Binzhenghong 50 mL Custom COD Microwave Digestion Vessels for Total Nitrogen (TN) and Chemical Oxygen Demand (COD) Water Analysis
| Brand | Binzhenghong |
|---|---|
| Origin | Jiangsu, China |
| Manufacturer Type | Direct Producer |
| Origin Classification | Domestic (China) |
| Capacity | 50 mL |
| Pricing | Available Upon Request |
Overview
The Binzhenghong 50 mL Custom Microwave Digestion Vessels are engineered specifically for rapid, high-efficiency sample preparation in regulatory-compliant chemical oxygen demand (COD) and total nitrogen (TN) analysis of aqueous environmental samples. These vessels operate within sealed microwave digestion systems—utilizing controlled microwave energy to accelerate oxidative decomposition under elevated temperature and pressure. The digestion process employs acidic oxidants (e.g., K₂Cr₂O₇/H₂SO₄ for COD; persulfate or alkaline persulfate for TN) to convert organic carbon and nitrogenous compounds into measurable end-products (CO₂ and NO₃⁻, respectively). Designed for compatibility with standard 700 W microwave digestion platforms, each 50 mL vessel supports complete mineralization of wastewater, surface water, and domestic sewage matrices while maintaining trace-level integrity and minimizing reagent consumption. This aligns with the principle of green analytical chemistry—reducing acid volume by >70% and shortening digestion time to 5–20 minutes versus the conventional 2-hour reflux method (ISO 6060, APHA 5220C, HJ 828-2017).
Key Features
- Chemically inert construction from high-purity polytetrafluoroethylene (PTFE), certified for resistance to concentrated H₂SO₄, HNO₃, and K₂Cr₂O₇ at temperatures up to 220 °C and pressures exceeding 3 MPa.
- Precision-machined 50 mL nominal capacity with ±0.5 mL volumetric tolerance, optimized for gravimetric and volumetric accuracy during post-digestion dilution and spectrophotometric quantification.
- Integrated sealing cap with pressure-relief micro-valve to prevent over-pressurization while retaining volatile analytes (e.g., NH₃, NOₓ derivatives) during TN digestion.
- Autoclavable and reusable design—validated for ≥50 consecutive digestion cycles without measurable leaching of fluoropolymers or metal contaminants (ICP-MS screening per EPA Method 6020B).
- Dimensionally standardized to fit common 6-position and 12-position rotor configurations used in benchtop microwave digestion systems (e.g., CEM MARS, Anton Paar Multiwave PRO, and domestic equivalents).
Sample Compatibility & Compliance
These vessels are validated for use with diverse aqueous matrices including municipal wastewater, industrial effluents, river and lake water, and digested sludge filtrates. They meet performance criteria outlined in Chinese national standards HJ 828-2017 (for CODCr), HJ 636-2012 (for TN), and GB 11893–11915-89 (water quality vocabulary and analytical methods). When deployed in accordance with GLP-compliant laboratory protocols, the system demonstrates ≤5.0% intra-laboratory RSD for CODCr values between 80–150 mg/L and correlation coefficients r > 0.999 against reference closed-reflux titrimetric (ISO 6060) and alkaline persulfate UV spectrophotometric (ISO 11908) methods. Chloride interference is mitigated up to 10,000 mg/L Cl⁻ via Ag₂SO₄ precipitation pre-treatment—ensuring robustness in saline-influenced samples.
Software & Data Management
While the vessels themselves are passive consumables, their use integrates seamlessly into LIMS-enabled workflows when paired with microwave systems supporting digital protocol storage, audit trails, and electronic signature compliance. For laboratories operating under FDA 21 CFR Part 11 or ISO/IEC 17025 requirements, full traceability is achieved through synchronized timestamped digestion logs—including power ramp profiles, hold temperatures, and real-time pressure monitoring. Raw absorbance data from subsequent UV-Vis (e.g., Hach DR6000) or ICP-OES measurements can be directly imported into validated software packages (e.g., Thermo Fisher QExactive, Agilent MassHunter) for automated calibration curve fitting and uncertainty propagation per GUM (JCGM 100:2008).
Applications
- Routine monitoring of COD and TN in wastewater treatment plant influent/effluent streams for discharge compliance reporting (e.g., China’s “Water Pollution Prevention and Control Action Plan”).
- Research-scale evaluation of biodegradability indices (BOD5/COD ratio) and nitrogen transformation pathways in activated sludge systems.
- Method validation studies comparing microwave-assisted digestion against EPA Methods 410.4 (COD) and 353.2 (TN) under interlaboratory collaborative testing frameworks.
- Quality control of drinking water source protection zones where low-level TN detection (<0.05 mg/L) requires minimal blank contribution and high recovery consistency.
FAQ
Are these vessels compatible with non-Binzhenghong microwave digestion systems?
Yes—mechanical dimensions and thread specifications conform to ISO/IEC 17025-recognized universal rotor interfaces; compatibility verification is recommended prior to first use.
What is the maximum recommended operating temperature and pressure?
The PTFE vessels are rated for continuous operation up to 220 °C and 3 MPa; exceeding these limits may compromise seal integrity and introduce systematic bias.
How should the vessels be cleaned between uses?
Rinse thoroughly with deionized water after each digestion, followed by soaking in 10% v/v HNO₃ for 30 minutes, then triple-rinsing with ultrapure water (≥18.2 MΩ·cm); air-dry in Class 100 laminar flow hood.
Do they comply with ISO 17025 documentation requirements?
Each batch undergoes certificate-of-conformance issuance—including lot-specific material certification, dimensional inspection reports, and extractable metals testing per USP .
Can they be used for total phosphorus (TP) digestion?
Yes—validated for TP analysis per HJ 670-2013 using ammonium molybdate spectrophotometry; recovery rates exceed 98.5% across 0.01–0.6 mg/L range.
