Procurement Report: Potassium Hydrogen Sulfate (Hydrogen Sulfate)

Product Category: Inorganic Chemicals / Laboratory Reagents / Industrial Acid Salts Primary CAS: 7646-93-7 Molecular Formula: HKO₄S Molecular Weight: 136.16 g/mol

1. Technical Specifications and Performance Metrics

Potassium Hydrogen Sulfate (KHS), also known as Potassium Bisulfate, is a white crystalline solid that serves as a strong acid source and a fluxing agent. Procurement decisions must prioritize purity grades based on the intended application, as impurities can significantly alter reaction kinetics in analytical or industrial settings.

• Physical State: Solid, typically appearing as white crystals or powder.
• Melting Point: 214°C (Critical for thermal processing applications).
• pH (1% Aqueous Solution): Approximately 1.0 (Indicates strong acidic character).
• Solubility: Highly soluble in water; soluble in glycerol; insoluble in ethanol.
• Purity Grades Available:
  • Reagent Grade (AR): Typical purity ≥ 99.0% to 99.5%.
  • ACS Grade: Purity ≥ 99.0% with strict limits on heavy metals and chloride.
  • Technical Grade: Purity typically ≥ 98.0% (suitable for non-analytical industrial use).
• Packaging Standards: Commonly supplied in high-density polyethylene (HDPE) jars or bottles to prevent moisture absorption. Standard unit sizes include 250 g, 500 g, 1 kg, and bulk 25 kg drums.

Procurement Recommendation: For laboratory analysis, strictly specify "Certified AR" or "ACS Grade" to ensure traceability and low impurity levels. For industrial fluxing or cleaning, Technical Grade is sufficient but requires verification of heavy metal content limits (e.g., Lead < 10 ppm) to prevent catalyst poisoning in downstream processes.

2. Industry Compliance and Quality Assurance

Potassium Hydrogen Sulfate is subject to rigorous quality control standards, particularly when used in analytical chemistry, pharmaceutical synthesis, or food processing. Compliance is verified through specific certification marks and batch testing.

• Certification Standards:
  • Fisher Chemical / Thermo Fisher Scientific: Offers "Certified AR for Analysis," indicating compliance with American Chemical Society (ACS) or equivalent internal standards.
  • ISO 9001: Manufacturers should ideally hold ISO 9001 certification for quality management systems.
  • REACH (EU): Compliance with Registration, Evaluation, Authorisation and Restriction of Chemicals is mandatory for European supply chains.
• Safety Data Sheet (SDS): Must be provided for every batch. The chemical is corrosive and requires PPE (gloves, goggles) handling.
• Traceability: Batch numbers and lot-specific Certificates of Analysis (CoA) are essential for audit trails in regulated industries (e.g., pharmaceuticals).
• Storage Compliance: Must be stored in a cool, dry place away from incompatible materials (bases, water-reactive substances) to prevent deliquescence.

Procurement Recommendation: Require a Certificate of Analysis (CoA) with every shipment. Verify that the CoA includes specific impurity profiles (e.g., Chloride, Sulfate, Heavy Metals) relevant to your application. For EU-based procurement, ensure the supplier provides REACH registration numbers.

3. Cost Efficiency and Integration Capabilities

The cost of Potassium Hydrogen Sulfate varies significantly based on purity, packaging volume, and supplier logistics. It is generally a cost-effective commodity chemical, but bulk purchasing yields substantial savings.

• Typical B2B Pricing Ranges:
  • Laboratory Scale (250g - 1kg): $15.00 – $45.00 per unit (High per-gram cost due to packaging and handling).
  • Industrial Scale (25kg - 200kg): $1.50 – $3.50 per kg (Significant economies of scale).
• Minimum Order Quantity (MOQ):
  • Lab Suppliers: Typically 1 unit (e.g., 250g).
  • Industrial Distributors: Typically 25 kg or 1 pallet.
• Lead Time:
  • In-Stock Items: 1–3 business days (Standard shipping).
  • Bulk/Custom Orders: 2–4 weeks (Dependent on manufacturing capacity).
• Integration Capabilities:
  • Process Integration: Easily integrated into existing acidification or fluxing lines due to its solid state (no pressurized gas or hazardous liquid handling required).
  • Stability: High shelf life (typically 3–5 years) if stored correctly, reducing inventory obsolescence risk.

Procurement Recommendation: Switch from laboratory-sized packaging to bulk drums (25kg+) for any application requiring >5kg per month to reduce cost per unit by up to 60%. Negotiate volume discounts for recurring annual contracts. Ensure warehouse storage conditions (humidity control) are verified to prevent clumping, which can affect dosing accuracy.

4. Typical Use Cases

Potassium Hydrogen Sulfate is versatile across multiple sectors due to its dual role as an acid source and a fluxing agent.

• Analytical Chemistry: Used as a primary standard or flux for digesting refractory ores and minerals.
• Water Treatment: Employed as a pH adjuster and in the regeneration of ion exchange resins.
• Industrial Cleaning: A key ingredient in toilet bowl cleaners and rust removers due to its ability to dissolve mineral deposits.
• Metallurgy: Acts as a flux in soldering and brazing to remove oxide layers from metal surfaces.
• Food Industry: Used as a leavening agent in baking powders (often in combination with sodium bicarbonate) and as an acidity regulator.
• Pharmaceuticals: Used as an intermediate in the synthesis of various organic compounds and as a buffer component.

Procurement Recommendation: Match the grade to the use case. Do not use Technical Grade for food or pharmaceutical applications; strictly require Food Grade or USP/EP certification. For analytical digestion, ensure the product is free from chloride ions if analyzing for chloride content.

5. Long-Term Planning Considerations

The market for Potassium Hydrogen Sulfate is stable, driven by consistent demand in industrial cleaning and water treatment. However, supply chain resilience and sustainability are becoming critical factors.

• Market Trends:
  • Shift to Green Chemistry: Increasing demand for "cleaner" fluxing agents that produce fewer hazardous byproducts compared to traditional strong acids.
  • Supply Chain Consolidation: Major chemical manufacturers are consolidating production, leading to fewer but larger suppliers.
  • Regulatory Pressure: Stricter regulations on sulfur emissions and wastewater discharge may increase demand for KHS as a more manageable alternative to liquid sulfuric acid.
• Demand Signals:
  • Steady growth in the water treatment sector (infrastructure upgrades).
  • Consistent demand in the electronics industry for PCB cleaning and etching.
• Risk Factors:
  • Raw Material Volatility: Fluctuations in the price of sulfuric acid and potassium hydroxide (feedstocks) can impact KHS pricing.
  • Logistics: As a solid, it is safer to transport than liquid acids, but moisture sensitivity requires specialized packaging logistics.

Procurement Recommendation: Develop a dual-sourcing strategy to mitigate supply chain disruptions. Consider long-term contracts with suppliers who demonstrate robust sustainability practices (e.g., energy-efficient manufacturing). Monitor global sulfur prices as a leading indicator for raw material cost adjustments.

6. Special Product Recommendations

The following table compares available product types to assist in selecting the optimal procurement option based on buyer profile and risk tolerance.

| Product Type | Best-Fit Buyer | Key Specs | Risk Check | Procurement Advice | | :--- | :--- | :--- | :--- :--- | | Certified AR / ACS Grade | Research Labs, QA/QC, Pharma | Purity ≥ 99.0%, Low heavy metals, Batch CoA | Low (High Traceability) | Purchase from established distributors (e.g., Thermo Fisher) for guaranteed purity. | | Technical Grade | Industrial Cleaning, Water Treatment | Purity ≥ 98.0%, Bulk packaging (25kg+) | Medium (Variable Impurities) | Request specific impurity limits (e.g., Chloride < 0.05%) before ordering. | | Food Grade | Food Processing, Baking | Compliant with FDA/EFSA, No heavy metals | Low (Regulatory Compliance) | Verify specific food additive codes (e.g., E514) on the CoA. | | Bulk Drum (200kg) | Large-Scale Manufacturing | Cost-effective, Standardized packaging | Medium (Moisture Control) | Ensure warehouse has dehumidification capabilities to prevent clumping. |

Procurement Recommendation: For high-volume industrial users, prioritize Technical Grade in bulk drums to maximize cost efficiency. For any application involving human health or precise scientific measurement, the Certified AR grade is non-negotiable despite the higher unit cost.

7. Frequently Asked Questions (FAQ)

Q1: What is the difference between Potassium Hydrogen Sulfate and Potassium Sulfate? A: Potassium Hydrogen Sulfate (KHS) is an acid salt (monopotassium salt) with a pH of ~1 in solution, acting as a strong acid. Potassium Sulfate (K₂SO₄) is a neutral salt with a pH near 7. They are not interchangeable in acidification applications.

Q2: Is Potassium Hydrogen Sulfate safe to handle? A: It is corrosive. It can cause severe skin and eye burns. Procurement must include a Safety Data Sheet (SDS), and staff must be trained to use appropriate PPE (gloves, goggles, lab coats).

Q3: How should this chemical be stored to maintain quality? A: Store in a cool, dry place in tightly sealed containers. It is hygroscopic and can absorb moisture from the air, leading to clumping or degradation. Keep away from bases and water-reactive substances.

Q4: Can I use Technical Grade for analytical titration? A: No. Technical Grade may contain impurities that interfere with titration results. Always use Certified AR or ACS Grade for analytical applications to ensure accuracy.

Q5: What is the typical shelf life of Potassium Hydrogen Sulfate? A: When stored properly in sealed containers, it has a shelf life of 3 to 5 years. However, once opened, it should be used within 12 months to prevent moisture absorption.

Q6: Is this product suitable for food applications? A: Only if specifically certified as "Food Grade" or compliant with relevant food safety regulations (e.g., FDA, EFSA). Standard laboratory or technical grades are not approved for food use.

Q7: What packaging options are available for bulk orders? A: Common options include 250g/500g plastic jars for labs, 1kg bottles, and 25kg or 200kg HDPE drums or fiber drums for industrial use.

Q8: How does the melting point affect its industrial use? A: With a melting point of 214°C, it is suitable for high-temperature fluxing applications where it can melt to form a liquid slag, but it remains stable at standard room temperatures, simplifying storage.