UV-Fluorescence Total Sulfur and Chemiluminescence Nitrogen Analyzer

What is the UV-Fluorescence Total Sulfur and Chemiluminescence Nitrogen Analyzer?

This analyzer combusts liquid or gas samples at about 1050 °C and measures sulfur by UV fluorescence of excited SO2 and nitrogen by chemiluminescence of NO with ozone. It determines total sulfur and nitrogen from 0.3 to several thousand mg/kg in fuels, naphtha, LPG and petrochemical streams.

Overview

A microliter sample is injected into a quartz pyrolysis tube at 1000–1100 °C in an oxygen and argon atmosphere. Sulfur is oxidized to SO2, which is dried and excited by pulsed UV light near 214 nm, and the fluorescence emitted on relaxation is measured with a photomultiplier. For nitrogen, the combustion product NO reacts with ozone to produce excited NO2, whose chemiluminescence is also detected by photomultiplier. Linear ranges span about 0.3 to 10,000 mg/kg for sulfur and 0.3 to 1000 mg/kg for nitrogen. Sample introduction modules handle viscous and heavy liquids, volatile light hydrocarbons, LPG under pressure and solids by boat inlet. Automation enables unattended series with carryover controlled by solvent rinses.

How does it work?

Elemental analyzers convert the element of interest into a simple gas at high temperature and then measure that gas. In combustion analysis, a sample burns in oxygen at 900–1350 °C, converting carbon to CO2, hydrogen to H2O, sulfur to SO2 and nitrogen to N2 or NOx. Gases are separated by chromatographic column or selective traps and detected by non-dispersive infrared cells, thermal conductivity detectors or chemiluminescence. Inert gas fusion heats a sample in a graphite crucible under helium to release oxygen as CO, nitrogen as N2 and hydrogen as H2, again measured by infrared and thermal conductivity. Induction furnaces heat metals and ores with accelerators such as tungsten and tin. Calibration uses certified standards of known composition.

What are the key features?

• Quartz pyrolysis furnace at 1000–1100 °C with oxygen and argon flows
• Separate UV-fluorescence sulfur and chemiluminescence nitrogen detectors
• Syringe, boat and pressurized LPG inlets for different sample types
• Linear range covering sub-mg/kg to thousands of mg/kg without recalibration
• Membrane dryer and ozone scrubber for stable baseline
• Autosampler with solvent rinse to limit carry-over

What are the technical specifications?

A typical uv-fluorescence total sulfur and chemiluminescence nitrogen analyzer configuration offers sulfur range of 0.3–10,000 mg/kg, nitrogen range of 0.3–1,000 mg/kg, sulfur detection limit of ≈ 0.3 mg/kg, pyrolysis temperature of 1000–1100 °C, injection volume of 5–80 µL (liquid) and sulfur repeatability of RSD ≤ 2% at 10 mg/kg. 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 UV-Fluorescence Total Sulfur and Chemiluminescence Nitrogen Analyzer is used in ultra-low sulfur diesel and gasoline compliance, nitrogen in naphtha and catalyst poisoning studies, sulfur in LPG and light hydrocarbons, total sulfur in lubricants and crude oil and sulfur in ethanol and biodiesel blends. Across the wider Elemental Analyzers class, laboratories also deploy it for carbon and sulfur in steel and ores, oxygen, nitrogen and hydrogen in metals and alloys and ultimate analysis of coal and coke.

Which standards and certifications apply?

Relevant standards and methods include ASTM E1019, ASTM E1409, ASTM D5373, ASTM D5453, ASTM D4239, ISO 15350, ISO 10694 and IEC 61010-1. Certification candidates for this model are CE, ISO 9001 manufacturing and RoHS; each is to be confirmed for the specific configuration before shipment, and certificates are supplied only where they have been issued.

Elemental analyzers need clean, dry, high-purity gases, typically oxygen and helium or argon at 99.995% or better, with regulators and moisture traps. Condition new combustion tubes, catalysts and reagents according to the manual, and replace them on a usage schedule. Run blanks and conditioning samples at start-up, then calibrate with certified standards that match the expected concentration range, such as acetanilide for CHN or steel standards for C and S. Control dust by cleaning the furnace and filters frequently, especially for ore and coke samples. Check for gas leaks regularly, weigh samples on a balance with suitable readability, and keep crucibles pre-ignited and free of contamination.

How do I select the right UV-Fluorescence Total Sulfur and Chemiluminescence Nitrogen Analyzer?

Select this variant for regulatory sulfur and nitrogen control in fuels at mg/kg levels, where XRF sensitivity is insufficient. For percent-level sulfur in solids use the induction furnace sibling. In an RFQ, specify sulfur and nitrogen ranges, sample types including LPG or viscous oils, autosampler need, gas supplies and methods such as ASTM D5453 and ISO 20846.

How does it compare with other Elemental Analyzers variants?

Select by element set and sample form. Carbon and sulfur in steel, ores, cement and ceramics point to a high-frequency induction furnace with infrared detection. Oxygen, nitrogen and hydrogen in metals call for an inert gas fusion analyzer. Organic samples requiring C, H, N, S and possibly O suit a CHNS/O dynamic-flash combustion analyzer. Sulfur or nitrogen at mg/kg levels in liquid fuels suit UV-fluorescence or chemiluminescence analyzers. Check measuring range, since percent-level and ppm-level analyses need different detector ranges. Consider sample throughput, autosampler capacity, consumables such as crucibles, anhydrone and catalysts, and the standard methods to be met, such as ASTM E1019 or ASTM D5453.