阅读说明：本技术 一种无碱速凝剂的制备方法 (Preparation method of alkali-free accelerator ) 是由 张军航 于 2020-06-15 设计创作，主要内容包括：本发明公开了一种无碱速凝剂的制备方法,无碱速凝剂以质量百分数计配方为：氟硅酸5-7％,氢氧化铝3-5％,硫酸铝19-25％,柠檬酸5-10％,多羟基分散增强剂1-3％,稳定剂0.5-1％,余量为水。本发明以氟硅酸铝、氟化铝、硫酸铝、柠檬酸、多羟基分散增强剂、稳定剂为主要成分组成的无碱液体速凝剂,借助于氟铝络合溶液优异的促凝作用,速凝性能好。(The invention discloses a preparation method of an alkali-free accelerator, which comprises the following components in percentage by mass: 5-7% of fluosilicic acid, 3-5% of aluminum hydroxide, 19-25% of aluminum sulfate, 5-10% of citric acid, 1-3% of polyhydroxy dispersion enhancer, 0.5-1% of stabilizer and the balance of water. The alkali-free liquid accelerator consists of aluminum fluosilicate, aluminum fluoride, aluminum sulfate, citric acid, polyhydroxy dispersion reinforcing agent and stabilizer as main components, and has good accelerating performance by virtue of the excellent accelerating action of a fluorine-aluminum complex solution.)

1. A preparation method of an alkali-free accelerator is characterized by comprising the following steps: the alkali-free accelerator comprises the following components in percentage by mass: 5-7% of fluosilicic acid, 3-5% of aluminum hydroxide, 19-25% of aluminum sulfate, 5-10% of citric acid, 1-3% of polyhydroxy dispersion enhancer, 0.5-1% of stabilizer and the balance of water; the preparation method comprises the following steps:

s1, weighing fluosilicic acid and aluminum hydroxide according to a proportion, mixing the two, reacting to produce a mixture A of the fluosilicic acid, the aluminum fluoride, the silicon dioxide and water,

s2, preparing an aluminum sulfate solution, and adding citric acid to form a mixture B

S3, mixing the mixture A obtained in the step S1 with the mixture B obtained in the step S2, adding a polyhydroxy dispersion enhancer and a stabilizer, and supplementing the balance of water, and uniformly stirring to obtain the alkali-free accelerator.

2. The method for producing an alkali-free accelerator according to claim 1, characterized in that: the alkali-free accelerator comprises the following components in percentage by mass: 6% of fluosilicic acid, 4% of aluminum hydroxide, 23% of aluminum sulfate, 6% of citric acid, 1% of polyhydroxy dispersion enhancer, 01% of stabilizer and the balance of water.

Technical Field

The invention relates to the technical field of setting accelerators, in particular to a preparation method of an alkali-free setting accelerator.

Background

The accelerator is an additive commonly used for concrete, the alkali-free accelerator is added into the concrete, so that the coagulation and hardening speed of the cement can be accelerated, the early strength is improved, the influence of the later strength is small and even is not reduced, the cohesiveness and the bonding strength of the concrete and mortar are greatly improved, the rebound rate is reduced, the material loss caused by rebound is effectively reduced, the economic benefit is improved, the alkaline cement dust in the air is reduced, the environment is protected, and the construction progress is accelerated. However, hydrofluoric acid is generally contained in the alkali-free setting accelerator. For example, CN110255955A discloses an alkali-free liquid accelerator, which is characterized in that the alkali-free liquid accelerator comprises the following raw materials in percentage by mass: aluminum sulfate: 45% -55%, nano alumina: 5% -10%, hydrofluoric acid: 5% -10%, solubilizing component: 3% -7%, fluorosilicate: 2-6%, early strength component: 1% -4%, stabilizing components: 0.5-1%, water: 20 to 32 percent. The hydrofluoric acid dosage of the alkali-free liquid accelerator is up to 5-10%.

Disclosure of Invention

The invention aims to provide a preparation method of an alkali-free accelerator. The alkali-free liquid accelerator consists of aluminum fluosilicate, aluminum fluoride, aluminum sulfate, citric acid, polyhydroxy dispersion reinforcing agent and stabilizer as main components, and has one aluminum fluoride system with fluorine content of about 4.5% and aluminum content of 5% and excellent coagulation promoting effect of aluminum fluoride complex solution. Fluosilicic acid is used as a raw material to replace hydrofluoric acid, so that the cost is saved and the method is safer.

In order to achieve the purpose, the invention adopts the following technical scheme: the preparation method of the alkali-free accelerator comprises the following steps: 5-7% of fluosilicic acid, 3-5% of aluminum hydroxide, 19-25% of aluminum sulfate, 5-10% of citric acid, 1-3% of polyhydroxy dispersion enhancer, 0.5-1% of stabilizer and the balance of water; the preparation method comprises the following steps:

s1, weighing fluosilicic acid and aluminum hydroxide according to a proportion, mixing the two, reacting to produce a mixture A of the fluosilicic acid, the aluminum fluoride, the silicon dioxide and water,

s2, preparing an aluminum sulfate solution, and adding citric acid to form a mixture B;

s3, mixing the mixture A obtained in the step S1 with the mixture B obtained in the step S2, adding a polyhydroxy dispersion enhancer and a stabilizer, and supplementing the balance of water, and uniformly stirring to obtain the alkali-free accelerator.

Further preferably, the alkali-free accelerator comprises the following components in percentage by mass: 6% of fluosilicic acid, 4% of aluminum hydroxide, 23% of aluminum sulfate, 6% of citric acid, 1% of polyhydroxy dispersion enhancer, 01% of stabilizer and the balance of water.

The invention has the beneficial effects that: fluosilicic acid is used as a raw material to replace hydrofluoric acid, so that the cost is saved and the safety is higher; the alkali-free liquid accelerator consists of aluminum fluosilicate, aluminum fluoride, aluminum sulfate, citric acid, polyhydroxy dispersion reinforcing agent and stabilizer as main components, and has one aluminum fluoride system with fluorine content of about 4.5% and aluminum content of 5%, and excellent coagulation promoting effect of aluminum fluoride complex solution to form excellent coagulation accelerating performance.

Detailed Description

The technical solutions of the present invention will be described clearly and completely with reference to the following embodiments, and it should be understood that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments.