Description
Around half of the sodium hydroxide production is used by manufacturers, prevalently in the paper industry. Other applications include the manufacturing of sodium salts and detergents, pH regulation, and organic synthesis.
In the petroleum industry, sodium hydroxide is utilized as an additive in drilling mud. It increases the mud viscosity and alkalinity in bentonite mud systems. Additionally, caustic soda neutralizes any acid gas encountered in the geological formation as drilling progresses. The process known as caustic washing utilizes caustic soda to clean and improve low quality crude oil. Treating with sodium hydroxide eliminates sulfurous impurities through reaction with weak acids.
Sodium hydroxide is broadly applied in the pulping of wood for creating paper or regenerated fibers. It plays a crucial role in several later stages of bleaching the brown pulp emerging from the pulping process. All of these stages require a strongly alkaline environment with a pH > 10.5 at the end of the phase.
Sodium hydroxide reacts with aluminum and water to produce hydrogen gas and sodium aluminate. This reaction converts a polished surface to a satin-like finish. In the biodiesel industry, anhydrous sodium hydroxide is a catalyst for the transesterification of methanol and triglycerides.
Food uses include washing or chemical peeling of fruits and vegetables, as well as chocolate, cocoa and soft drink processing, caramel coloring, poultry scalding, and thickening ice cream. Olives can be soaked in sodium hydroxide for softening. Furthermore, pretzels and German lye rolls are glazed with a sodium hydroxide solution before baking to achieve crispiness.
Another broad usage of sodium hydroxide is in the production of parts washer detergents. This includes defoamers, surfactants, and rust inhibitors. A parts washer heats detergent and water in a closed cabinet, spraying them at pressure against dirty parts for degreasing applications. While parts washer detergents based on sodium hydroxide are among the most aggressive parts washer cleaning chemicals, they are also considered environmental improvements over the solvent-based cleaning methods.
Stability/Shelf life
Hygroscopic. Air-sensitive.
Recommended storage: Must be stored in airtight containers to preserve its normality as it will absorb water from the atmosphere. Follow proper NaOH storage guidelines and maintain worker/environment safety.
Technical specification
| Items | Standards |
| Purity (NaOH), % | ≥99.0 |
| Na2CO3 content, % | ≤0.5 |
| NaCl content, % | ≤0.03 |
| Fe2O3 content, % | ≤0.005 |
| Flash point | non-combustible solids, but when in contact with water may generate sufficient heat to ignite combustible materials. |
| Melting point | 323 °C (613 °F, 596 °K) |
| Boiling point | 1388 °C (2530 °F, 1661 °K) |
| Density | 2.13 g/cm3 |
| Vapor pressure | <2.4 kPa (at 20 °C) |
| Water Solubility | Soluble |
| pH range | Strongly alkaline (1% solution) |
| Sensitivity | Air sensitive, Hygroscopic |
| Storage | In original container. Dry. Well closed. In an area without drain or sewer access. Separated from food and feedstuffs, strong acids and metals. |
| Shelf life/Retest | 24 months |
| Appearance | White crystalline pearls or flakes |
Reviews
There are no reviews yet.