Preparation method of aragonite type calcium carbonate whiskers

Abstract

The invention relates to a method for preparing aragonite type calcium carbonate whiskers by using a calcium chloride-rich solution as a raw material. The method comprises the following steps of: 1) taking a certain amount of the calcium chloride-rich solution, and regulating the pH value of the solution to be neutral by using ammonia water or hydrochloric acid; 2) proportioning the solution obtained in the step 1) with ammonia water, putting the mixture into a reaction container with a stirring function for reaction, introducing CO2 gas at a certain speed while reacting, and controlling the concentration of calcium ions in the solution, the reaction temperature, the stirring speed and the amount of ammonia water in the reaction process; after the reaction is finished, performing suction filtration on the solution to obtain a solid reaction product and filtrate; and 3) washing and drying the solid product obtained in the step 2) to obtain the aragonite type calcium carbonate whisker material. The aragonite type calcium carbonate whisker material is non-toxic and safe, has the characteristics of high whiteness, good reinforcing property and the like, and can be applied to the industries of rubber, plastics, chemical engineering and the like.

Description

technical field [0001] The invention relates to a method for preparing aragonite calcium carbonate whiskers, in particular to a method for preparing aragonite calcium carbonate whiskers from a solution rich in calcium chloride without adding a crystal form control agent, which belongs to inorganic Functional materials and chemical materials. Background technique [0002] Calcium carbonate whisker is another new type of inorganic filler after nano-calcium carbonate. It is non-toxic, odorless, and white fluffy solid (needle-like single crystal under the microscope). As a new generation of filler material, it has the following properties and characteristics: (1) High mechanical strength with comprehensive performance, and functions such as vibration reduction, anti-skid, noise reduction, and wave absorption during use; (2) High friction coefficient, high wear resistance and heat resistance; (3) Thermal recession Good thermal recovery performance; (4) It can reduce the amount o...

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Problems solved by technology

[0003] At present, the main methods for preparing calcium carbonate whiskers are: (1) Carbonation method: mainly using natural limestone as raw material, the whole preparation process requires high-temperature calcination and adding crystal forms Control agent, higher energy consumption and cost

(2) Double decomposition method: soluble calcium salt and carbonate are mainly used as raw materials, the preparation process needs to be combined with other additional reagents, the aging time is long, the preparation process conditions are not easy to control and the requirements for raw materials are high

(3) Urea hydrolysis method: react urea with soluble calcium salts, no need to add crystal form control agent during the reaction process, but need to react under high temperature and high pressure, high energy consumption and high production risk

The process of this method is relatively complicated, difficult to operate, and the production efficiency is low

(5) High-gravity reaction crystallization method: This method has the advantages of less control factors in the reaction process, easy repeatability, and adjustable product particle size. However, this method needs to be carried out in a specific high-gravity reaction device, which requires extremely high equipment and energy consumption. larger

[0008] Dissertation Desulfurization Gypsum Preparation of Calcium Carbonate Whiskers and Its Mechanism Research discloses a kind of acid immersion solution of desulfurization gypsum carbonization product as raw material, prepared by double injection feeding method A calcium carbonate whisker with a diameter of 0.5-2 μm and an aspect ratio of 10-20. This method uses ammonium bicarbonate as a raw material, and the cost of additives is relatively high; in addition, the preparation process requires the use of a peristaltic pump to strictly control the drop rate of the reaction raw material. And it cannot exceed 2 mL per minute, the process conditions are relatively harsh, and industrial production is not used

[0009] In summary, the existing preparation technology of calcium carbonate whiskers has problems such as high raw material cost, complicated preparation technology, and the need to add a crystal form control agent. Therefore, the present invention Aiming at the defects of the above preparation methods of calcium carbonate whiskers, a new method for preparing high-whiteness aragonitic calcium carbonate whiskers at low temperature and normal pressure is invented using a solution rich in calcium chloride as a raw material without adding a crystal form control agent. method

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