iron oxide red white powder with about 20-50 nm and 50-100 nm can be obtained.

Description

Production method for liquid-phase synthesis of nano iron oxide red powder

The invention relates to a method for producing iron oxide red, in particular to a preparation technology for producing nano iron oxide red powder by a liquid phase method, which is characterized by adopting a new process for synthesizing the iron oxide red by one step by the liquid phase method.

The nano iron oxide red powder is widely applied to the fields of catalysis, functional ceramics, magnetic materials, transparent pigments and the like, and along with the development and application of high-technology products, the nano iron oxide red powder not only requires the size of oxidized particles to be micronized, but also continuously improves the requirement on the uniformity of the particles. At present, in a plurality of nano-scale iron oxide red powder preparation processes, the cost of a hydrothermal method is relatively low to be 1.0-1.2 ten thousand yuan/ton, and other preparation methods cannot be industriallyproduced due to high cost.

The starting technology for producing the manganese-zinc soft magnet by oxidation generally adopts a chemical method to produce an iron oxide red raw material, partially adopts a raw material produced by a precipitation method, adopts a Ruhl method to produce the iron oxide red raw material to manufacture manganese-zinc ferrite, only starts in recent years, and basically adopts iron oxide produced by Bao steel. Recently, Bao steels have begun to produce manganese-zinc ferrite pre-sinter as well as iron oxide by the Roux process. Most of the iron oxide red is produced by a batch method, and the process can also adopt the batch method, but because the influence factors of liquid phase conversion are less, the size and the appearance of the product are difficult to control to be completely consistent. Due to the fe (oh) used in the process. The gel can be quickly converted into iron oxide red in the presence of phase-conversion catalyst, so that it can adopt continuous reactor to make production, and can not only solve the problem of product consistency, but also can greatly raise production capacity.

The invention aims to provide a method for producing nano-scale iron oxide red powder, which has the advantages of simple equipment, short process flow, less investment and low cost.

The production method of the iron oxide red powder provided by the invention adopts a new process for synthesizing the nano iron oxide red in one step by a liquid phase method.

The liquid phase gel method is that inorganic salt is used as raw material, hydrolysis is carried out in medium, chemical reaction leads the solution to be gelated to obtain gel, and the gel is heated, dried and calcined to obtain the product. The powder obtained by the method is uniformly distributed, and has good dispersibility and high purity. Low calcining temperature, easy control of reaction, less side reaction and high efficiencyThe process is simple to operate. The gel method reaction mechanism is as follows:

the process flow is shown in the attached drawing.

The product is illustrated by the examples below: (1) ferric salt solution is utilized to be directly converted into iron oxide red particles rapidly (3-4min) within 105 ℃ in the presence of trace phase conversion catalyst. (2) The initial concentration of the reactant can reach 1.8mol^-13.2 times of that of a hydrothermal method and more than 12 times of that of a forced hydrolysis method. (3) By changing the reaction conditions, the size of the final iron oxide red particles can be artificially controlled, and spherical particles with different particle sizes of about 20-50nm,50-100nm and the like can be prepared. (4) Because high temperature and high pressure are not needed and the phase conversion rate is rapid, the investment of reaction equipment and energy consumption are greatly reduced. (5) Because the process has no waste gas pollution, the reaction mother liquor only contains ammonium sulfate, and is faintly acid, and because the reactant concentration is high, the concentrated mother liquor can be recovered to prepare the compound fertilizer.

The main raw materials used in the above embodiment are low-carbon iron sheet leftovers of a sugar and porcelain factory and ferrous sulfate which is a byproduct of a titanium dioxide factory, and the acid washing liquid of a steel factory is used, and the value of innovation is realized by utilizing thewaste materials.

Claims

1. The invention relates to a production method of nano iron oxide red, in particular to a preparation process of nano uniform iron oxide red powder, which is characterized by adopting a liquid-phase rapid catalytic conversion method.

2. The liquid phase rapid catalytic conversion process of claim 1, wherein a solution of ferric salt is rapidly converted (3-4min) to iron red particles at 105 ℃ for 3-4min in the presence of a trace amount of phase conversion catalyst.

3. The liquid phase rapid catalytic conversion process of claims 1 and 2, further comprising a concentration of reactants up to 1.8mol^-1The size of the final iron oxide red particles can be artificially controlled to be about 20-50nm by changing the reaction conditions, and the sizes of the final iron oxide red particles are 50-100 nm.