Sodium gluconate concrete admixture has many functions in construction, such as water reducer and retarder, and it is widely used in industry.
Sodium gluconate is an organic substance with a chemical formula of C6H11NaO7. It has a wide range of industrial uses. Sodium gluconate can be used as a high-efficiency chelating agent in construction, textile printing and dyeing, metal surface treatment, water treatment and other industries, steel surface cleaning agent, glass bottle cleaning It can be used as a high-efficiency retarder and high-efficiency water-reducing agent in the concrete industry.
Application of sodium gluconate in construction
Concrete is a composite material made of cement, aggregates, admixtures and water. Concrete is the largest amount of all artificially manufactured materials. Three-quarters of concrete is aggregate, but the most active ingredient in concrete is cement slurry. The properties and performance of concrete are mainly determined by the properties of cement paste. The admixtures in concrete can provide some beneficial effects such as accelerating solidification, delaying solidification, making air bubbles exist, reducing water consumption and increasing plasticity, and so on. Usually several admixtures are used in cement at the same time, and various admixtures can reinforce each other in some applications.
Sodium gluconate can be used as an admixture in concrete. Its functions in concrete are as follows: water reducer and retarder
Sodium gluconate is generally used alone, but it can also be used in combination with other retarders such as carbohydrates and phosphates. Sodium gluconate is a crystalline powder. It is produced under properly regulated and controlled conditions. This compound is chemically pure and non-corrosive. The quality is constant. These features can ensure that it has reliable and reproducible results in the application.
Sodium gluconate as water reducer
By adding a water reducing agent, the water-cement ratio (W/C) can be reduced. The following effects can be obtained by adding sodium gluconate: 1. Improve workability. When the water-cement ratio (W/C) remains unchanged, adding sodium gluconate can improve workability. At this time, sodium gluconate acts as a plasticizer. When the addition amount of sodium gluconate is below 0.1%, the degree of improvement in workability is directly proportional to the addition amount. 2. Improve strength. When the cement content remains the same, the water content in the concrete can be reduced (that is, W/C is reduced). When the amount of sodium gluconate added is 0.1%, the amount of water added can be reduced by 10%. 3. Reduce cement content. The water and cement content is reduced in the same proportion, and the W/C ratio remains unchanged.
Sodium gluconate as retarder
Sodium gluconate can significantly delay the setting time of concrete. When the dosage is less than 0.15%, the logarithm of the initial setting time is directly proportional to the dosage, that is, the dosage is doubled, and the initial setting time is delayed to ten times, which makes the working time from very few The hours are extended to a few days without compromising the strength. This is an important advantage especially in hot weather and when it needs to be placed for a long time.
Used as a special cleaning agent for glass bottles
The beverage industry, food industry, and brewing industry have hundreds of millions of glass bottles per day, such as soda bottles, beer bottles, milk bottles, canned bottles, soy sauce bottles, wine bottles, etc. The cleaning work is a very important thing. The formulation of medicaments is a difficult technical task. An ideal medicine has not yet appeared in China. The main problems are: poor detergency, easy to block the nozzle and pipeline of the bottle washer; unsatisfactory de-staining power to bottle stickers and bottleneck rust; the trace residue after washing is not ideal for food safety (such as phosphate Residue); the washing water is discharged as a public hazard (not meeting the standards set by the country). If sodium gluconate is used as the main body in the formulation of the glass bottle cleaning agent, the above problems can be solved. (In the 1980s, large-scale experiments were carried out at the Shanghai Soda Plant and Shanghai Brewery, and the appraisal proved.) This application has not yet been developed in China. If a market is formed, the potential is great.
Used as water quality stabilizer
Because sodium gluconate has excellent corrosion and scale inhibition effects, it is widely used as a water quality stabilizer, for example, as a treatment agent for circulating cooling water systems in petrochemical enterprises, low-pressure boilers, and cooling water systems for internal combustion engines. Because it has the following special advantages:
⑴ It has obvious coordination effect. It is suitable for formulas such as molybdenum, silicon, phosphorus, tungsten, nitrite, etc. Due to the coordination effect, the corrosion inhibition effect is greatly improved.
⑵ The corrosion inhibition rate increases with the increase of temperature. Generally, corrosion inhibitors decrease with the increase of temperature, or even lose their effect completely. But sodium gluconate is just the opposite. The corrosion inhibition rate increases with the increase of temperature within a certain range. For example, in the test of carbon steel and other materials, the temperature rises from 77°F to 120°F, and its buffer rate increases by an average of 5%. above. Therefore, the peculiar characteristics of sodium gluconate are ideal for use as a corrosion inhibitor for higher temperature systems or systems with temperature changes from low to high temperatures.
⑶Strong anti-scaling ability: It has strong complexing ability to calcium, magnesium and iron salts, so it has strong anti-scaling ability, especially for Fe3+, which has excellent chelation effect, even in the whole PH range.
⑷ Eliminate public hazards. Using sodium gluconate as a corrosion and scale inhibitor for circulating cooling water to eliminate public hazards, which is an incomparable advantage to other corrosion and scale inhibitors used.
Used in medicine
Regulates the acid-base balance in the human body to restore the normal function of the nerves. It can also be used as a food additive for the same purpose.
The above is the role of sodium gluconate concrete admixture in construction.