The theory of lignin sulfonic acid
Lignin sulfonic acid is quite useful in various fields. It is unique in nature, widely used, and the production method is also exquisite.
1. Characteristics of lignin sulfonic acid
Lignin sulfonic acid has unique physical and chemical properties. Its color is often brown, or dark or light, depending on the raw material and production method. The texture is either powder, delicate and perceptible; or liquid, showing its characteristics between flows. It is soluble in water and forms a stable solution. This property makes it smooth in many application scenarios. And it has surface activity, which can reduce the surface tension of liquids and change the interface between different substances. This is one of its important properties.
Second, the application of lignin sulfonic acid
1. ** In the construction industry **, lignin sulfonic acid is often a key component of concrete admixtures. When mixed into concrete, it can improve its workability, making concrete easier to operate during mixing, transportation and pouring. And it can reduce water, reduce the water-cement ratio, and improve the strength and durability of concrete. Concrete modified by lignin sulfonic acid can maintain good performance in different environments and prolong the service life of buildings.
2. ** Agricultural field **, lignin sulfonic acid is also used. It can be made into fertilizer synergist, which can adjust the nutrient release rate of fertilizer after compounding with fertilizer. On the one hand, it delays nutrient loss, so that fertilizer nutrients can be supplied to crops for a long time; on the other hand, it promotes the absorption of nutrients by crops, enhances the resistance of crops, helps crops thrive, and improves the yield and quality of agricultural products.
3. ** In industrial production **, in the mineral processing process, lignin sulfonic acid can be used as a mineral processing dispersant. In the pulp system, it can make mineral particles evenly dispersed, avoid agglomeration, and improve mineral processing efficiency and concentrate quality. In the paper industry, it is a pulp cooking aid, which can accelerate the dissolution of lignin, reduce cooking energy consumption, and improve the water filtration performance of pulp, which is also beneficial to the quality of paper.
Third, the production of lignin sulfonic acid
The production of lignin sulfonic acid is mostly from the by-products of the paper industry. In the papermaking process, after extracting cellulose from wood and other raw materials, the remaining black liquor is rich in lignin. After a series of chemical treatments, such as acidification and sulfonation, the lignin is converted into lignin sulfonic acid. First, the black liquor is pretreated to remove impurities and adjust its pH. Then, under suitable temperature and pressure conditions, a sulfonating agent is added to carry out a sulfonation reaction, so that the lignin molecules are introduced into the sulfonic acid group, thereby giving it new properties. After the reaction is completed, the lignin sulfonic acid products of different purity and specifications can be obtained through separation and purification processes. The production process requires accurate control of the parameters of each link to ensure the stability of product quality and excellent performance.
