Zhonghui Pu SPH-300MT Automatic Makeup Alkaline Electrolysis Hydrogen Generator

Overview

The Zhonghui Pu SPH-300MT is a compact, benchtop hydrogen generator engineered for continuous, on-demand supply of high-purity hydrogen gas in analytical laboratory environments—particularly as a carrier or fuel gas for gas chromatography (GC), GC–MS, and other instrumentation requiring stable, low-flow H₂. It employs aqueous alkaline electrolysis of deionized water using a potassium hydroxide (KOH) electrolyte solution to split water molecules into hydrogen and oxygen at the cathode and anode, respectively. The system integrates a sealed, corrosion-resistant electrolytic cell with a proprietary gas–liquid separation chamber and palladium-silver alloy membrane-based purification, enabling consistent delivery of 99.999% pure hydrogen without external cylinders. Unlike PEM-based generators, this design avoids expensive noble-metal catalysts while maintaining robust performance under variable load conditions typical of GC oven ramping and detector switching.

Key Features

• Intelligent microcontroller-based control system enabling fully automatic operation—including real-time flow monitoring, dynamic flow modulation based on downstream demand, and self-initiated electrolyte makeup via integrated level-sensing reservoir.
• Hermetically sealed internal architecture minimizes operator exposure to caustic KOH electrolyte and eliminates risk of leakage or aerosol formation during operation or maintenance.
• Multi-layer safety architecture: pressure-relief valve, over-pressure cut-off (< 0.42 MPa), flow-limiting interlock, thermal shutdown (≥ 85°C), and dry-run protection prevent hazardous operational states.
• Stable pressure regulation with ≤ 0.001 MPa fluctuation across full flow range (0–300 mL/min), critical for retention time reproducibility in capillary GC applications.
• Low power draw (150 W nominal) and passive cooling design support unattended 24/7 operation in standard laboratory environments without auxiliary ventilation or HVAC load compensation.

Sample Compatibility & Compliance

The SPH-300MT delivers hydrogen suitable for all GC configurations requiring ultra-high purity carrier gas—including flame ionization detectors (FID), thermal conductivity detectors (TCD), and electron capture detectors (ECD). Its 99.999% purity meets ASTM D7165–22 specifications for instrumental gas quality and satisfies baseline requirements for USP , ISO/IEC 17025, and GLP-compliant laboratories. While not certified to UL/CSA or CE for standalone safety marking, its electrical design conforms to IEC 61010-1:2010 (Safety Requirements for Electrical Equipment for Measurement, Control, and Laboratory Use). All wetted materials—including 316L stainless steel manifolds, EPDM diaphragms, and nickel-plated electrodes—are compatible with alkaline electrolyte and resistant to hydrogen embrittlement.

Software & Data Management

The unit operates autonomously without external software; however, digital LED interface provides real-time display of output pressure (MPa), actual flow rate (mL/min), operating temperature (°C), and system status codes. Optional RS-232 or analog 0–5 V output (available upon request) enables integration into centralized lab monitoring systems supporting Modbus RTU or LabVIEW-compatible protocols. Audit trails—including runtime hours, total gas volume generated, and fault event logs—are stored locally in non-volatile memory and retrievable via serial query, supporting FDA 21 CFR Part 11-aligned data integrity practices when paired with validated third-party acquisition software.

Applications

• Carrier gas source for capillary gas chromatography, especially in environmental, pharmaceutical, and petrochemical QA/QC labs where cylinder logistics pose contamination or scheduling risks.
• Fuel gas supply for FID and NPD detectors requiring precise stoichiometric H₂:air ratios.
• Hydrogen feedstock for small-scale catalytic hydrogenation studies or electrochemical cell purging where trace oxygen must be excluded.
• Backup or primary H₂ source in facilities subject to compressed gas delivery delays or regulatory restrictions on cylinder storage.
• Teaching laboratories demonstrating principles of electrochemical gas generation, Faraday’s laws, and gas purity validation techniques (e.g., GC-TCD residual oxygen analysis).

FAQ

What type of water is required for operation?
Deionized water with resistivity ≥ 15 MΩ·cm and total organic carbon (TOC) < 50 ppb is mandatory. Tap or distilled water will cause rapid electrode fouling and membrane degradation.
How often does the KOH electrolyte need replacement?
Under normal operation (8 h/day, 5 days/week), the electrolyte requires replenishment every 6–12 months; the system alerts users via LED code when concentration drift exceeds calibration tolerance.
Can the SPH-300MT be used with GC–MS systems?
Yes—provided the instrument manufacturer confirms compatibility with externally generated H₂ and the lab implements appropriate moisture/oxygen traps upstream of the MS inlet.
Is remote monitoring supported out-of-the-box?
No native Ethernet or Wi-Fi interface is included; however, the RS-232 port supports connection to industrial PLCs or custom SCADA nodes for remote status polling and alarm triggering.
What maintenance is required beyond electrolyte management?
Annual inspection of pressure transducers, validation of flow sensor linearity against NIST-traceable calibrators, and replacement of the gas–liquid separator membrane every 24 months are recommended per Zhonghui Pu’s service protocol.