CN104445304A - Method for preparing basic magnesium carbonate by using combinative alkali system high-salt heavy-ash mother solution - Google Patents

Abstract

The invention discloses a method for preparing basic magnesium carbonate by using a combinative alkali system high-salt heavy-ash mother solution. The method comprises the following steps: (1) dissolving industrial magnesium chloride into a solution with the concentration of 1-1.45mol/L, heating to 80-90 DEG C, and filtering to remove insoluble substances; (2) heating a high-salt heavy-ash mother solution to 50-60 DEG C, keeping the temperature constant, and then filtering to remove calcium ion impurities; (3) adding the filtered high-salt heavy-ash mother solution into the filtered industrial magnesium chloride solution while stirring for fully reacting, and then keeping the temperature of the solution after reaction for 2-3 hours, wherein the molar volume ratio of the added amounts of the high-salt heavy-ash mother solution and the industrial magnesium chloride solution is 1.2-1.5; and (4) filtering a magma solution, washing by using deionized water at the same time, and drying at 120-130 DEG C to obtain a basic magnesium carbonate product. The magnesium oxide content of the basic magnesium carbonate prepared by the method disclosed by the invention is about 41% and can reach an industrial standard.

Description

A kind of method utilizing the heavy grey mother liquor of connection alkali system height salt to prepare magnesium basic carbonate

Technical field

The present invention relates to a kind of method preparing magnesium basic carbonate, especially a kind of method using the heavy grey mother liquor of connection alkali system height salt to prepare magnesium basic carbonate.

Background technology

Magnesium basic carbonate purposes widely, be mainly used in the industries such as rubber, enamel, plastics, paint, pharmacy, electronics, cable, be good siccative, wear-resisting and lagging material, be again prepare one of high-purity magnesium oxide simultaneously, have very large demand in China.Connection alkali system is produced in heavy grey process, and the chlorion in heavy grey mother liquor constantly accumulates, and when chloride ion content is greater than 60g/L usually, needs discharge unit mother liquor, maintains system balancing, guarantees to obtain qualified product.In the heavy grey mother liquor of high salt of discharge, main component is sodium carbonate and sodium-chlor, therefore utilize the heavy grey mother liquor of this high salt and magnesium chloride to carry out the preparation of magnesiumcarbonate, can the wasting of resources be reduced, reclaim the sodium carbonate in the heavy grey mother liquor of high salt, product magnesiumcarbonate can be obtained simultaneously, increase product value added.

The patent No. is 200510044626.3 patent discloses a kind of " cleaning production method of medicinal magnesiumcarbonate ", the method with the byproduct calcining furnace phlegma of salt-manufacturing waste liquor bittern and soda factory for raw material, magnesiumcarbonate preparation process comprises the following steps: (1) adds bittern in the reactor, and bittern is heated to 50-80 DEG C; (2) under agitation slowly phlegma is added, insulation reaction 1 hour; (3) after completion of the reaction, ageing 24 hours, filters, and uses deionized water wash to remove sulfate ion and chlorion; (4) at 90 DEG C-130 DEG C, magnesium basic carbonate is made in oven dry.Using the method to prepare magnesiumcarbonate uses bittern and phlegma reaction times and digestion time longer, and make the magnesiumcarbonate production cycle long, production efficiency is low.

The patent No. is 201010571934.2 patent discloses " a kind of method that urao prepares magnesium basic carbonate and high-purity magnesium oxide ", the method comprises the following steps: natural alkali lye is carried out thermolysis at 80-110 DEG C by (1), and the sodium bicarbonate of more than 50% is decomposed into sodium carbonate; (2) by magnesium chloride hexahydrate water dissolution, the magnesium chloride solution concentration after dissolving remains on 1.5-2mol/L, uses sand coarse aggregate ratio strainer to filter, obtains purified magnesium chloride solution; (3) purified magnesium chloride is put into enamel reaction still, be heated to 80-105 DEG C, add the trona solution in step (1), by solution ebuillition of heated, Magnesium hydrogen carbonate is resolved into magnesiumcarbonate, reaction 1-2 hour; (4) material in enamel reaction still is taken out, enter in van-type strainer and carry out solid-liquid separation, use hot water to wash, obtain water and magnesium basic carbonate 110-160 DEG C of drying.(5) water and magnesium basic carbonate are calcined 4-6 hour at 800-900 DEG C, can obtain high-purity magnesium oxide product, in product, content of magnesia is greater than 98%.The method needs to prepare Magnesium hydrogen carbonate, then obtains magnesiumcarbonate by Magnesium hydrogen carbonate decomposition, and this technical process is numerous and diverse, and consuming time more, and production cost is higher.

Summary of the invention

The object of the invention is to the deficiency overcoming prior art, provide a kind of production cost low, the heavy grey mother liquor of utilization connection alkali system height salt that quality product is high prepares the method for magnesium basic carbonate.

The present invention seeks to be achieved through the following technical solutions.

Utilize the heavy grey mother liquor of connection alkali system height salt to prepare a method for magnesium basic carbonate, it comprises the following steps:

(1) industrial hex-ammoniate be dissolved as the solution of 1-1.45mol/L and be heated to 80-90 DEG C, crossing and filter insolubles;

(2) get the heavy grey mother liquor of high salt and be heated to 50 DEG C-60 DEG C, keep constant temperature, then cross and filter calcium ion impurities;

(3) the heavy grey mother liquor of high salt after filtering under agitation is added to filter in postindustrial magnesium chloride solution make both fully reactions, then solution insulation 2-3 hour after reacting, the heavy grey mother liquor of high salt is 1.2-1.5 with the molecular volume ratio of the add-on of industrial chlorinations magnesium solution;

(4) magma is filtered, use deionized water wash simultaneously, 120-130 DEG C of drying, obtain basic carbonate magnesium products.

In the magnesium basic carbonate using the method to prepare, content of magnesia is about 41%, can reach industry standard.The present invention has the following advantages: use the present invention to carry out the preparation of magnesium basic carbonate, production technique is simple, with short production cycle, the heavy grey mother liquor of high salt of connection alkali system discharge can be used simultaneously cost-saved as raw material, improve product economy benefit.

Embodiment

Below in conjunction with specific embodiment, the present invention is described in detail.

A kind of method utilizing the heavy grey mother liquor of connection alkali system height salt to prepare magnesium basic carbonate of the present invention, it comprises the following steps: industrial hex-ammoniate is dissolved as the solution of 1-1.45mol/L and is heated to 80-90 DEG C by (1), crosses and filters insolubles; (2) get the heavy grey mother liquor of high salt and be heated to 50 DEG C-60 DEG C, keep constant temperature, then cross and filter calcium ion impurities; About constant temperature time can remain on half an hour; (3) the heavy grey mother liquor of high salt after filtering under agitation is added to filter in postindustrial magnesium chloride solution make both fully reactions, then solution insulation 2-3 hour after reacting, the heavy grey mother liquor of high salt is 1.2-1.5 with the molecular volume ratio of the add-on of industrial chlorinations magnesium solution; (4) magma is filtered, use deionized water wash simultaneously, 120-130 DEG C of drying, obtain basic carbonate magnesium products.

Embodiment 1

(1) industrial hex-ammoniate be dissolved as the solution of 1mol/L and be heated to 80 DEG C, crossing and filter insolubles; (2) get the heavy grey mother liquor of high salt and be heated to 50 DEG C, keep constant temperature half an hour, then cross and filter calcium ion impurities; (3) the heavy grey mother liquor of high salt after filtering under agitation is added to filter in postindustrial magnesium chloride solution make both fully reactions, then solution after reaction is incubated 2 hours, the heavy grey mother liquor of high salt is 1.2 with the molecular volume ratio of the add-on of industrial chlorinations magnesium solution; (4) magma is filtered, use deionized water wash simultaneously, 120 DEG C of dryings, obtain basic carbonate magnesium products.

After testing: in the product obtained, content of magnesia is 41.2%.

Embodiment 2

(1) industrial hex-ammoniate be dissolved as the solution of 1.2mol/L and be heated to 90 DEG C, crossing and filter insolubles; (2) get the heavy grey mother liquor of high salt and be heated to 60 DEG C, keep constant temperature 40 minutes, then cross and filter calcium ion impurities; (3) the heavy grey mother liquor of high salt after filtering under agitation is added to filter in postindustrial magnesium chloride solution make both fully reactions, then solution after reaction is incubated 3 hours, the heavy grey mother liquor of high salt is 1.5 with the molecular volume ratio of the add-on of industrial chlorinations magnesium solution; (4) magma is filtered, use deionized water wash simultaneously, 130 DEG C of dryings, obtain basic carbonate magnesium products.

After testing: in the product obtained, magnesian content is 41%.

Embodiment 3

(1) industrial hex-ammoniate be dissolved as the solution of 1.45mol/L and be heated to 85 DEG C, crossing and filter insolubles; (2) get the heavy grey mother liquor of high salt and be heated to 55 DEG C, keep constant temperature 28 minutes, then cross and filter calcium ion impurities; (3) the heavy grey mother liquor of high salt after filtering under agitation is added to filter in postindustrial magnesium chloride solution make both fully reactions, then solution after reaction is incubated 2.5 hours, the heavy grey mother liquor of high salt is 1.3 with the molecular volume ratio of the add-on of industrial chlorinations magnesium solution; (4) magma is filtered, use deionized water wash simultaneously, 125 DEG C of dryings, obtain basic carbonate magnesium products.

After testing: in the product obtained, magnesian content is 41%.

Claims (1)

1. utilize the heavy grey mother liquor of connection alkali system height salt to prepare a method for magnesium basic carbonate, it is characterized in that it comprises the following steps:

(1) industrial hex-ammoniate be dissolved as the solution of 1-1.45mol/L and be heated to 80-90 DEG C, crossing and filter insolubles;

(2) get the heavy grey mother liquor of high salt and be heated to 50 DEG C-60 DEG C, keep constant temperature, then cross and filter calcium ion impurities;

(3) the heavy grey mother liquor of high salt after filtering under agitation is added to filter in postindustrial magnesium chloride solution make both fully reactions, then solution insulation 2-3 hour after reacting, the heavy grey mother liquor of high salt is 1.2-1.5 with the molecular volume ratio of the add-on of industrial chlorinations magnesium solution;

(4) magma is filtered, use deionized water wash simultaneously, 120-130 DEG C of drying, obtain basic carbonate magnesium products.