Application of Sample Combustion to Determine Chloride and Sulfate Content

This experiment was performed to determine chloride and sulfate in a highly viscous oil sample applying sample combustion before anion chromatography with conductivity detection after sequential suppression.

The sample is viscous oil, 40mg sample, Mitsubishi AQF-100 was combusted at 1000°C. The combustion gases were collected in ultrapure water containing 300 ppm H2O2 and subsequently injected.

Figure 1. Determination of chloride and sulfate (not quantified) in a highly viscous petrochemical sample applying sample combustion followed by anion chromatography with conductivity detection after sequential suppression. The sample has a particularly high sulfate content.


Mean (injected) [mg/L] Mean (in sample) [mg/kg]
Chloride 0.28 36.5
Nitrite n.q. -
Nitrate n.q. -
Phosphate (internal standard) 1.00 -
Sulfate n.q. -


The experiment details are as follows:

  • Sample - Viscous oil
  • Sample Preparation – Combustion
  • Eluent: 3.2mmol/L sodium carbonate 1.0mmol/L sodium hydrogen carbonate
  • Suppressor: Sequential suppression (MSM: 50 mmol/L H2SO4)
  • Flow: 0.7mL/min
  • Injection Volume: 100µL.


Metrosep A Supp 5 - 150/4.0 6.1006.520
Metrosep A Supp 4/5 Guard/4.0 6.1006.500


Eluent 3.2mmol/L sodium carbonate
1.0mmol/L sodium hydrogen carbonate
Suppressor regenerant 100mmol/L sulfuric acid
Rinsing solution Ultrapure water
Absorbtion solution 300mg/L hydrogen peroxide
1.0mg/L phosphate


Conductivity after sequential suppression.


Flow rate 0.7 mL/min
Injection volume 100µL
Pmax 15MPa
Recording time 18min
Column temperature 30°C

Combustion Parameters

Oven temperature
Inlet/outlet 900/1000°C
Absorption solution 5.0mL


881 Compact IC pro – Anion – MCS 2.881.0030
IC Conductivity Detector 2.850.9010
Remote box 6.2148.010
Mitsubishi AQF-100 *
Mitsubishi ABC-100 *
Mitsubishi WS-100 *
Mitsubishi GA-100 *

* from local Mitsubishi distributor/not shown in system graphic below.

About Metrohm

Metrohm is a leading manufacturer of high-precision instruments for chemical analysis. We offer a complete line of analytical laboratory and process systems for titration, ion chromatography, spectroscopy, and electrochemistry.

Manufactured in Switzerland since 1943, our instruments have a unique reputation for their robust design and outstanding quality. With thousands of installations worldwide, we are the established leader in titration.

From the beginning, our sales engineers guide you through the instrument purchasing process. Together with our team of application chemists we create unique solutions for your laboratory needs. From installation to routine preventative maintenance, our global team of certified service professionals ensures ongoing performance and reliability of your Metrohm instrument.

Whether it is replacing an existing instrument, developing a new analytical solution or answering your technical questions – we are here for you. Our local presence, with offices or subsidiaries in over 120 countries, makes Metrohm your neighbor. Metrohm is a familiar face and shares your professional background.

Lab Solutions

Metrohm is at the forefront of laboratory automation and analysis, increasing the productivity of your lab.

Process Solutions

Metrohm understands how to translate laboratory analysis methods into accurate and reliable online analysis.

This information has been sourced, reviewed and adapted from materials provided by Metrohm.

For more information on this source, please visit Metrohm.

Tell Us What You Think

Do you have a review, update or anything you would like to add to this article?

Leave your feedback