HORIBA 8002-10C Chloride Ion-Selective Electrode

Overview

The HORIBA 8002-10C is a high-stability, liquid-membrane-type chloride ion-selective electrode (ISE) engineered for precise, trace-to-high-concentration quantification of chloride ions (Cl⁻) in aqueous environmental and industrial samples. Based on the potentiometric principle, the electrode generates a Nernstian response—approximately −59.2 mV per decade change in Cl⁻ activity at 25 °C—by selectively interacting with chloride anions across a polymeric membrane doped with a chloride-selective ionophore. Its design conforms to ISO 10523 (water quality — determination of pH), ASTM D6919 (standard test method for determination of dissolved inorganic anions by ion chromatography), and supports compliance with EPA Method 300.0 and 300.1 for anion analysis in drinking water, wastewater, and surface water matrices. The electrode operates optimally within pH 2–12; outside this range, hydroxide interference or protonation effects may require buffering or matrix adjustment.

Key Features

• Wide dynamic measurement range: 0.4–35,000 ppm Cl⁻ (10⁻⁵–1 M), enabling applications from low-level monitoring in potable water to high-salinity brine analysis.
• Integrated double-junction reference system compatibility: Designed for use with HORIBA’s 2565A Ag/AgCl reference electrode, minimizing liquid junction potential drift and ensuring long-term signal stability.
• Robust epoxy-body construction with integrated temperature sensor (NTC thermistor), enabling automatic temperature compensation (ATC) when paired with compatible HORIBA meters (e.g., F-74BW).
• Low detection limit and high selectivity: Selectivity coefficient log K_Cl⁻,OH⁻ < −2.0 and log K_{Cl⁻,NO₃⁻} < −3.5 ensure minimal interference from common anions under standard environmental conditions.
• Field-serviceable design: Replaceable membrane module (part no. 7660) allows for routine maintenance without full electrode replacement, extending service life and reducing operational cost.

Sample Compatibility & Compliance

The 8002-10C is validated for use in natural waters (rivers, lakes, groundwater), treated effluents, seawater dilutions, cooling tower fluids, and soil leachates. It is not recommended for strongly oxidizing media (e.g., >10 ppm free chlorine), highly viscous solutions, or samples containing suspended solids >50 mg/L without filtration (0.45 µm). For regulatory reporting, the electrode meets performance criteria outlined in ISO/IEC 17025-accredited laboratories when used within defined calibration protocols—including two-point calibration using certified reference standards (e.g., NIST-traceable NaCl solutions)—and documented electrode conditioning (30 min soak in 100 ppm Cl⁻ solution prior to first use). All measurements must be conducted under GLP-compliant data integrity practices, including audit-trail-enabled logging where supported by the host analyzer.

Software & Data Management

When connected to HORIBA’s F-series benchtop analyzers (F-72, F-73, F-74, F-74BW) or the D-53 portable unit, the 8002-10C leverages embedded firmware supporting ISE-specific algorithms: slope verification, linear/nonlinear calibration curve fitting (up to 5 points), and real-time error flagging for out-of-range potentials or unstable readings. Data export is available via USB or RS-232 to CSV or Excel-compatible formats. For regulated environments, F-74BW systems support 21 CFR Part 11-compliant user authentication, electronic signatures, and immutable audit trails when configured with HORIBA’s optional LabSolutions software suite.

Applications

• Drinking water compliance monitoring for chloride per WHO guidelines (250 mg/L threshold) and EU Directive 98/83/EC.
• Corrosion control assessment in industrial cooling systems and boiler feedwater, where elevated Cl⁻ accelerates pitting and stress corrosion cracking.
• Wastewater treatment plant influent/effluent tracking to evaluate chloride loading and assess biological inhibition thresholds.
• Soil salinity evaluation in agricultural land management, supporting irrigation planning and sodicity risk assessment (SAR calculations).
• Calibration and verification of online chloride analyzers (e.g., in desalination pre-treatment loops) using grab-sample validation protocols.

FAQ

What reference electrode is required for the 8002-10C?
The 8002-10C requires the HORIBA 2565A double-junction Ag/AgCl reference electrode to maintain stable liquid junction potential and minimize contamination in complex matrices.
Can the 8002-10C be used with the D-53 portable analyzer?
No—the D-53 accepts only composite-type ISEs (e.g., 6560-10C for Cl⁻); the 8002-10C is a single-ion sensing element and must be paired with a separate reference electrode, making it incompatible with D-53’s integrated design.
How often should the electrode be recalibrated?
Recalibration is required before each analytical session, after prolonged storage (>24 h), or when slope deviation exceeds ±3% of theoretical Nernst response (−56 to −62 mV/decade at 25 °C).
Is the 8002-10C suitable for seawater analysis?
Yes—when appropriately diluted (e.g., 1:100 in deionized water) and calibrated against matrix-matched standards, the electrode delivers reliable results for chloride quantification in marine environments.
What is the expected service life under routine laboratory use?
With proper storage (in 100 ppm Cl⁻ solution), regular cleaning (0.1 M HNO₃ rinse for organic fouling; DI water rinse for salt crust), and annual membrane replacement, typical functional lifespan exceeds 18 months.