Mitsubishi Chemical CA-200 Coulometric Karl Fischer Moisture Analyzer
| Brand | Mitsubishi Chemical |
|---|---|
| Origin | Japan |
| Model | CA-200 |
| Measurement Principle | Coulometric Karl Fischer Titration |
| Moisture Range | 10 µg – 100 mg H₂O |
| Precision | CV ≤ 0.3% for samples ≥ 1 mg (n = 10) |
| Minimum Dispensing Volume | 1/2000 of burette volume |
| Electrolysis Current | 430 mA |
| Average Titration Speed | 2.2 mg H₂O/min (36 µg/sec) |
| Display | 5.7-inch color LCD |
| Data Storage | 20 user-defined methods × 50 sub-files each |
| Compliance | GLP/GMP-ready with audit trail support (via optional RS-232C or USB export) |
| Optional Accessories | VG-200 gas vaporization unit, membrane/no-membrane generator electrodes, reagent dispensing module |
Overview
The Mitsubishi Chemical CA-200 is a high-precision coulometric Karl Fischer moisture analyzer engineered for trace to macro-level water quantification in challenging non-aqueous matrices—particularly liquefied gases, compressed gases, and volatile organic compounds. Unlike volumetric KF systems, the CA-200 employs controlled electrolytic generation of iodine at the anode, enabling direct stoichiometric quantification of water according to the classical Karl Fischer reaction: H₂O + I₂ + SO₂ + 3RN + CH₃OH → 2RN·HI + RN·HSO₄CH₃. This coulometric architecture eliminates burette calibration drift and delivers exceptional reproducibility across the full 10 µg–100 mg H₂O measurement range. When paired with the optional VG-200 gas vaporization unit, the system forms a fully integrated solution for regulated moisture analysis in pressurized gaseous samples—including LPG, LNG, refrigerants (CFCs, HFCs, HCFCs), ethylene oxide, vinyl chloride, and chloromethanes—without manual syringe heating or operator-dependent vaporization steps.
Key Features
- Dual-channel expandability: Supports concurrent operation of two independent titration cells, two generator electrodes, or two vaporization units—enabling parallel sample analysis or method validation without hardware duplication.
- Intelligent electrode maintenance: Automatic polarization and cleaning cycles eliminate manual electrode polishing; real-time current monitoring detects and compensates for electrode fouling during titration.
- Five-speed magnetic stirrer: Precision-controlled stirring (5 adjustable levels) ensures homogeneous mixing and stable endpoint detection—even for low-conductivity gas-derived condensates.
- Modular reagent management: Optional reagent dispensing module enables one-touch evacuation of spent electrolyte and automated refilling—reducing exposure risk and cross-contamination between runs.
- Open calculation framework: Users define custom calculation formulas (e.g., ppm, wt%, mol%, normalized to gas volume or mass) directly in the instrument firmware; results are computed and displayed automatically post-titration.
- GLP-compliant data integrity: Built-in timestamped audit trail (with optional RS-232C or USB logging) records method parameters, operator ID, cell status, titration curves, and raw coulombic integrals—fully traceable for FDA 21 CFR Part 11 and ISO/IEC 17025 compliance.
- Flexible electrode selection: Interchangeable membrane and membrane-free generator electrodes accommodate diverse sample chemistries—membrane electrodes enable accurate analysis of ketones, aldehydes, and low-hydroxyl acids; membrane-free variants simplify maintenance for routine hydrocarbon testing using AQUAMICRON single-solution reagents.
Sample Compatibility & Compliance
The CA-200, especially when coupled with the VG-200 vaporization module, meets stringent industry requirements for moisture determination in gaseous and liquefied petroleum products. It complies with ASTM D6304 (Standard Test Method for Determination of Water in Petroleum Products, Lubricating Oils, and Additives by Coulometric Karl Fischer Titration), ISO 15512 (Plastics — Determination of water content), and JIS K 0070 (Chemical reagents — Determination of water). Its validated performance for ppb–ppm level moisture in pressurized systems (up to 1 MPa) supports quality control in refrigerant manufacturing, petrochemical refining, semiconductor process gas supply, and pharmaceutical propellant production. The system’s closed-loop gas handling, temperature-stabilized vaporization (40–90 °C), and flow-controlled injection (100–600 mL/min) ensure representative sampling and minimize adsorption losses—critical for regulatory submissions under ICH Q5C and USP .
Software & Data Management
The CA-200 features an embedded operating system with a 5.7-inch color TFT-LCD interface supporting multilingual menus (English, Japanese, Chinese). All method parameters—including gas-specific flow conversion coefficients, titration thresholds, stirring speed, and endpoint delay—are stored in 20 customizable method files (each holding up to 50 sub-methods). Raw coulombic integrals, titration curves, and calculated results are exportable via USB mass storage or RS-232C (optional) to LIMS or ELN platforms. Internal memory retains 200 complete test records with full metadata: date/time, operator ID, sample ID, method name, weight/mass/volume input (auto-imported from connected analytical balances), and statistical summaries (mean, SD, CV). Audit logs capture all parameter changes and reagent replacement events—essential for GMP laboratory inspections.
Applications
- Quantification of water in liquefied petroleum gas (LPG), propane, butane, propylene, and butadiene per ASTM D6304 Annex A3.
- Moisture verification in refrigerant blends (R-134a, R-410A, R-32, R-1234yf) prior to cylinder filling—ensuring dew point compliance and compressor safety.
- Trace water analysis in ethylene oxide sterilization gases and vinyl chloride monomer (VCM) feedstocks—critical for polymerization catalyst protection.
- Quality release testing of specialty gases (e.g., SF₆, silane, arsine) used in semiconductor fabrication.
- Stability-indicating moisture monitoring in chlorinated solvents (chloromethane, chloroform) and ether-based extraction media.
- Batch-to-batch consistency verification for formulated propellants and inhalation aerosols in pharmaceutical manufacturing.
FAQ
What sample types can the CA-200 analyze without the VG-200?
The base CA-200 analyzer accepts liquids, solids, and soluble powders via direct injection or oven coupling. It is not designed for direct gas-phase injection without vaporization support.
Is the VG-200 compatible with corrosive gases like chlorine or hydrogen sulfide?
No—the VG-200 wetted materials (stainless steel 316, PTFE, FKM) are rated for hydrocarbons, halogenated refrigerants, and oxygenates. Corrosive or oxidizing gases require custom inlet conditioning and are outside standard validation scope.
Can the CA-200 meet FDA 21 CFR Part 11 requirements?
Yes—when configured with password-protected user roles, electronic signatures (via external PC software), and full audit-trail logging (enabled via RS-232C or USB), it satisfies electronic record and signature criteria for regulated environments.
What is the typical service life of the generator electrode?
Under normal use with AQUAMICRON reagents and proper maintenance, the no-membrane electrode lasts ≥12 months; membrane electrodes typically require replacement every 6–9 months depending on sample matrix aggressiveness.
Does the system support automatic blank correction?
Yes—built-in drift compensation continuously monitors background electrolysis current and subtracts baseline contribution from final water calculation, improving accuracy for ultra-low moisture (<50 µg) determinations.
