| Product Name | Potassium Sulfate (Potassium Sulphate) |
| Common Name | Sulfate of Potash (SOP) |
| Product Definition | A high-quality, chlorine-free potassium fertilizer, providing both potassium (K₂O) and sulfur (S) essential nutrients for crops. |
| CAS No. | 7778-80-5 |
| EINECS No. | 231-915-5 |
| Molecular Formula | K₂SO₄ |
| Molecular Weight | 174.26 |
| Form Type | White or light yellow crystalline powder or granules. Granular SOP has excellent physical properties with lower hygroscopicity than MOP, making it easier to store and transport. |
| Key Physical & Chemical Properties | Non-hygroscopic, stable at room temperature; insoluble in ethanol and ether; highly soluble in water; chemically neutral and physiologically acidic; melting point >1069℃; pH (5% solution) 7.0-9.0. |
| Key Specifications (Agricultural Grade) | K₂O Content: 50.0%-53.0%; Sulfur (S) Content: 17.0%-18.0%; Chloride (Cl⁻): ≤1.5% (powder premium), ≤2.0% (granular premium), ≤0.5%-0.05% (low-chloride grade); Moisture: ≤1.0%-1.5%; Free Acid (as H₂SO₄): ≤0.1%; Water Insolubles: ≤0.5%. |
| Features | Chloride-Free High Potassium: Safe for all chloride-sensitive crops; Dual Nutrient Source: Provides both potassium (enhances photosynthesis, transport) and sulfur (improves protein content and stress tolerance); Excellent Solubility: Superior to MOP, suitable for drip irrigation, fertigation, and foliar spray; Quality Improvement: Enhances fruit sweetness, color, size, and shelf life during fruit setting and coloring stages; Stress Tolerance: Improves plant resistance to drought, frost, pests, and diseases. |
| Main Applications | I. Agriculture: Ideal potassium and sulfur fertilizer for chlorine-sensitive crops including tobacco, grapes, potatoes, tea, citrus, berries, bananas, vegetables, and ornamentals. Powder/crystalline type is suitable for drip irrigation, fertigation, and hydroponics. Granular type is suitable for broadcasting, drilling, and seed placement. II. Industrial: Used in manufacturing potassium salts, glass clarifiers, dye intermediates, and fragrance auxiliaries. III. Food & Pharmaceutical: Food additive (nutrient fortifier, supplement); pharmaceutical use as laxative. IV. Analytical Reagent: Catalyst in Kjeldahl nitrogen determination; serum potassium testing. |
| Recommended Crops & Application Rates | Fruit Trees (citrus, apple, grapes, banana, cherry): 10-20 kg/mu (150-300 kg/ha) during fruit expansion and coloring stages; Vegetables (tomato, cucumber, pepper, eggplant, beans, watermelon, melon): 10-15 kg/mu (150-225 kg/ha) during mid-late growth stages; Root Crops (potato, sweet potato, sugar beet): For yield levels 22.5-37.5 tons/ha, apply 225-300 kg/ha; Grain Crops (corn, wheat, rice): Apply 150-225 kg/ha as base or top dressing. |
| Application Methods | Base fertilizer (broadcast or band application before plowing), top dressing (band or hole application), seed placement (≤2.5 kg/mu), fertigation (0.5%-1.5% solution), and foliar spray (1%-3% solution). For acidic soils, combine with lime application to prevent acidification. |
| Packaging | 25kg/50kg woven bags (PE liner, paper-plastic composite), 1000kg jumbo bags; food/pharma grade: 25kg kraft paper bags or foil bags; custom packaging available. |
| Storage Conditions | Store in cool, dry, well-ventilated area (below 30℃, RH ≤75%); keep sealed to prevent caking; avoid mixing with acids, alkalis, food, and feed. |
| Shipping Requirements | Non-hazardous cargo; protect from moisture and rain; handle with care to avoid package damage and product loss. |
| Quality Standards | Agricultural Grade: GB/T 20406-2017 (China National Standard for Agricultural Potassium Sulfate). Third-party testing and certifications (ISO 9001, BV, SGS, REACH) available upon request. |
| Minimum Order Quantity | Standard 20-25 tons (1×20'FCL); trial order 5-10 tons (bags) negotiable. |
| Delivery Time | Standard 7-15 working days; custom packaging 15-25 working days. |
| Payment Terms | T/T (30% deposit, 70% against B/L copy); FOB/CFR/CIF supported. |
| HS Code | 3104300000 (Potassium sulfate fertilizer). Declaration elements: package weight, total potassium content, brand, model. Export tariff 0%, export rebate 0%, VAT 9%. Customs supervision condition: 7ABv. |
