阅读说明：本技术 一种由电石渣制备规整立方形轻质碳酸钙的方法 (Method for preparing regular cubic light calcium carbonate from carbide slag ) 是由 杨保俊 邵宗奇 杜正云 王百年 陈小龙 齐国祥 于 2019-12-11 设计创作，主要内容包括：本发明公开了一种由电石渣制备规整立方形轻质碳酸钙的方法,是以电石渣为原料,以NH<Sub>4</Sub>Cl溶液浸提电石渣中的钙离子,然后在电石渣浸提液中加入晶型控制剂,随后滴加(NH<Sub>4</Sub>)HCO<Sub>3</Sub>溶液,反应后过滤碳化液,所得滤饼经洗涤、干燥后得立方形轻质CaCO<Sub>3</Sub>样品。本发明以电石渣为原料制备高品质CaCO<Sub>3</Sub>产品,是电石渣的高附加值综合利用；此外,本发明采用较高Ca<Sup>+</Sup>浓度的电石渣浸取液溶液制备立方形CaCO<Sub>3</Sub>,生产效率高,同时具有工艺条件温和、设备要求低、晶型控制剂价廉易得、绿色环保等多重优点。(The invention discloses a method for preparing regular cubic light calcium carbonate from carbide slag, which takes carbide slag as raw material and NH 4 The Cl solution is used for leaching calcium ions in the carbide slag, then a crystal form control agent is added into the carbide slag leaching solution, and then (NH) is dripped 4 )HCO 3 The solution is reacted and then carbonized liquid is filtered, and the obtained filter cake is washed and dried to obtain cubic light CaCO 3 And (3) sampling. The invention takes the carbide slag as the raw material to prepare the high-quality CaCO 3 The product is high value-added comprehensive utilization of the carbide slag; in addition, the invention adopts higher Ca + Preparation of cubic CaCO from carbide slag leaching solution with concentration 3 The method has the advantages of high production efficiency, mild process conditions, low equipment requirements, cheap and easily available crystal form control agents, environmental protection and the like.)

1. A method for preparing regular cubic light calcium carbonate from carbide slag is characterized by comprising the following steps:

carbide slag is used as raw material, NH is used ₄The Cl solution is used for leaching calcium ions in the carbide slag, then a crystal form control agent is added into the carbide slag leaching solution, and then (NH) is dripped ₄)HCO ₃The solution is reacted and then carbonized liquid is filtered, and the obtained filter cake is washed and dried to obtain cubic light CaCO ₃And (3) sampling.

2. The method according to claim 1, characterized by comprising the steps of:

step 1: taking and measuring NH ₄Adding Cl into 500mL of deionized water, adding the carbide slag dried at 110 ℃, reacting for 1h at room temperature, and filtering to remove solid impurities in the reaction solution to obtain a certain amount of Ca ²⁺Carbide slag leaching liquor with concentration;

step 2: transferring a certain volume of the carbide slag leaching solution prepared in the step 1, and diluting the carbide slag leaching solution with deionized water to obtain the required Ca ²⁺CaCl of concentration ₂A solution; then adding a crystal form control agent according to a certain mass fraction, stirring and mixing uniformly under a certain temperature condition, and then dropwise adding a certain amount of (NH) under stirring ₄)HCO ₃Timing the solution, reacting and aging for 10-40 min to obtain a carbonized liquid, performing solid-liquid separation on the carbonized liquid, washing and drying the obtained filter cake to obtain cubic CaCO ₃And (3) sampling.

3. The method of claim 2, wherein:

in step 1, carbide slag and NH ₄The mass ratio of Cl is 1: 0.8.

4. The method of claim 2, wherein:

in the step 2, the crystal form control agent is one of magnesium hydroxide, sodium polyacrylate or dodecyl trimethyl ammonium bromide, and the addition amount is CaCO ₃3-6% of theoretical yield.

5. The method of claim 2, wherein:

in step 2, the resulting CaCl is diluted with deionized water ₂Ca in solution ²⁺The concentration is 0.3 to 0.8 mol.L ^-1。

6. The method of claim 2, wherein:

in step 2, CaCl ₂And (NH) ₄)HCO ₃In the precipitation reaction, CaCl ₂And (NH) ₄)HCO ₃The molar ratio of (A) to (B) is 1:0.5 to 1: 1.5.

7. The method of claim 2, wherein:

in step 2, diluting the obtained CaCl ₂Adding a crystal form control agent into the solution, uniformly mixing, and stirring and dropwise adding (NH) at the temperature of 25-50 DEG C ₄)HCO ₃Reacting and aging the solution for 10-40 min, and then carrying out solid-liquid separation to obtain a filtrate NH ₄Evaporating, concentrating and crystallizing the Cl solution to obtain NH ₄A Cl sample; washing and drying the obtained filter cake to obtain cubic CaCO ₃And (3) sampling.

8. The method of any one of claims 1-7, wherein:

the prepared regular cubic light CaCO ₃Is pure-phase calcite type, and has an average particle size of 3-5 μm.

Technical Field

The invention relates to a refined comprehensive utilization technology of carbide slag, in particular to a method for preparing regular cubic light calcium carbonate from carbide slag ²⁺Preparing cubic light CaCO by carbonate double decomposition precipitation method under the action of crystal form control agent ₃。

Background

Calcium carbonate is mainly classified into calcite, vaterite and aragonite types according to the crystal type. The shapes of the material include cubic, spherical, needle-shaped, spindle-shaped, sheet-shaped, diamond-shaped and the like. Cubic CaCO ₃Generally existing in the most stable calcite crystal form, the cubic CaCO prepared by the invention ₃Namely of the calcite type CaCO ₃. Cubic CaCO ₃It can be used as filler added into plastics, rubber and paper, and can raise the mechanical performance of base material, effectively improve the flowability and processing property of system and can raise the surface smoothness and filling property of product. In addition, CaCO in the form of cubes ₃The filler has better toughening effect on the matrix. Because of its more stable performance, it has become a more widely used CaCO ₃The type of product.

China is a world with calcium carbonate resources and a large number of producing countries. At present, the light CaCO in China ₃The total production is second only in the united states, and second in the world, the production has reached 400 ten thousand tons/year, but precipitated calcium carbonate with some technological added value only accounts for 7.7%, with varieties with high added value less than 0.5% of the total production. [ Korean Xiushan, China light calcium carbonate application and development [ J ]]The non-metallic mineral industries of china pilot 2004(6).]With the continuous improvement of the quality requirements of the products in the industries of rubber, plastics, paper making, paint, ink and the like in China, the demand of light calcium carbonate is increased day by day, so that CaCO is developed and perfected ₃The production process will have sufficient market demand for a considerable period of time in the future.

The carbide slag is industrial solid waste produced in the process of producing acetylene by calcium carbide, and the main component of the carbide slag is Ca (Ca:)OH) ₂. The accumulated stacking amount of the carbide slag in China exceeds billion tons, and most enterprises adopt a sand burying or open air stacking mode to dispose the carbide slag. The hazards caused by the accumulation of such a large amount of carbide slag are: (1) occupies a large amount of land resources. (2) Salinization of land and pollution of underground water source. (3) Toxic and harmful substances (such as H) generated during hydrolysis of calcium carbide ₂S、PH ₃、C ₂H ₂Etc.), seriously endangering the surrounding environment and the living health of residents. The Ministry of industry and communications released' Industrial Green development plan (2016-. Therefore, comprehensive utilization of resources is urgently needed.

At present, the carbide slag is mainly used for preparing building materials, treating acid waste gas and waste water, and raw materials of chemical products, and the like, and specifically comprises the following components:

(1) production of light brick

The carbide slag and the fly ash are used as raw materials, and the light brick with a certain specification is prepared by a series of working procedures such as pressing and the like after the carbide slag and the fly ash are mixed. The carbide slag can be used for producing putty for building indoor after being treated by a special process, and is convenient for industrial production. [ Sandalwood star, fly ash and carbide slag for producing autoclaved foam concrete building blocks [ D ]. Hebei science and technology university, 2019]

(2) Cement made by replacing limestone

The carbide slag is modified and then used for replacing natural gypsum to prepare cement. The process is that the raw materials of carbide slag, iron powder, clay, cinder, ore and silica are ground and mixed to prepare water-containing raw material, then the raw material is calcined to prepare clinker, and then the clinker is mixed with treated gypsum and ground to obtain the cement product. [ Lihabo. Cement clinker production line by carbide slag applying electric dust collector research [ A ] China silicate society environmental protection academic annual meeting argument [ C ]: China silicate society, 2012:5 ]

(3) Treating acidic waste gas and waste water

After mixing the carbide slag with water, the OH of the carbide slag ^-Can neutralize acid substances, and some heavy metal ions in the wastewater can generate hydroxide precipitates under the condition of proper pH value, thereby reducing the content of heavy metals and treating the acid wastewater. In addition, the flocculant can be used as a coagulant for treating papermaking wastewater and coal washing wastewater, so that the wastewater reaches the discharge standard. [ Wangli, Experimental study on solidification of sludge from municipal sewage plant by using phosphogypsum, fly ash and carbide slag [ D ]]University of Chongqing, 2012.]

(4) Production of soda ash and potassium chlorate

In the industry of preparing soda by ammonia-soda process, lime milk is prepared by using carbide slag to replace quicklime for emulsification reaction, and then the lime milk and NH are mixed ₄Cl to form ammonia, and then distilling to obtain NH ₃Recycling and reducing the cost. [ comprehensive utilization and analysis of carbide slag and fly ash in Lehu, Liu vegetarian plum, Liu Tibet and chlor-alkali enterprises [ J ]]Inner Mongolia petrochemical 2015,41(08):49-51.]

(5) Preparation of CaCO from carbide slag ₃

At present, the carbide slag is prepared into cubic light CaCO ₃In the report, the phase transfer method is mostly adopted to extract calcium element in carbide slag, and then cubic light CaCO meeting certain index requirements is synthesized ₃Producing a product; in addition, there are also reports of studies using the calcination method. Compared with the traditional calcining method, the phase transfer method can realize Ca under mild conditions ²⁺The extraction of (2) greatly reduces the energy consumption of production. [ Geli Bo, research on technological conditions for preparing nano calcium carbonate from carbide slag [ D]The university of fertilizer industry, 2016.]

Although the resource utilization of the carbide slag is widely developed, the comprehensive utilization rate is low, and the carbide slag is mostly utilized with low added value. If the carbide slag is used as a raw material, products such as light calcium carbonate with higher added value and the like can be developed, so that the method has considerable economic benefit. Therefore, it is very important to develop a novel and simple process method for preparing light calcium carbonate with high added value by using the carbide slag as a raw material.

Disclosure of Invention

The invention proposesMethod for preparing regular cubic light calcium carbonate from carbide slag, namely preparing high-quality CaCO from carbide slag as raw material ₃The product is the high value-added comprehensive utilization of the carbide slag. The invention adopts higher Ca ⁺Preparation of cubic CaCO from carbide slag leaching solution with concentration ₃The method has the advantages of high production efficiency, mild process conditions, low equipment requirements, cheap and easily available crystal form control agents, environmental protection and the like.

The invention relates to a method for preparing regular cubic light calcium carbonate from carbide slag, which takes carbide slag as raw material and NH ₄The Cl solution is used for leaching calcium ions in the carbide slag, then a crystal form control agent is added into the carbide slag leaching solution, and then (NH) is dripped ₄)HCO ₃The solution is reacted and then carbonized liquid is filtered, and the obtained filter cake is washed and dried to obtain cubic light CaCO ₃And (3) sampling. The method specifically comprises the following steps:

step 1: taking and measuring NH ₄Adding Cl into 500mL of deionized water, adding carbide slag (provided by a certain enterprise) dried at 110 ℃, reacting for 1h at room temperature, and filtering to remove solid impurities in the reaction solution to obtain certain Ca ²⁺Carbide slag leaching liquor (CaCl as main component) ₂Solution);

step 2: transferring a certain volume of the carbide slag leaching solution prepared in the step 1, and diluting the carbide slag leaching solution with deionized water to obtain the required Ca ²⁺CaCl of concentration ₂Solution, reaction total volume 300 mL; then according to a certain mass fraction (crystal form control agent and theoretically generated CaCO) ₃Mass ratio) is added into the crystal form control agent, the mixture is stirred and mixed evenly under the condition of certain temperature, and then a certain amount of (NH) is dripped into the mixture under stirring ₄)HCO ₃Timing the solution, reacting and aging for 10-40 min to obtain a carbonized liquid, performing solid-liquid separation on the carbonized liquid, washing and drying the obtained filter cake to obtain cubic CaCO ₃And (3) sampling.

In step 1, carbide slag and NH ₄The mass ratio of Cl is 1: 0.8.

In the step 2, the crystal form control agent is one of magnesium hydroxide, sodium polyacrylate or dodecyl trimethyl ammonium bromide, and the addition amount is CaCO ₃3-6% of theoretical yield.

In step 2, the resulting CaCl is diluted with deionized water ₂Ca in solution ²⁺The concentration is 0.3 to 0.8 mol.L ^-1。

In step 2, CaCl ₂And (NH) ₄)HCO ₃In the precipitation reaction, CaCl ₂And (NH) ₄)HCO ₃The molar ratio of (A) to (B) is 1:0.5 to 1: 1.5.

In step 2, diluting the obtained CaCl ₂Adding a crystal form control agent into the solution, uniformly mixing, and stirring and dropwise adding (NH) at the temperature of 25-50 DEG C ₄)HCO ₃Reacting and aging the solution for 10-40 min, and then carrying out solid-liquid separation to obtain a filtrate NH ₄Evaporating, concentrating and crystallizing the Cl solution to obtain NH ₄A Cl sample; washing and drying the obtained filter cake to obtain cubic CaCO ₃And (3) sampling.

Through detection, under the conditions, the prepared regular cubic light CaCO ₃Is pure-phase calcite type, and has an average particle size of 3-5 μm.

The single crystal control agent adopted by the invention is one of magnesium hydroxide, sodium polyacrylate or dodecyl trimethyl ammonium bromide, is low in cost and environment-friendly, and the prepared cubic light CaCO ₃The particle size is 3 to 5 μm. The invention has the advantages of mild reaction conditions, low equipment requirement, low cost of the crystal form control agent and the like.

Compared with the prior art, the invention has the following advantages:

1. the invention selects one of magnesium hydroxide, sodium polyacrylate or dodecyl trimethyl ammonium bromide as a single crystal form control agent to control CaCO ₃Growth of the particles, cubic CaCO produced ₃Uniform appearance, narrow particle size distribution and good dispersibility.

2. Compared with the prior cubic light CaCO ₃Compared with the preparation technology, the preparation method adopts the carbide slag as the raw material, and is beneficial to developing high value-added products of the carbide slag; and CaCl in the reaction system ₂The concentration is higher, and the production efficiency is higher.

3. The invention has the advantages of mild process conditions, low equipment requirements, cheap and easily available crystal form control agent, environmental protection and the like.

Drawings

FIG. 1 is a method for preparing regular cubic light CaCO by taking carbide slag as a raw material ₃The process flow diagram of (1).

FIG. 2 is a cubic light CaCO prepared in example 1 ₃XRD pattern of the product.

FIG. 3 is a cubic light CaCO prepared in example 1 ₃SEM image of the product.

FIG. 4 is a cubic light CaCO prepared in example 2 ₃SEM image of the product.

FIG. 5 is a cubic light CaCO prepared in example 3 ₃SEM image of the product.

FIG. 6 is a cubic light CaCO prepared in example 4 ₃SEM image of the product.

Detailed Description

The invention uses SU8020 electron microscope manufactured by Hitachi in Japan to observe the grain diameter and morphology of a sample, before testing, the sample is ultrasonically dispersed for 10min by ethanol, a dropper is used for dripping the sample on a cleaned silicon wafer, after surface gold spraying treatment, the test is carried out, and the acceleration voltage: 15 kV.

The following further description is made in conjunction with the accompanying drawings and specific examples: