Sodium Hydroxide Solution (content ≥30%) is a colorless or slightly colored, transparent, viscous liquid at room temperature, exhibiting strong hygroscopicity and corrosiveness. Its chemical properties are consistent with those of solid sodium hydroxide, characterized by extremely strong alkalinity and reactivity: it can neutralize acids, react with amphoteric metals to produce hydrogen gas, and saponify fats and oils. As a high-concentration solution, its reactions are typically more vigorous. Leveraging its high concentration, ease of transportation, and metering convenience, its primary industrial application is as a liquid-form strong alkali raw material and treatment agent. It is used directly on a large scale in processes such as pulping in papermaking, textile dyeing and printing, chemical synthesis (e.g., production of soaps and dyes), petroleum refining, water treatment (pH adjustment, neutralization of acidic wastewater), and alumina production.