Zhuochi AOX-3 Adsorbable Organic Halogens (AOX) Combustion Furnace

Overview

The Zhuochi AOX-3 Adsorbable Organic Halogens (AOX) Combustion Furnace is a dedicated high-temperature thermal oxidation system engineered for the quantitative determination of adsorbable organic halogens in environmental matrices. It operates on the internationally recognized principle of high-temperature combustion (up to 1150 °C) followed by halogen-specific detection—either via microcoulometric titration or ion chromatography—per established regulatory protocols. The instrument implements the column adsorption method: organic halogens in aqueous or solid samples are first concentrated onto activated carbon (or packed carbon columns), then thermally desorbed and combusted under controlled oxygen flow. Resulting halide ions (Cl⁻, Br⁻, F⁻, I⁻) are absorbed into an alkaline solution and quantified downstream using complementary analytical instrumentation (e.g., microcoulometer or IC system). Designed for compliance-driven laboratories, the AOX-3 supports full traceability and reproducibility in routine AOX monitoring across water, wastewater, sludge, soil, and industrial effluents.

Key Features

• Programmable temperature control with LTDE PID + SSR regulation, enabling precise ramp/soak profiles and automated sequence execution
• Ceramic fiber furnace chamber (φ40 × 300 mm) with dual semi-cylindrical construction, embedded high-resistance heating wire, and air-cooled metal housing for thermal efficiency and safety
• Fast thermal response: <10 min startup time; adjustable heating rate up to 50 °C/min with ±1 °C temperature stability
• Front-access, hinged furnace design permitting real-time visual monitoring of sample combustion and carrier tube status
• Integrated built-in scrubbing system with five dedicated wash bottles and two absorption units, minimizing cross-contamination and ensuring gas purity
• Low-voltage high-efficiency heating architecture (220 V, 1.5 kW) optimized for extended unattended operation—validated for continuous 24-hour duty cycles
• Dual-stage overtemperature protection with independent thermal cutoffs, conforming to IEC 61000-4-2 and general lab safety requirements
• Modular gas handling interface supporting both compressed nitrogen (for pressurized adsorption) and high-purity oxygen (≥99.999%) for clean combustion

Sample Compatibility & Compliance

The AOX-3 accommodates diverse sample types per HJ/T 83–2001 and ISO 9562:1989, including drinking water, surface water, groundwater, municipal and industrial wastewater, leachates, saline water, pulp mill effluents, sediments, sludges, soils, and waste oils. Sample introduction employs standardized activated carbon adsorption—either via disposable sample boats or fixed-bed adsorption columns—with optional ultrasonic-assisted enrichment recommended for enhanced recovery. All operational parameters—including combustion temperature, gas flow rates, and adsorption dwell time—are fully configurable to meet matrix-specific optimization needs. The system is validated for adherence to multiple regulatory frameworks: HJ/T 83–2001 (China EPA), ISO 9562:1989 (International Organization for Standardization), GB/T 15959–1995 (Chinese National Standard), and supplementary discharge standards GB 8978–1996 and GB 3544–2008. While the furnace itself does not generate final quantitative reports, its output is fully compatible with GLP-compliant data acquisition systems when interfaced with certified microcoulometers or ion chromatographs meeting USP , ASTM D5908, and EPA Method 1650 requirements.

Software & Data Management

The AOX-3 operates as a hardware platform requiring external analytical instrumentation for final quantification. Optional PC-based control software (sold separately) provides real-time temperature logging, programmable method storage (up to 16 user-defined profiles), and CSV-exportable thermal history files compliant with 21 CFR Part 11 audit trail requirements. When integrated with validated third-party coulometric or IC systems, the complete workflow supports electronic signatures, user access levels, and raw data archiving aligned with ISO/IEC 17025 accreditation criteria. No proprietary firmware or closed-loop automation is embedded—the design prioritizes interoperability, serviceability, and long-term calibration transparency over black-box operation.

Applications

• Regulatory compliance testing for AOX in municipal wastewater treatment plants (WWTPs) and industrial dischargers subject to EU Directive 2013/39/EU or China’s “Water Pollution Prevention and Control Action Plan”
• Monitoring chlorinated disinfection byproducts (DBPs) in drinking water distribution networks
• Assessing halogenated organic load in pulp and paper mill effluents prior to biological treatment
• Characterizing halogenated contaminants in landfill leachate and contaminated site soils
• Supporting environmental impact assessments (EIAs) and permit renewal submissions requiring AOX mass balance calculations
• Method development and validation studies in accredited environmental testing laboratories (CNAS, ILAC-MRA signatory labs)

FAQ

What detection methods are compatible with the AOX-3 furnace?
The AOX-3 is designed for coupling with either microcoulometric titration systems (per GB/T 15959–1995) or ion chromatography (per HJ/T 83–2001). It does not include an integrated detector.

Is purified oxygen required for optimal performance?
Yes. Use of ultra-high-purity oxygen (≥99.999%) eliminates the need for auxiliary gas scrubbing and improves combustion completeness and halogen recovery—particularly critical for low-level (<10 µg/L) measurements.

Can the AOX-3 process solid samples directly?
Solid matrices (e.g., soils, sludges) must first undergo solvent extraction and pre-concentration on activated carbon. The furnace accepts only carbon-loaded samples—either in quartz boats or packed adsorption columns.

Does the system support automated sample throughput?
No. The AOX-3 is a single-position furnace intended for sequential manual analysis. High-throughput labs typically deploy multiple units or integrate with autosampler-compatible carbon column manifolds (not supplied).

What maintenance intervals are recommended?
Ceramic insulation and heating elements require no scheduled replacement under normal use. Quarterly inspection of gas tubing, absorption vessels, and O-rings—and annual calibration of the K-type thermocouple against NIST-traceable reference—is advised per ISO/IEC 17025 Clause 6.4.