93%-97%，Sodium lignosulfonate CAS 8061-51-6

What is sodium lignosulfonate? What are its uses?

1. What is Sodium lignosulfonate?

Sodium lignosulfonate (also called sodium lignin sulfonate, or sodium lignin sulfonate, sulfonated lignin sodium salt, also known as lignin sodium) is a natural anionic surfactant with high molecular weight, extracted and purified from sulfite pulping wastewater. It is also one of the most commonly used lignin derivatives in the industrial field. The composition can be reduced to:

Sodium lignosulfonate (CAS No.: 8061-51-6, a natural high molecular weight polymer with no fixed molecular formula).

It is a brownish-brown powder at room temperature (it also exists in liquid form), easily soluble in water, and has various properties such as dispersion, water reduction, binding and chelation. Sodium lignosulfonate is a typical anionic polymeric surfactant composed of a lipophilic lignin skeleton and a hydrophilic sulfonic acid group (-SO3Na). It can disperse and suspend solid particles in water and can chelate polyvalent metal ions such as calcium, magnesium.

Sodium lignosulfonate is the result of comprehensive utilization of sulfite pulping waste liquor of papermaking industry from the source. It converts the “black liquor”, an environmental burden at the start, into a green chemical with economic value. It is a typical renewable biomass resource chemical product, in line with the concepts of green environmental protection and circular economy.

Chemically, sodium lignosulfonate is a natural high molecular weight surfactant. It is chemically stable, acid and alkali resistant, biodegradable and low toxicity. It requires a small dosage and is highly effective as a dispersant and its price is more advantageous than petroleum-based dispersants. It should be kept in an air-tight, moisture-proof container.

The product is classified by application area and generally includes: technical/industrial grade (for industrial applications such as concrete, drilling fluids, and coal-water slurry), dye and pesticide grade (for dye dispersion and pesticide formulation), feed grade (for animal feed binding), and water treatment grade. The requirements for purity and hygiene control are different for different grades. Special attention is paid to the following indicators:

1. reducing sugar content

Reducing sugars reflect sugar impurities in pulping waste liquor, affecting product performance (such as water reduction rate in concrete), and must be controlled within a reasonable range.

2. Water-insoluble matter

Water-insoluble matter reflects the total amount of impurities, affecting solubility and application performance. Industrial grade generally requires less than 0.3% and must be strictly controlled.

3. Moisture

Moisture content affects product storage stability and the accuracy of ingredient addition; moisture content must be strictly controlled for powder products.

4. pH value

pH value affects product properties and formulation compatibility, and must be controlled within the labeled range to ensure compatibility with concrete, dye, and other systems.

5. Ash and sulfate

Ash and sulfate content reflect the content of inorganic impurities, affecting product purity and application performance, and must be controlled within a reasonable range.

6. Heavy metal content

Feed-grade products must keep heavy metals (such as lead, arsenic, and cadmium) within regulatory limits to ensure the safety of animal feed.

II. What are the uses of Sodium lignosulfonate?

As a kind of “natural polymeric surfactant”, sodium lignosulfonate has unique properties and extremely wide applications in construction, textile, agriculture, aquaculture and environmental protection.

1. Concrete water reducing agent (core industry application)

Sodium lignosulfonate is a traditional concrete water reducer and plasticizer (normally used between 0.2%-0.5% of the cement dosage). It helps to improve concrete workability, reduce water consumption and increase strength. It has price advantage and is widely used in cost sensitive projects It is the largest downstream product of lignin in output.

2.Dye Dispersants (Core application for dye grade products)

Sodium lignosulfonate is an important grinding auxiliary used for dispersing dyes. It helps in keeping dye particles in suspension stably in the dye liquor and prevents aggregation. It is widely used in the production and printing and dyeing process of disperse dyes, reactive dyes and pigments.

3. Drilling mud diluent and dispersant (commercial grade)

Refined lignin sulfonates are used as diluents, dispersants and viscosity reducers in oil drilling mud, helping to control the rheological properties of mud and stabilizing the wellbore. They are important additives in oil and gas drilling industry.

4.Coal water slurry additive (industrial grade)

Sodium lignosulfonate is a dispersant and stabilizer for coal-water slurry, which helps to disperse coal powder evenly in water, decrease viscosity, and improve the concentration and stability of the slurry, thus benefiting the coal chemical and clean energy industries.

5.Water-reducing agent for ceramics and refractory materials (industrial grade)

Sodium lignosulfonate is used as a water-reducing and dispersing agent in the building ceramics and refractory materials industries to help reduce molding moisture and improve the strength of the blank in ceramic blanks, glazes and refractory materials.

6. Feed binders (core application in feedgrade)

Feed grade sodium lignosulfonate is used as a binder for pelleted feed to help feed powder bind and form, improve pellet hardness and durability, and reduce transportation losses. It is a commonly utilized binding agent in the feed industry.

7.Water treatment scale inhibitors and dispersants (water treatment grade)

Sodium lignosulfonate is used as a scale inhibitor and dispersant in circulating cooling water and boiler water, which can promote the chelation of calcium and magnesium ions, disperse scale and suspended solids, and be used as a chelating agent for heavy metals, so as to serve the industrial water treatment industry.

8.Industrial grade additives for resins and rubbers

Sodium lignosulfonate is used as a modifier for resins such as phenolic resins and as a rubber processing aid for better processing performance and product properties. It is also used in glues.

9.Industrial grade asphalt emulsifier

In the road construction and waterproofing materials industry, emulsified asphalt is used as a binder ingredient, while sodium lignosulfonate is used as an emulsifying stabilizer to help asphalt to form a stable emulsion in water.

10. Ore flotation agent (industrial grade)

Sodium lignosulfonate is an auxiliary reagent used in mineral flotation to improve flotation separation results and is used in the mining and mineral processing industry.

11.Industrial cleaning products

Sodium lignosulfonate has chelating, dispersing and detergent-aiding properties and is therefore suitable as an environmentally friendly additive in industrial cleaning formulations. It is especially suitable for descaling circulating cooling water systems and cleaning heat exchangers and precision components. It can chelate calcium and magnesium ions in water and disperse scale, oily suspended solids, prevent scale adhesion and deposition, and has good biodegradability. It is a raw material of green cleaning. It is often used together with other surfactants.

12.Soil improvement

Sodium lignosulfonate can be used as a soil conditioner to improve the soil aggregate structure, increase the soil porosity and improve the water and fertilizer retention capacity. It can enhance drainage and aeration of compacted clay soils and stabilize sand and soil of sandy soils . It can also chelate trace elements such as iron, zinc and copper, reduce the leaching of nutrients and improve the absorption and utilization rate of nutrients by plants. It can also be used in the experiments of sand fixation in desertification areas.

13. Pigments and carbon black dispersions

It is used as a low-cost and environment-friendly dispersant in the wet grinding process of carbon black and inorganic/organic pigments, based on electrostatic repulsion and steric hindrance effects, to prevent the agglomeration and sedimentation of solid particles, reduce system viscosity, improve the storage stability of color paste and improve color uniformity. It is widely used in inks, water-based coatings, masterbatches, rubber color matching and other applications.

Summarize

Sodium lignosulfonate (CAS No. 8061-51-6) is a natural anionic surface active agent with high molecular weight which is obtained and purified from the waste water of sulfite pulping. It is a brown-red powder, soluble in water, and its unique dispersing, water reducing, binding and chelating properties make it one of the most widely used lignin derivatives and green chemicals. We see it in every day life in concrete construction, textile dyeing, pesticide formulations, ceramic products, animal feed, and water treatment. Sodium lignosulfonate is widely used in applications as concrete water-reducing agents, dye dispersants, pesticide formulation adjuvants, drilling mud diluents, coal-water slurry additives, ceramic water-reducing agents, feed binders, water treatment scale inhibitors, resin and rubber additives, asphalt emulsifiers, and ore flotation agents. It is a green multi-functional chemical connecting “natural high-molecular-weight surfactant chemistry” to “construction, textile, agriculture, animal husbandry and environmental protection”.