Hach QP1680 Total Organic Carbon (TOC) and Total Nitrogen (TN) Analyzer
| Brand | Hach |
|---|---|
| Origin | Imported |
| Manufacturer Type | Manufacturer |
| Model(s) | QP1680-TOC, QP1680-TOC/TN, QP1680-TN |
| Instrument Type | Laboratory TOC/TN Analyzer |
| Detection Principle | Non-Dispersive Infrared (NDIR) Absorption |
| Oxidation Method | High-Temperature Catalytic Combustion |
| Measurement Range | TC, TIC, NPOC, TN: 0–30,000 mg/L |
| Detection Limits | TC/TIC/NPOC > 50 µg/L |
| Resolution | Particles ≤ 800 µm |
| Repeatability | < 5% (0–10 mg/L) |
Overview
The Hach QP1680 Total Organic Carbon (TOC) and Total Nitrogen (TN) Analyzer is a laboratory-grade, dual-parameter elemental carbon and nitrogen analyzer engineered for precision, robustness, and operational efficiency in regulated and research-driven water quality laboratories. It employs high-temperature catalytic combustion oxidation (680–900 °C) to quantitatively convert organic carbon and total nitrogen compounds in aqueous samples into CO₂ and NOₓ, respectively. These gaseous products are then measured using non-dispersive infrared (NDIR) detection — a method recognized for its specificity, linearity, and long-term stability across wide concentration ranges. The instrument supports multiple analytical modes: Total Carbon (TC), Inorganic Carbon (TIC), Non-Purgeable Organic Carbon (NPOC), TOC (calculated as TC − TIC), and TN (via chemiluminescence or NDIR-based NOₓ detection depending on configuration). Designed for compliance with international water quality standards including ISO 8245, ASTM D5905, USP , and EPA Method 415.3, the QP1680 delivers trace-level sensitivity and high reproducibility without compromising system uptime or method flexibility.
Key Features
- Integrated 65-position liquid autosampler with programmable sample agitation — eliminates manual handling and ensures homogeneous particulate suspension prior to injection.
- Direct-injection sample introduction architecture — bypasses internal syringe pumps to minimize carryover and cross-contamination, particularly critical for high-solids or viscous matrices.
- Valve-free fluidic pathway — accommodates suspended particles up to 800 µm in diameter, enabling direct analysis of raw wastewater, groundwater with sediment, or pretreated industrial effluents without filtration.
- High-stability ceramic combustion tube with proprietary catalyst formulation — optimized for extended service life (>12 months under routine operation) and resistance to halogen- or sulfur-containing interferences.
- Modular hardware design — TN measurement capability is field-upgradable via plug-in TN module, allowing users to scale functionality without replacing core instrumentation.
- Hot-swap consumables architecture — quartz combustion tubes, NDIR cells, and catalyst cartridges feature tool-free installation and calibration-traceable part numbering for GLP-compliant maintenance logging.
Sample Compatibility & Compliance
The QP1680 accepts a broad spectrum of aqueous matrices without mandatory pretreatment: municipal and industrial wastewater, surface and groundwater, drinking water, cooling tower water, pharmaceutical process water, and reclaimed water. Its particle-tolerant inlet enables analysis of unfiltered samples containing colloidal organics or fine suspended solids — reducing preprocessing time and preserving representative carbon/nitrogen speciation. The system complies with data integrity requirements per FDA 21 CFR Part 11 when operated with Hach’s validated software suite, supporting electronic signatures, audit trails, and user-access controls. Routine performance verification aligns with ISO/IEC 17025 quality management systems and supports accreditation for environmental testing laboratories (e.g., NELAC, UKAS, DAkkS).
Software & Data Management
Hach QP1680 Control Software provides a validated, Windows-based interface for method setup, sequence programming, real-time diagnostics, and report generation. All analytical parameters — oxidation temperature, acidification volume, purge duration, integration windows — are fully configurable and stored with metadata (operator ID, timestamp, calibration history). Raw NDIR absorbance traces, peak area integrations, and QC flagging (e.g., baseline drift, catalyst saturation, detector saturation) are retained in an encrypted SQLite database. Export formats include CSV, PDF analytical reports, and LIMS-ready XML files compliant with ASTM E1468 and HL7 standards. Software validation documentation (IQ/OQ/PQ protocols) and change control records are available upon request for GxP-regulated environments.
Applications
- Regulatory compliance monitoring for TOC/TN in wastewater discharge permits (e.g., NPDES, EU Urban Wastewater Treatment Directive).
- Source water characterization and treatment optimization in drinking water utilities.
- Pharmaceutical water system validation (PW, WFI) per USP and EP 2.2.44.
- Industrial process water tracking in petrochemical, semiconductor, and food & beverage manufacturing.
- Research applications in biogeochemical cycling, nutrient loading studies, and advanced oxidation process (AOP) efficiency evaluation.
- Third-party certification and contract testing in accredited environmental laboratories.
FAQ
What sample preparation is required before analysis?
Minimal preparation is needed. Samples with suspended solids ≤800 µm may be injected directly. For highly turbid or viscous samples, optional centrifugation or gentle filtration (≥10 µm pore size) is recommended to avoid nozzle clogging — though not required for method validity.
Can the QP1680 measure both TOC and TN in a single run?
Yes — the QP1680-TOC/TN configuration performs sequential TOC and TN determination within one automated sequence, using shared combustion and detection modules with reagent-switching logic to prevent cross-interference.
How is system performance verified daily?
Built-in daily verification includes multi-point calibration checks using certified KHP (for TOC) and potassium nitrate (for TN), plus system blank assessment and catalyst activity monitoring via reference standard recovery.
Is the instrument compatible with LIMS integration?
Yes — the software supports bidirectional communication via ASTM E1394 and HL7 v2.x protocols, enabling automated result transfer, sample ID synchronization, and status polling.
What maintenance intervals are recommended for routine operation?
Catalyst replacement every 12–18 months (depending on sample load and matrix), quartz combustion tube inspection every 6 months, and NDIR cell cleaning quarterly — all tracked automatically in the maintenance log module.
