Sulfimax GX – Total H₂S Analysis Across Petroleum, Water, and Wastewater Industries

Accurate measurement of hydrogen sulfide (H₂S) is essential for both safety and process reliability. H₂S is highly toxic — exceeding the odour threshold at just 3–5 ppm and posing severe health risks beyond 10 ppm. At concentrations above 1000 ppm, fatality can occur within minutes. Beyond its health hazards, H₂S is also highly corrosive, capable of damaging refinery equipment and infrastructure at rates of up to 10 mm per year.

To meet these challenges, ECH Elektrochemie Halle developed the Sulfimax GX, a versatile analyser designed for full compliance with key international test methods:

• ASTM D8536-25: Determination of available sulfide in water and wastewater by gas extraction.
• IP 570, (Procedure B): Determination of H₂S in liquid petroleum products.
• ASTM D7621 (Procedure B): Determination of H₂S in crude oil, fuel oils, and other petroleum fractions.

Multi-Matrix Application

The Sulfimax GX enables reliable H₂S quantification across a wide range of samples:

• Water & Wastewater → compliant with ASTM D8536-25, using acidification and gas extraction to generate and measure H₂S down to 0.01 ppm.
• Liquid Petroleum Products (crude oil, gasoline, diesel, marine fuels) → analysed according to IP 570 (Procedure B) and ASTM D7621 (Procedure B), ensuring results that meet industry standards.
• Solid Products (bitumen, tar, elemental sulfur) and Gas Products (LPG, NG, LNG, mixed gases) → measured with the headspace and LPG sampling modules.

Methodology & Detection

Using an electrochemical detector with an advanced gas extraction system, the Sulfimax GX measures H₂S across a broad dynamic range (0.01–10,000 ppm) with typical measurement times of ~5 minutes. Potential interferences, such as mercaptans, are eliminated through a dedicated white oil extraction step. After analysis, H₂S is safely neutralised in an activated carbon filter, eliminating the need for a fume hood.

For petroleum and solid products, the newly revised Vario headspace module allows controlled heating (up to 180 °C) to liberate H₂S from the sample. The Vario module also includes a new autosampler, enabling fully automated analysis for both IP 570 (Procedure B) and ASTM D7621 (Procedure B) procedures. For aqueous matrices, the system follows ASTM D8536-25, where samples undergo phosphoric acid acidification to release H₂S before detection.

Configurations

The Sulfimax GX is available in multiple formats to meet laboratory, portable, and online monitoring needs:

• Sulfimax GX Lab – Bench-top system with Vario headspace, autosampler, and LPG options.
• Sulfimax GX Go – Portable system with handle and optional portable headspace/LPG kits.
• Sulfimax GX Online (ATEX) – Continuous analyser for petroleum applications in hazardous zones.
• Sulfimax GX Online (Water) – Continuous H₂S monitoring in wastewater and aqueous samples.
• Sulfimax GX Online (Gas) – Continuous analyser for natural gas and other gaseous mixtures.

See the Sulfimax GX in action at ArabLab, booth H3-D54.

For more details on our full range of H₂S analysers, contact or visit Sulfimax GX Vario.