Sodium lignin sulfonate, commonly abbreviated as wood sodium in the industry, is a natural aromatic polymer compound derived from by-products of the papermaking industry. It is also a widely used anionic polymer surfactant, with CAS number 8061-51-6. Relying on biomass extraction and production, it combines natural environmental protection, diverse performance, and low cost. It is an indispensable green additive in industrial production and widely adapts to the refined production needs of multiple industries.
In terms of source and preparation, sodium lignin sulfonate is a core byproduct of the papermaking and pulping process. In industrial production, crude lignin is extracted from pulping waste liquid from biomass raw materials such as bamboo, wood, and straw, then refined through sulfonation modification, concentration purification, and spray drying. The entire process relies on the resource utilization of industrial waste, with broad raw material sources, low production costs, and alignment with the concept of circular economy development. The finished product is a yellow-brown to brownish free-flowing powder with a uniform texture, slight hygroscopic, and stable chemical properties under sealed storage conditions, making it resistant to decomposition and spoilage.
Its physicochemical properties are highly distinctive in application. Physically, sodium lignosulfonate is easily soluble in ambient temperature water, forming a stable brownish colloidal solution. Its dissolution rate increases significantly with increasing water temperature and thorough stirring. It is insoluble in conventional organic solvents such as ethanol and acetone, and its aqueous solution does not precipitate or stratify, making it suitable for various aqueous system production scenarios. Chemically, its aqueous solution has a pH between 7.0 and 9.0, is weakly alkaline, and its molecular structure contains active functional groups such as sulfonic acid groups, hydroxyl groups, and carboxyl groups. It possesses excellent surface activity, dispersibility, binding, and emulsifying properties, while also possessing good chemical stability and biodegradability, leaving no residual pollution, making it a typical environmentally friendly chemical additive.
Core functional features are the core support for its widespread application. First, strong dispersion performance, which can quickly adsorb onto the surface of solid particles, effectively reducing surface tension, preventing particle agglomeration and settling, and ensuring the powder material is evenly dispersed in aqueous solution; Second, excellent adhesion, providing strong bonding and forming for various powders and granular materials, assisting in granulation and briquette formation; Third, emulsification stabilization capability, which can stabilize water-in-oil emulsion systems and prevent emulsion breakage and layering; Fourth, it has good compatibility, making it compatible with most inorganic salts, surfactants, and organic additives, without antagonistic reactions, and is suitable for complex industrial formulation systems. Compared to chemical synthesis additives, sodium lignosulfonate is naturally biodegradable, non-toxic, harmless, and highly cost-effective, making it the preferred material for green alternative additives across various industries.