Introduction: Why Paper Mills Depend on Aluminium Sulphate
In the complex world of papermaking, few chemicals offer as much versatility and performance enhancement as Aluminum Sulphate (Alum). Whether you’re producing fine-quality printing paper, packaging board, or specialty grades, aluminum sulphate plays a crucial role in improving retention, sizing, brightness, and overall sheet quality.
At Vinipul Chemicals Pvt. Ltd., we manufacture and supply high-purity aluminum sulphate suitable for both acidic and neutral papermaking processes. With ISO, GMP, and FSSAI certifications, and a strong footprint across India and export markets, we cater to the evolving needs of modern paper mills and chemical integrators.
What is Aluminum Sulphate?
Chemical Name: Aluminum Sulphate
Common Names: Alum, Paper Alum, Al2(SO4)3
CAS Number: 10043-01-3
Molecular Weight: 342.15 g/mol
Appearance: White crystalline powder or lumps
Solubility: Highly soluble in water
pH (1% solution): ~3.5 (acidic)
Aluminum sulphate is produced by reacting aluminum hydroxide or bauxite with sulfuric acid, yielding a compound that dissolves rapidly in water and reacts with various components of the paper pulp to modify fiber behavior, improve drainage, and enhance printability.
Key Technical Properties of Aluminum Sulphate (Vinipul Grade)
| Property | Value / Description |
|---|---|
| Grade | Technical / Industrial / Water treatment |
| Al₂O₃ Content | 16% – 17% (customizable up to 18%) |
| Physical Form | Powder / Lumps |
| Color | White / Off-white |
| pH (1% solution) | 3.0 – 4.0 |
| Solubility in Water | 100% soluble |
| Iron Content (Fe₂O₃) | < 0.01% |
| Moisture Content | < 1% |
| Packaging | 25 / 50 kg HDPE bags or jumbo bags |
🧪 Vinipul Chemicals ensures consistent mesh size and solubility for faster reaction rates and process compatibility.
How Aluminum Sulphate Works in Paper Manufacturing
In papermaking, aluminum sulphate acts as a multifunctional process aid, especially in systems using acidic or mildly neutral pH.
🟢 1. Sizing Agent Fixation (Internal & Surface Sizing)
- Alum helps anchor rosin size and alkyl ketene dimer (AKD) to cellulose fibers.
- This makes paper more resistant to water, ink bleeding, and humidity.
- Critical for packaging boards, writing papers, and copier sheets.
🟠 2. Dye Fixation & Brightness Enhancement
- Alum improves retention of anionic dyes, making colors brighter and more uniform.
- Especially useful in tinted or printed sheets where dye strength is critical.
🔵 3. Filler & Fiber Retention Aid
- Improves binding of calcium carbonate, kaolin clay, and titanium dioxide
- Ensures less loss in white water, improving process economics
🟣 4. Pitch and Resin Control
- Neutralizes colloidal pitch particles (resin, wax, glue), preventing deposition on rolls
- Reduces machine downtime and improves surface finish
🟡 5. Drainage and Drying Efficiency
- Promotes flocculation, leading to faster water removal during forming
- Cuts energy cost during pressing and drying stages
Applications Across Paper Grades
| Paper Type | Role of Aluminum Sulphate |
|---|---|
| Writing & Printing Paper | Internal sizing, dye fixation, fiber retention |
| Copier & Laser Paper | Enhanced sheet strength, moisture resistance |
| Kraft Linerboard & Cartons | Pitch control, wet strength improvement |
| Coated Paper (Art Paper) | Pigment binding, drainage aid |
| Tissue Paper & Napkins | Wet-end charge control, aid in filler retention |
| Specialty Papers (Security, Map) | Color brightness, coating compatibility |
Vinipul’s customized grades ensure compatibility with varied pulp sources, machine speeds, and additive systems.
Global Demand & Export Outlook
With rising demand for cost-effective, high-performance sizing agents, aluminum sulphate continues to dominate as a staple in papermaking chemicals, particularly in Asia-Pacific, Middle East, and Africa.
📈 High-Growth Markets:
- India – Due to increased paper consumption in FMCG and packaging
- Vietnam & Bangladesh – Low-cost paper production for domestic and export use
- UAE, Oman, Egypt – Importers of acid-process chemicals for multi-grade paper mills
Why Global Buyers Choose Vinipul:
- 🇮🇳 Made in India – Competitive pricing with quality assurance
- 🧪 Custom Batch Support – pH, Al₂O₃ % tailored to your pulp system
- 🏭 Bulk Dispatches – Factory-to-port delivery model with inventory management
- 📑 Complete Docs – COA, MSDS, packing list, export invoice, regulatory clearance
Whether you need 5 MT or 500 MT, we ensure consistency, performance, and compliance.
📦 Packing, Safety & Storage Guidelines
| Parameter | Specification |
|---|---|
| Packaging | 25/50 kg HDPE woven sacks with liners, jumbo bags |
| Storage Instructions | Keep in dry, well-ventilated areas, sealed bags |
| Shelf Life | 2 years from manufacturing date |
| Hazard Classification | Non-hazardous under transport regulations |
| Precautions | Use gloves/masks when handling powder |
✅ Compliant with REACH, GHS, and BIS labeling.
✅ Vinipul also provides neutral pH alum variants for low-acid systems.
FAQs
❓ What is the role of aluminum sulphate in papermaking?
Answer: It improves internal sizing, dye retention, drainage, and pitch control in acidic and mildly neutral paper processes.
❓ Is aluminum sulphate suitable for all types of paper?
Answer: Yes, it is widely used in writing, printing, packaging, tissue, and board manufacturing, especially where water resistance or brightness is needed.
❓ What is the typical percentage of aluminum sulphate used in papermaking?
Answer: Usage ranges from 2% to 7% based on pulp type, process chemistry, and sizing requirements.
❓ Is aluminum sulphate safe to use in food-grade paper?
Answer: Yes, if processed under GMP and FSSAI guidelines. Vinipul supplies such compliant grades on request.
❓ Can aluminum sulphate be exported internationally?
Answer: Absolutely. Vinipul exports to Asia, Africa, and the Middle East with complete port-handling support and regulatory documents.
❓ How can I ensure compatibility of alum with my mill process?
Answer: Share your pH, pulp source, and target output with us. Our technical team will recommend a grade optimized for your system.
Why Choose Vinipul Chemicals Pvt. Ltd.?
🏭 Manufacturer & Exporter – Based in Mumbai, with modern plant in Taloja
🧪 Specialized Grades – For pulp mills, dye houses, and neutral paper processes
📦 Bulk Supply Ready – From 25 kg bags to container loads
🔍 Quality Control Lab – In-house Al₂O₃ & pH testing, mesh uniformity
🌍 Export Experts – Full set of documentation for global compliance
🤝 Customer Support – Pre-sales tech assistance, samples, and live consultations
From sourcing to supply chain, we help paper manufacturers reduce cost, improve consistency, and achieve better surface quality – with every delivery.
