High-Temperature Catalytic Combustion TOC Analyzer

What is the High-Temperature Catalytic Combustion TOC Analyzer?

A high-temperature catalytic combustion TOC analyzer injects aqueous samples into a furnace at 680–720 °C with a platinum catalyst and measures CO2 by NDIR. It copes with salts, particulates, and refractory organics in wastewater, seawater, and environmental samples.

Overview

The high-temperature catalytic combustion TOC analyzer uses a combustion tube filled with a platinum-coated alumina catalyst held at 680–720 °C, or up to 900 °C for difficult matrices. A syringe injects 20–500 µL of sample, previously acidified and sparged when NPOC is measured. Organic carbon is oxidized to CO2 in a stream of purified air or oxygen at 150–200 mL/min. The gas passes through a dehumidifier and halogen scrubber before reaching the NDIR detector, and the integrated peak is converted to concentration. Because combustion is complete, recovery of particulates, humic substances, and high-molecular-weight organics is high. A 30–90 position autosampler with a stirring option keeps suspensions homogeneous. Typical detection limits are 4 µg/L with measurement range up to 30,000 mg/L with dilution or smaller injections. Salt deposits require periodic catalyst and tube maintenance.

How does it work?

A TOC analyzer separates carbon into inorganic carbon (carbonate and bicarbonate) and organic carbon. In the NPOC method, the sample is acidified to pH below 2 with hydrochloric or phosphoric acid and sparged with carrier gas so inorganic carbon leaves as CO2, then the remaining organic carbon is oxidized. High-temperature catalytic combustion injects the sample into a furnace at 680–1200 °C with a platinum or cobalt catalyst, converting organic carbon to CO2. Wet chemical oxidation uses persulfate and ultraviolet light to generate hydroxyl radicals at lower temperatures. The resulting CO2 is dried, halogens are scrubbed, and the gas passes through an NDIR cell at about 4.26 µm. Peak area is proportional to carbon mass and is calibrated with potassium hydrogen phthalate. Total nitrogen bound can be measured by chemiluminescence after combustion.

What are the key features?

• Platinum catalyst furnace at 680–720 °C fully oxidizes particulates and refractory organics.
• Injection volume of 20–500 µL matches ranges from µg/L to thousands of mg/L.
• NPOC and TC modes with automatic acidification and sparging.
• Autosampler with stirring keeps suspended solids homogeneous during injection.
• Halogen scrubber and dehumidifier protect the NDIR cell from corrosive gases.
• Automatic dilution extends range for high-carbon industrial wastewater.

What are the technical specifications?

A typical high-temperature catalytic combustion toc analyzer configuration offers measurement range (TC) of 4 µg/L–30,000 mg/L, detection limit of 4 µg/L (typical), combustion temperature of 680–720 °C (up to 900 °C), catalyst of Platinum on alumina, injection volume of 20–500 µL and repeatability (CV) of ≤1.5% at 10 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 High-Temperature Catalytic Combustion TOC Analyzer is used in wastewater and effluent testing, seawater and estuary monitoring, industrial process water analysis and landfill leachate characterization. Across the wider TOC Analyzers class, laboratories also deploy it for drinking water and surface water monitoring, wastewater and effluent compliance testing and soil and sediment organic carbon analysis.

Which standards and certifications apply?

Relevant standards and methods include ISO 8245, EN 1484, ASTM D7573, ASTM D4129, USP <643>, Ph. Eur. 2.2.44, ISO 10694 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.

Use carbon-free glassware or pre-baked vials and keep samples acidified and refrigerated if not analyzed immediately, because volatile organics are lost and microbial activity changes carbon. Ultra-pure carrier gas and low-blank water for calibration standards are essential at low ppb levels. Replace the combustion catalyst, halogen scrubber, and humidity trap based on sample load, and check the furnace tube for salt build-up with high-salt samples. Verify linearity with potassium hydrogen phthalate and check inorganic carbon recovery with sodium carbonate. System suitability in pharmaceutical use is performed with sucrose and 1,4-benzoquinone standards. Maintain calibration records and blank logs, and ensure ventilation for exhaust gas and acid fumes.

How do I select the right High-Temperature Catalytic Combustion TOC Analyzer?

Select this variant when samples contain particulates, salts, or high-molecular-weight organics, or when measurement range extends above 1000 mg/L. For ultrapure water below 100 µg/L, a UV-persulfate analyzer is usually more sensitive. In an RFQ, specify range, matrix, sample volume, autosampler size, and methods such as ISO 8245.

How does it compare with other TOC Analyzers variants?

The main selection criterion is the oxidation technique. High-temperature catalytic combustion handles particulate-laden, high-salt, and difficult organics, and covers ranges from 4 µg/L to 30,000 mg/L with suitable catalyst and injection volumes. UV-persulfate oxidation suits clean waters such as ultrapure and pharmaceutical water, with detection limits near 0.5 µg/L. Decide whether total nitrogen is needed and whether solid samples such as soils, sediments, or powders must be analyzed, because that requires a solid sample module with a furnace up to 900–1000 °C. Online process analyzers need continuous sampling, automatic calibration, and relay outputs. Consider autosampler capacity of 30–90 vials, sample volume, and the acid and catalyst consumption. Verify compliance with EN 1484, ISO 8245, and USP <643> when applicable.