Sodium Hydroxide 50% Membrane Grade (Caustic Soda, Lye)

Product Overview

Sodium Hydroxide 50% Membrane Grade is a highly concentrated aqueous solution of sodium hydroxide (NaOH), formulated for industrial use where strict quality and consistency are required. This technical grade caustic solution provides reliable pH adjustment, strong base strength, and compatibility with a wide range of chemical processes. Typical concentrations are optimized for membrane processes and applications demanding precise control of alkalinity, while the 50% w/w composition supports efficient mass transfer and handling in bulk reagent systems. The product is supplied as a clear, colorless liquid with a favorable density profile and low trace metal content to minimize contamination in sensitive syntheses and production lines.

In addition to pH control, this membrane-grade NaOH is commonly employed in chemical synthesis, soap production, food processing, and textile treatment workflows. Its high basicity supports saponification reactions, neutralization steps, and corrosion-control strategies in process streams. The material’s storage and handling guidance, aligned with established industry practices and applicable safety standards, ensures integrity during transport and on-site use. Clients can rely on consistent assay performance (near 50% w/w NaOH) and controlled impurity levels to meet process specifications and regulatory expectations.

Key Properties

• Property Name: 50% w/w NaOH solution (Membrane Grade)
• Chemical Formula: NaOH
• Molecular Weight: 40.00 g/mol
• Boiling Point: 100°C
• Specific Gravity: 1.18–1.26 at 20°C (typical 1.22)
• Assay (NaOH Content): 49–51% (typical 50%) by titration with standardized NaOH
• Color (APHA/Hazen): Max 10 (typical 5)
• Residue After Ignition: Max 0.05% (typical 0.01%)
• Chloride (Cl⁻): Max 100 ppm (typical 20 ppm)
• Nitrate (NO₃⁻): Max 50 ppm (typical 15 ppm)
• Sulfate (SO₄²⁻): Max 100 ppm (typical 20 ppm)
• Sodium (Na⁺): Max 2,000 ppm (typical 800 ppm)
• Iron (Fe): Max 0.1 ppm (typical 0.03 ppm)

Common Applications

• Application Category: pH Adjustment – Water treatment and industrial effluent systems use the caustic solution to attain and maintain target pH levels for corrosion control and precipitation processes.
• Application Category: Chemical Synthesis – Acts as a strong base for neutralization, hydrolysis, and various organic/inorganic synthesis routes, enabling controlled reaction environments.
• Application Category: Soap Production – Saponification reagent in fatty acid ester hydrolysis, enabling the production of bar and liquid soaps with consistent chain-length distributions.
• Application Category: Food Processing – Utilized for pH control and cleaning in processing lines, with strict impurity limits to meet regulatory cleanliness standards.
• Application Category: Textile Processing – Employed in scouring, bleaching, and alkaline steps to modify fiber properties and prepare textiles for dyeing.

Safety Precautions

Handling and storage should follow best practices for corrosive caustic solutions. Use corrosion-resistant containers (HDPE or stainless steel), ensure adequate ventilation, and wear appropriate PPE including chemical-resistant gloves, splash goggles, face shield, and acid-resistant apron. Store in a cool, dry place away from incompatible materials and acids, with secondary containment to manage any potential spills. Regularly inspect containers for signs of corrosion or leakage and keep containers tightly closed when not in use.

Emergency procedures require immediate flushing with plenty of water for exposed skin or eyes, removing contaminated clothing, and seeking medical attention for burns or inhalation exposure. Transport should comply with UN 1824, Sodium hydroxide solution, Class 8, PG II, and prevent cross-contamination with acids or organic materials. Refer to the SDS for comprehensive guidance on first aid, spill response, and incident reporting.

Benefits

✔ High Purity and Stability – Maintains low trace metal content and stable concentration for consistent process performance.
✔ Strong Base with Broad Compatibility – Effective in pH adjustment across water treatment, chemical synthesis, and cleaning regimes.
✔ Quality Assurance – Meets Technical Grade specifications with clear documentation (COA) supporting lot-to-lot reproducibility.