TOC-TN Analyzer for Water Samples with Autosampler

What is the TOC-TN Analyzer for Water Samples with Autosampler?

A laboratory analyzer that measures total organic carbon and total nitrogen bound in a single combustion run, using NDIR for CO2 and chemiluminescence for nitrogen oxide. It suits wastewater and surface water labs reporting both carbon and nitrogen loads.

Overview

This variant adds a chemiluminescence detector for nitric oxide to the usual combustion and NDIR platform. Total bound nitrogen, including ammonium, nitrate, nitrite and organic nitrogen, is converted to NO at 720 °C, then reacted with ozone to produce light proportional to concentration. The same injection yields TOC or NPOC and TNb, cutting analysis time and sample volume compared with running separate Kjeldahl or persulfate digestion methods. Typical ranges are 0.5 to 25,000 mg/L for carbon and 0.5 to 10,000 mg/L for nitrogen, with a detection limit near 0.05 mg/L for TNb. A 50-position autosampler, automatic dilution and sparging enable unattended overnight batches. The platform suits effluent reporting where nutrient limits apply, as well as limnology and aquaculture studies. An ozone generator and an ozone destructor are additional components, and they require dry gas and periodic service.

How does it work?

A TOC analyzer converts all organic carbon in a water sample to CO2 and quantifies the gas. Two oxidation routes dominate. High-temperature catalytic combustion injects the sample into a furnace at 680–900 °C containing a platinum or similar catalyst, which also handles particulates and difficult compounds. UV-persulfate oxidation adds sodium persulfate and irradiates the sample with UV at 185 and 254 nm to generate hydroxyl radicals. Inorganic carbon is removed first by acidification and sparging, or measured separately to give TOC by difference. The CO2 is carried by purified air or oxygen to a non-dispersive infrared detector, or measured by membrane conductometry in low-level systems. Peak area is integrated and converted to concentration using a multi-point calibration against potassium hydrogen phthalate standards.

What are the key features?

• Single injection reports TOC or NPOC and total bound nitrogen together
• Chemiluminescence NO detector with ozone generator and destructor
• 50-position autosampler with automatic dilution and sparge
• Wide carbon range up to 25,000 mg/L and nitrogen up to 10,000 mg/L
• Cuts analysis time and sample volume versus separate digestion methods
• Stored method templates for ISO, ASTM and HJ procedures

What are the technical specifications?

A typical toc-tn analyzer for water samples with autosampler configuration offers oxidation method of Catalytic combustion, 720–850 °C, TOC range of 0.5–25,000 mg/L, TNb range of 0.5–10,000 mg/L, carbon detector of NDIR, nitrogen detector of Chemiluminescence (NO + O3) and detection limit (TNb) of ≤ 0.05 mg/L. Values are indicative of the product class; the exact figures for each configuration are confirmed on the quotation and the calibration documents supplied with the instrument.

Which applications is it used for?

The TOC-TN Analyzer for Water Samples with Autosampler is used in wastewater nutrient discharge reporting, eutrophication studies in lakes and reservoirs, aquaculture water quality assessment and leachate and digestate characterization. Across the wider TOC Analyzers class, laboratories also deploy it for drinking water treatment monitoring, wastewater discharge compliance and surface water and groundwater surveys.

Which standards and certifications apply?

Relevant standards and methods include ISO 8245, ASTM D4839, ASTM D5173, ASTM D5904, USP <643>, Ph. Eur. 2.2.44, HJ 501 and IEC 61010-1. Certification candidates for this model are CE and ISO 9001 manufacturing; each is to be confirmed for the specific configuration before shipment, and certificates are supplied only where they have been issued.

Install the analyzer on a stable bench with clean, dry carrier gas at 99.99% purity or a zero-air generator, and provide ventilation for exhaust. Calibrate at least monthly with potassium hydrogen phthalate and verify with sodium carbonate and a blank each run. Keep glassware organic-free and use ultrapure water blanks, since ambient organics cause high blanks. Replace combustion catalyst, halogen scrubbers and persulfate reagent on the schedule stated by the manufacturer. For regulated laboratories, confirm software audit trails and user access levels, and run system suitability with sucrose and benzoquinone to check oxidation efficiency where USP <643> applies.

How do I select the right TOC-TN Analyzer for Water Samples with Autosampler?

Choose the TOC-TN variant when carbon and nitrogen are both reported for the same samples, as they are in many wastewater permits and eutrophication studies. A carbon-only analyzer is simpler and cheaper if nitrogen is measured elsewhere. In an RFQ, give TOC and TN ranges, sample matrix, number of samples per day and applicable methods such as ISO 20236 or HJ 636.

How does it compare with other TOC Analyzers variants?

The decisive parameters are sample matrix, measuring range and operating mode. Wastewater and effluents with particulates, high salt or high carbon load call for high-temperature combustion with a robust injection system and dilution capability. Drinking water and cleaner surface water, typically below 20 mg/L, are well served by UV-persulfate or low-temperature oxidation with sub-0.1 mg/L resolution. Semiconductor and pharmaceutical purified water need online ppb-level sensors with conductivity-based detection. Decide whether you need laboratory batch analysis with an autosampler or continuous online data. If nitrogen loading matters for discharge permits, a combined TOC-TN configuration saves a second instrument. Also check the method you must follow, such as ISO 8245 or USP <643>, and the consumables cost of gases, catalyst and reagents.