Coulometric vs Infrared Sulfur Analyzers: Which Fits Your Lab?
Method basics
Coulometric analyzers (GB/T 214, ISO 16994) titrate the SO₂ electrolytically — absolute quantification with no calibration gas, at modest equipment cost. Infrared analyzers (GB/T 25214) burn the sample at 1350 °C and read SO₂ by IR absorption: ~120 s per sample, no electrolyte, ideal for high throughput.
Decision matrix
Choose coulometric if: budget is tight, daily sample count < 50, or you need the classical arbitration method. Choose infrared if: you run hundreds of samples daily, want walk-away automation with 24+ position feeders, or electrolyte handling is a burden.
High-throughput labs increasingly pair both: IR for routine screening, coulometric for confirmation and disputes.
Robotics change the math
Robotic coulometric models now load 25+ samples with unlimited top-up and automatic WO₃ dosing, closing most of the throughput gap while keeping the arbitration method — a strong option for mine-mouth labs with variable truck arrivals.
Frequently Asked Questions
What is the main decision covered in “Coulometric vs Infrared Sulfur Analyzers: Which Fits Your Lab?”?
Both measure total sulfur to 0.001 % resolution — but reagent cost, throughput and sample matrix decide which belongs on your bench.
Can RoyIntelli recommend an instrument for a specific laboratory?
Yes. Send the sample type, daily throughput, required testing standard, destination country and voltage. An engineer can then confirm a suitable configuration and quotation.
Need a specific recommendation?
Tell us your sample type and daily throughput — an engineer will review the method fit and confirm the configuration in writing.
Ask an EngineerRelated industry applications
This guide is written for laboratories in these sectors. Each page lists a typical configuration, the standards normally named in its tenders and the documents available for a bid.
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