Honeywell HLN-500P High-Purity Nitrogen Generator

Overview

The Honeywell HLN-500P is a membrane-assisted pressure-swing electrolytic nitrogen generator engineered for continuous, on-demand production of ultra-high-purity nitrogen gas (≥99.999%) in analytical laboratory environments. Unlike compressed-air-fed PSA or hollow-fiber membrane systems, the HLN-500P employs a dual-cathode stainless-steel alkaline electrolytic cell architecture—operating on the principle of water electrolysis—to separate oxygen and hydrogen from deionized water feedstock, delivering nitrogen enriched via selective electrochemical oxygen removal and catalytic recombination. This process eliminates reliance on external nitrogen cylinders, reduces logistical overhead, and ensures consistent gas quality critical for sensitive applications including GC carrier gas, LC-MS purge gas, sample preparation inerting, and glovebox purging. The system integrates thermal management, real-time pressure regulation, and fail-safe shutdown logic to maintain operational integrity under variable load conditions.

Key Features

• Dual-cathode stainless-steel electrolytic cell with enlarged electrode surface area—enhances gas yield while maintaining low operating temperature (<45 °C), minimizing thermal drift and extending electrolyte service life.
• Patented anti-backflow liquid trap and gravity-assisted electrolyte circulation design—prevents electrolyte carryover into the gas stream, eliminating risk of instrument contamination or downstream valve fouling.
• Integrated pressure regulation and automatic shut-off circuitry—maintains stable output pressure (factory-calibrated at 0.4 MPa, adjustable up to 0.5 MPa) and severs gas flow within 2 seconds of power loss or overpressure event.
• High-efficiency switched-mode power supply (SMPS)—optimized for electrolytic current density control, improving energy conversion efficiency by ≥18% compared to legacy linear power topologies.
• Compact benchtop footprint (W × D × H: 260 × 420 × 380 mm) and lightweight aluminum-chassis construction—designed for space-constrained labs and mobile analytical platforms without compromising structural rigidity.

Sample Compatibility & Compliance

The HLN-500P delivers nitrogen meeting ASTM D6866-22 specifications for isotopic purity and ISO 8573-1:2010 Class 1 compressed air quality equivalency (when used with optional in-line particulate and hydrocarbon filters). It is compatible with all standard 1/8″ and 1/4″ stainless-steel or PTFE gas lines and supports integration into existing lab gas distribution networks via NPT or Swagelok fittings. The unit complies with IEC 61010-1:2010 for electrical safety in laboratory equipment and meets CE marking requirements for EMC immunity (EN 61326-1) and conducted emissions (EN 55011). While not certified for hazardous-area operation, its sealed electrolytic core and non-sparking controls render it suitable for general-purpose analytical labs operating under GLP and ISO/IEC 17025 frameworks.

Software & Data Management

The HLN-500P operates as a standalone analog-controlled system with no embedded firmware or digital interface. All operational parameters—including output pressure, flow rate, and cell voltage—are monitored via front-panel analog gauges and LED status indicators. For laboratories requiring audit-ready records, optional analog-to-digital signal converters (e.g., Honeywell X-Series DAQ modules) enable integration with LabVantage, Empower, or custom SCADA systems. Raw sensor outputs support 4–20 mA or 0–10 V analog logging, enabling full traceability per FDA 21 CFR Part 11 when paired with validated electronic lab notebooks (ELNs) and time-stamped data acquisition software. No internal storage or cloud connectivity is implemented—ensuring data sovereignty and simplifying 21 CFR Part 11 compliance validation.

Applications

• Carrier gas for capillary gas chromatography (GC), particularly in ECD, TCD, and FID configurations requiring oxygen-free, moisture-free nitrogen.
• Purge and trap gas for volatile organic compound (VOC) analysis, where residual O₂ or H₂O would compromise adsorbent tube integrity or detector baseline stability.
• Inert atmosphere generation for solvent evaporation stations, nitrogen blow-down concentrators, and Schlenk line auxiliary supply.
• Blank gas for FTIR gas cell calibration and Raman spectroscopy background subtraction.
• Supply gas for elemental analyzers (CHNS/O), thermal gravimetric analyzers (TGA), and differential scanning calorimeters (DSC) requiring high-purity purge streams.

FAQ

What feedwater quality is required for optimal operation?
Deionized water with resistivity ≥15 MΩ·cm and total organic carbon (TOC) < 10 ppb is mandatory. Tap water or distilled water will cause rapid electrode passivation and irreversible cell degradation.
Does the HLN-500P require periodic electrolyte replacement?
No—the system uses a closed-loop, recirculating KOH-based electrolyte solution. Under normal operation and proper feedwater quality, electrolyte replenishment is not required for ≥12 months; visual inspection and conductivity verification are recommended quarterly.
Can output pressure be adjusted beyond the factory setting of 0.4 MPa?
Yes—via the integrated precision pressure regulator. However, sustained operation above 0.45 MPa may reduce long-term seal integrity and is not covered under warranty unless validated with Honeywell Field Service.
Is the nitrogen output suitable for use with mass spectrometry systems?
Yes—provided the optional 0.01 µm coalescing filter and activated carbon scrubber are installed upstream. Residual hydrogen (<1 ppm) and oxygen (<0.1 ppm) levels meet OEM requirements for most quadrupole and triple-quadrupole MS instruments.
How does ambient humidity affect performance?
Relative humidity outside the 30–70% range may impact front-panel display contrast and switch contact reliability but has no measurable effect on gas purity or flow stability due to fully sealed internal gas pathways.