HUANKONG CH-2000 Sulfide Acidification and Purge Apparatus

Overview

The HUANKONG CH-2000 Sulfide Acidification and Purge Apparatus is a dedicated laboratory instrument engineered for the quantitative determination of dissolved and acid-volatile sulfide (AVS) species in aqueous environmental matrices. It operates on the principle of acidification–purge–trapping: sulfur-containing species (e.g., HS⁻, S²⁻, metal sulfides) in water samples are converted to hydrogen sulfide (H₂S) under controlled acidic conditions (typically with hydrochloric acid), followed by inert gas (nitrogen) purging to quantitatively transfer liberated H₂S into a pre-filled absorbent solution—commonly zinc acetate–sodium acetate buffer or 2% sodium hydroxide. This methodology aligns with standardized wet-chemical analytical workflows required for compliance with environmental monitoring protocols. Designed for routine application in municipal, industrial, and regulatory laboratories, the CH-2000 ensures high reproducibility, minimal cross-contamination risk, and strict adherence to method-defined reaction kinetics and mass-transfer conditions.

Key Features

• Six independent reaction modules housed in a single integrated chassis, enabling parallel processing of up to six samples without interference between units.
• Triple-port reaction vessel design: separate, sealed inlet ports for HCl addition, nitrogen gas supply, and gas exhaust—each isolated to prevent backflow, pressure imbalance, or reagent carryover.
• PID-controlled constant-temperature water bath system (range: ambient to 80 °C, ±0.3 °C stability) with rapid thermal equilibration (<15 min from startup to setpoint), minimizing method variability due to temperature drift.
• Removable 316 stainless steel sample carrier tray—chemically inert to concentrated HCl, NaOH, and oxidative agents; rated for continuous use at temperatures up to 95 °C.
• Individual digital mass flow controllers (MFCs) for each channel, permitting precise, adjustable nitrogen flow rates (0–1.5 L/min, resolution: 0.01 L/min) with real-time monitoring and logging capability.
• Dual redundant safety mechanisms: mechanical overpressure relief valve + electronic pressure cutoff sensor, automatically terminating gas flow if system pressure exceeds 120 kPa.
• Automated water management system: level-sensing reservoir with auto-fill function and audible/visual low-water alarm, preventing dry-heating damage during unattended operation.

Sample Compatibility & Compliance

The CH-2000 supports analysis of diverse aqueous matrices including surface water, groundwater, domestic wastewater, and industrial effluents containing suspended solids (up to 500 mg/L TSS). Its modular architecture accommodates standard 100–500 mL borosilicate glass reaction vials and absorption tubes compliant with ASTM D4129–17 and ISO 11057:2017 guidelines for volatile sulfide recovery. The instrument meets functional requirements specified in GB/T 16489–1996 (equivalent to APHA 4500-S²⁻ B), HJ/T 60–2000, and the Chinese Ministry of Ecology and Environment’s “Methods for Examination of Water and Wastewater (4th Edition)”. All wetted components conform to USP Class VI biocompatibility standards, and the system architecture supports audit-ready documentation per GLP and ISO/IEC 17025:2017 laboratory quality management systems.

Software & Data Management

While the CH-2000 operates as a standalone hardware platform, it integrates seamlessly with external data acquisition systems via RS-232 and optional USB-to-serial interface. Each module logs timestamped operational parameters—including actual bath temperature, nitrogen flow rate, acid addition time, and purge duration—to CSV files compatible with LIMS platforms. Optional firmware upgrade enables 21 CFR Part 11-compliant electronic signatures, user access control tiers (admin/operator/auditor), and immutable audit trails for critical process events (e.g., temperature deviation alerts, flow interruption, water refill cycles). All calibration records, maintenance logs, and method validation reports can be exported in PDF format with embedded digital signatures.

Applications

• Regulatory compliance testing for sulfide discharge limits under national and provincial environmental protection statutes.
• Process monitoring in pulp & paper mills, tanneries, petroleum refineries, and chemical manufacturing facilities where sulfide generation is a known byproduct.
• Research-grade speciation studies involving redox-sensitive sulfur compounds in sediment porewater and anaerobic digesters.
• Method validation and interlaboratory comparison exercises coordinated by national metrology institutes and environmental accreditation bodies.
• Training and proficiency testing in university environmental chemistry laboratories and third-party certification centers.

FAQ

What types of absorbent solutions are compatible with the CH-2000?

Zinc acetate–sodium acetate buffer (pH ≈ 4.5) and 2% sodium hydroxide solution are the two primary absorbents validated per GB/T 16489–1996 and HJ/T 60–2000. Other alkaline or chelating absorbents may be used subject to method verification.
Can the CH-2000 be used for total sulfide analysis in solid-phase samples?

Yes—when coupled with an ultrasonic-assisted extraction step prior to acidification, the instrument supports AVS quantification in sediments and sludge according to EPA Method 1630 and ISO 16264:2003.
Is remote monitoring supported?

Local Ethernet connectivity is not built-in, but the RS-232 interface allows integration with SCADA or LabVIEW-based supervisory systems for centralized status monitoring and alarm notification.
What maintenance intervals are recommended?

Quarterly inspection of O-rings, MFC calibration verification, and annual replacement of water bath heating elements and PID controller firmware updates are advised per the manufacturer’s maintenance schedule.
Does the instrument meet CE or UL safety certification?

The CH-2000 complies with IEC 61010-1:2010 for electrical safety in laboratory equipment. CE marking is available upon request for EU-market configurations; UL listing requires regional adaptation and third-party testing.