HEXING BIOCHEMICAL HXN-W20 Multi-Channel Microwave Evaporation and Ashing System for Radiochemical α/β Sample Preparation

Overview

The HEXING BIOCHEMICAL HXN-W20 Multi-Channel Microwave Evaporation and Ashing System is an engineered solution for radiochemical sample preparation in environmental and nuclear laboratories. It integrates two thermally distinct but sequentially critical unit operations—microwave-assisted liquid evaporation and high-temperature oxidative ashing—into a single, modular platform. Unlike conventional hotplate evaporation followed by separate muffle furnace ashing, the HXN-W20 employs dielectric microwave heating to directly couple energy into aqueous samples and residual solids, enabling rapid, uniform thermal processing without conductive heat transfer limitations. This principle supports controlled boiling during concentration and efficient carbonization/ashing of organic matrices under oxidizing conditions—critical for quantitative recovery of α- and β-emitting radionuclides (e.g., ²¹⁰Po, ⁹⁰Sr, ²⁴¹Am) from large-volume water matrices. Designed for compliance with regulatory workflows defined in ISO 10703, ASTM D5098, and Chinese national standards including GB/T 5750.13–2006 and GB 5749–2006, the system serves as a validated alternative to legacy open-vessel digestion and furnace-based residue treatment.

Key Features

• Patented dual-cavity architecture: Independent microwave-evaporation and microwave-ashing chambers operate at optimized power levels (up to 3200 W for evaporation; 800 W for ashing), each with dedicated frequency-stable 2450 MHz magnetron sources and waveguide coupling.
• Multi-channel scalability: Configurable as single-channel (HXN-W20L-11), dual-channel (HXN-W20T-21), or quad-channel (HXN-W20S-41) systems—each evaporation cavity holds up to 24 L volume capacity, supporting parallel processing of up to four 2.9 L PTFE-coated quartz evaporating dishes (customizable up to 10 L).
• Corrosion-resistant construction: Evaporation chamber interior lined with industrial-grade PTFE coating; ashing chamber features fused-quartz inner lining and stainless-steel welded monocoque housing compliant with GB 5959.6–2008 for industrial microwave equipment safety.
• Precision thermal management: Non-contact infrared pyrometry for real-time surface temperature monitoring during evaporation; calibrated K-type thermocouples embedded in ashing chamber floor for accurate solid-phase temperature control (0–300 °C, ±0.1 °C stability).
• Integrated exhaust and containment: Low-noise (<60 dB(A)) corrosion-resistant centrifugal blower with directional vapor extraction, coupled with sealed observation windows and internal LED illumination for process verification without interruption.
• Industrial-grade PLC control: Touchscreen HMI with preloaded method templates for EPA 900-series, GB/T 5750.13, and custom protocols; full parameter logging (time, power, temperature, cavity status); data export via USB or RS485 to LIMS-compatible formats.

Sample Compatibility & Compliance

The HXN-W20 accommodates acidic (HNO₃, HCl, H₂SO₄-digested), alkaline, and saline aqueous matrices—including drinking water, groundwater, surface water, wastewater, precipitation, and air particulate leachates. Its PTFE-coated evaporating dishes and quartz-lined ashing chamber ensure compatibility with aggressive acid residues post-digestion. The system meets electromagnetic safety requirements per GB 4706.21–2008 and GB 5959.6–2008, with verified microwave leakage <5 mW/cm² at 5 cm distance. It supports GLP-aligned operation through audit-trail-capable data storage, user-access-level controls, and method versioning—enabling traceability required for CNAS-accredited labs and regulatory submissions to NNSA, CDC, and provincial radiation monitoring centers.

Software & Data Management

The embedded PLC controller runs HEXING’s proprietary EvapAsh™ firmware, providing multi-stage programmable sequences (e.g., ramp-hold-evaporate-dry-ash-cool). All operational parameters—including time stamps, setpoints, actual temperatures, power output, and door interlock status—are timestamped and stored internally (≥10,000 cycles). Data export is supported in CSV format via USB port; optional Modbus TCP integration allows remote monitoring in centralized lab automation environments. Firmware updates are performed offline via secure SD card, preserving configuration integrity across revisions. No cloud connectivity or external telemetry is implemented—ensuring data sovereignty for radiological laboratories handling sensitive environmental surveillance data.

Applications

• Pre-concentration and ashing of large-volume (up to 24 L) water samples prior to α-spectrometry (²³⁴U, ²³⁸U, ²³⁹Pu) and liquid scintillation counting (LSC) of ⁹⁰Sr/⁹⁰Y and ²¹⁰Pb.
• Routine analysis of gross α/β activity in compliance with GB/T 5750.13–2006, ISO 10703:2021, and IAEA Technical Reports Series No. 488.
• Radiochemical separation workflows involving Fe(OH)₃ or MnO₂ co-precipitation, where rapid matrix removal and ash yield consistency are essential.
• Research-scale development of novel radionuclide recovery methods, including solvent extraction feedstock preparation and cerium oxide target synthesis requiring low-impurity carbon-free residues.
• Emergency response labs performing accelerated screening of post-incident environmental samples under time-constrained QA/QC protocols.

FAQ

Can the HXN-W20 handle HF-containing digestates?

No. Hydrofluoric acid is incompatible with both PTFE-coated evaporating dishes and quartz ashing chambers. Samples requiring HF digestion must be fully neutralized and diluted prior to loading.

Is method validation support available?

Yes. HEXING provides application notes aligned with GB/T 5750.13–2006 and ASTM D5098, including spike recovery data, blank assessment protocols, and precision studies across 10–24,000 mL volume ranges.

What maintenance intervals are recommended for continuous operation?

Evaporator waveguide filters require cleaning every 200 operating hours; magnetron cooling fans inspected quarterly; PTFE dish surfaces assessed for micro-pitting semi-annually. Full calibration of IR and thermocouple sensors is advised annually per ISO/IEC 17025.

Does the system comply with FDA 21 CFR Part 11 requirements?

While not certified for pharmaceutical GMP, the HXN-W20 supports Part 11–aligned practices via electronic signature-enabled method locking, audit trail generation, and role-based access control—suitable for regulated environmental testing labs adopting ALCOA+ data integrity principles.

Can ashing be performed without prior evaporation on the same instrument?

Yes. The ashing chamber operates independently; users may load pre-dried or oven-dried residues directly into the 1.8 L quartz chamber for controlled oxidative ashing at temperatures up to 300 °C.