Caustic Soda Flakes 99% (Sodium Hydroxide - Pure NaOH Flakes) 25kg Bag

Caustic Soda Flakes 99% NaOH China – High-Purity Ion-Exchange Membrane Sodium Hydroxide Flakes (25Kg Bag)

Caustic soda flakes 99 (chemical designation: Sodium Hydroxide Flakes 99, molecular formula NaOH) is an industrial-strength, ultra-pure alkaline compound directly imported from China. Compliant with Chinese National Standard GB 209-2006 (Superior Class), this refined naoh 99 china 25kg bag delivers a guaranteed active alkaline assay of minimum 99.0% Min. Produced via advanced ion exchange membrane caustic soda technology, it features trace levels of sodium chloride (NaCl ≤ 0.03%) and ferric oxide (Fe₂O₃ ≤ 0.005%), dissolving into a sparkling clear alkaline liquor without sediment or discoloration. Packaged in UN-certified dangerous goods packaging (5H3/Y26/S/26), this industrial caustic soda flakes formulation is the premier chemical reagent for high-end textile mercerization, electroplating degreasing, and advanced wastewater neutralization, making it the top choice for commercial facilities seeking to buy sodium hydroxide 99 bulk at competitive wholesale prices.

Technical Specification Standards – Caustic Soda Flakes 99% (GB 209-2006 Superior Class)

Chemical Dynamics & Key Technological Advantages

• Advanced Ion-Exchange Membrane Electrolysis: Unlike traditional diaphragm electrolysis that leaves high residual chloride salt, the modern ion-exchange membrane process selectively permits sodium cations (Na⁺) to migrate across the fluoropolymer membrane while blocking chloride anions. This achieves an exceptional assay of ≥ 99.0% NaOH with chlorides suppressed to ≤ 0.03% and iron oxide to ≤ 0.005%.
• Crystal-Clear Dissolution with Zero Sediment: Due to minimal iron and carbonate contamination, dissolving 99% flakes creates a water-clear alkaline liquor without haziness or sediment accumulation. This preserves the brightness of dyed textiles and prevents nozzle blockages in automated chemical metering circuits.
• High Alkaline Reactivity & Rapid Saponification: At 99% concentration, the chemical dissociates completely into univalent sodium cations (Na⁺) and hydroxyl anions (OH⁻). The immediate availability of high OH⁻ drives rapid pH neutralization in wastewater streams and hydrolyzes ester linkages in industrial fats and greases (saponification), achieving superior cleaning efficiency at lower dosage rates than 96% or 98% grades.
• UN-Certified 5H3/Y26/S/26 Heavy-Duty Packaging: Sodium hydroxide is intensely hygroscopic and susceptible to atmospheric carbonation. The standardized 25.0 kg package features a heavy-duty woven plastic outer bag paired with an airtight virgin polyethylene inner liner, preventing atmospheric moisture absorption, caking, and chemical degradation during humid storage.

Core Industrial Applications of Caustic Soda Flakes 99%

Engineered for high chemical consistency and low iron contamination, caustic soda flakes 99 serves demanding industrial applications:

• Premium Textile Scouring & Mercerization:
  • Mercerization: Immersing raw cotton fibers in concentrated caustic solution causes cell walls to swell uniformly, permanently increasing tensile strength, silky surface luster, and dye uptake.
  • Scouring: Strips natural pectins, waxes, and lubricating sizing oils from greige cotton fabrics without depositing iron residues that cause fabric yellowing.
• Wastewater Treatment & Effluent Neutralization:
  • Adjusts and neutralizes pH in acidic effluent streams from semiconductor manufacturing, electronics plating, and chemical processing facilities.
  • Provides an alkaline medium to precipitate toxic heavy metal ions (Fe, Al, Cu, Ni, Cr) as insoluble metal hydroxides prior to secondary flocculation with PAC.
• Personal Care, Soaps & Specialty Detergents: Acts as the primary alkaline reactant in fat saponification to produce high-grade bar soaps, liquid detergents, and industrial CIP (Clean-In-Place) cleaning agents.
• Pulp & Paper Manufacturing: Depolymerizes natural lignin binders from cellulose wood chips in chemical pulping, aiding the bleaching of high-brightness papers.
• Electroplating & Precision Metal Finishing: Strips stubborn grease films, drawing lubricants, and surface oxides from metal substrates before powder coating or electrolytic plating.

Technical Dosing Guidelines, Safe Dissolution & Storage Protocols

• MANDATORY DISSOLUTION PROTOCOL (EXOTHERMIC HAZARD):
  • ALWAYS SLOWLY ADD CAUSTIC SODA FLAKES INTO WATER while continuously stirring to disperse generated heat. Dissolving solid NaOH in water is intensely exothermic (ΔH < 0), releasing significant thermal energy that can heat the solution near boiling temperatures.
  • NEVER ADD WATER DIRECTLY ONTO DRY CAUSTIC SODA FLAKES. Pouring water onto concentrated dry flakes triggers localized flash boiling and steam explosions, splattering boiling concentrated alkaline solution that causes catastrophic chemical burns.
• Equipment & Tank Metallurgy: Dissolve and store caustic solutions only in tanks, piping, and agitators fabricated from high-density polyethylene (HDPE), polypropylene (PP), PVC, or stainless steel (SUS 304/SUS 316). Never use aluminum, zinc, tin, or galvanized steel vessels, as caustic soda aggressively attacks amphoteric metals to generate explosive hydrogen gas (H₂).
• Warehouse Storage Protocol (UN 1823 Class 8 PG II): Store bags on elevated pallets at least 20 cm above floors in a dry, well-ventilated dedicated warehouse with an intact roof. Protect strictly against water leaks and moisture.
• Chemical Segregation: Store strictly isolated from strong mineral acids (HCl, H₂SO₄, HNO₃), strong oxidizing agents, and reactive metals. Tightly reseal inner PE liners immediately after partial use to prevent rapid atmospheric moisture absorption, liquification, and carbonate crust formation.

Commercial Supply Policy at THP Chemical

Tan Hung Phu Chemical Co., Ltd. (THP Chemical) is a direct importer and wholesale distributor of Caustic Soda Flakes 99% NaOH (25kg Bag China) supplying municipal wastewater authorities, textile operations, and industrial manufacturing facilities nationwide:

• Certified compliant with National Standard GB 209-2006 (Superior Class), guaranteeing active assay NaOH ≥ 99.0% Min and Fe₂O₃ ≤ 0.005%.
• Original packaging: 25.0 KGS Net (Total Gross Weight: 25.1 KGS), compliant with UN dangerous goods packaging standard 5H3/Y26/S/26.
• Comprehensive compliance documentation: Batch-specific Certificate of Analysis (COA), 16-section Material Safety Data Sheet (MSDS), and legal VAT invoices provided with each dispatch.
• Extensive inventories maintained at our central Ho Chi Minh City logistics center, supporting rapid palletized dispatch nationwide at competitive wholesale volume pricing.

Frequently Asked Questions (FAQ)

1. What are the key advantages of 99% membrane caustic soda flakes over standard 96% or 98% grades?

Membrane-grade 99% caustic soda flakes feature significantly lower levels of residual salts (NaCl ≤ 0.03%) and iron impurities (Fe₂O₃ ≤ 0.005%). While lower-grade caustic soda may impart slight haze or yellowing in solution, 99% flakes dissolve into a water-clear solution with higher chemical reactivity and zero sediment, protecting stainless steel equipment against pitting corrosion.

2. Why is low iron oxide (Fe₂O₃ ≤ 0.005%) mandatory in high-end textile mercerization?

Iron impurities react with reactive dyestuffs and optical brighteners, creating fabric discoloration, dull shades, and yellow spots. Superior Class 99% caustic flakes restrict iron oxide to ≤ 0.005%, ensuring complete dissolution into a water-clear solution that protects fabric whiteness and guarantees precise dye batch reproducibility.

3. What does the dangerous goods packaging code 5H3/Y26/S/26 signify?

This code certifies compliance with United Nations (UN) packaging standards: 5H3 designates a woven plastic bag with an inner moisture-barrier liner; Y26 confirms the package satisfies tests for Packing Group II dangerous goods up to a maximum gross mass of 26 kg; S indicates packaging designed specifically for hazardous solid substances; and 26 represents the packaging manufacturing certification year.

4. Does THP Chemical provide batch COAs and commercial VAT invoices for bulk orders?

Yes. THP Chemical supplies batch-specific factory Certificates of Analysis (COA), 16-section MSDS sheets, and legal commercial VAT invoices with every wholesale order to satisfy corporate procurement, environmental auditing, and safety compliance requirements.