Your TOC analysis has never been easier with LECO’s solutions

Carbon is an essential building block of life on our planet. The amount of Carbon present is an important factor in soils and agriculture samples.

The determination of TOC in solids has recently become ever more important, not just for evaluating wastes but TOC content measurements are also an important aspect of assessing soils.

The Carbon present in soil organic matter is referred to as organic Carbon. Soil organic Carbon is a vital component of productive agriculture. In addition sequestration of Carbon in agricultural soils has been recognised as a tool to mitigate climate change.

LECO provides innovative and timesaving analytical instrumentation for the analysis of organic Carbon content.

Specific Advantages Including

  • Market leading analytical performance
  • Simplified sample preparation
  • Robust & reliable instrumentation
  • Unsurpassed instrument flexibility
  • Adhering to all the current standards, such as ISO 10694, BS EN 17505 and EN 15936


Instrument Portfolio for TOC Analysis

LECO CS744 Series

CS744 // Carbon analysis by combustion

Redefine the way you determine carbon in soils and plant tissues with our 744 series. Using extensive customer feedback and innovative engineering, the 744 takes advantage of our immersive CORNERSTONE® brand software platform and a number of features, ...

... such as an improved IR cell design and available automation, come together to increase usability, lab productivity, and lower your cost-per-analysis.

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RC612 // Multi-Phase Carbon And Water Determination

Get fast, reliable carbon and water determination with our RC612. The RC612 is a resistance furnace multiphase carbon and moisture determinator which quantifies the carbon and moisture present in soils and plant tissues and illustrates the source of several types of carbon.

The RC612 features a state-of-the-art furnace control system, which allows the temperature of the furnace to be stepped and ramped from near ambient to 1,100 °C, in either oxidative or reductive carrier gas. The RC612 utilizes an afterburner furnace that ensures complete combustion of volatile species released at lower primary furnace temperatures.

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LECO SC832 Series

SC832 // Sulfur And Carbon Analysis

LECO’s 832 series of Elemental Determinators are specifically designed to perform carbon and sulfur analysis of soil, plant tissue and other organic and some inorganic materials. The 832 series is a valuable resource for any laboratory needing fast and accurate analysis.


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Methods of TOC analysis include

1. Acid Digestion Method

The most common method for determining TOC is the acid digestion method. By acid treating a sample, usually with hydrochloric acid, which is strong enough to react with inorganic carbonates but does not react much with organic Carbon, the inorganic carbonate species within the sample will effervesce as Carbon dioxide. The acid-treated sample and a non-acid-treated sample can both be analyzed using either the LECO C744 series or LECO C832 series for Carbon content. The untreated sample would indicate the total carbon content, while the acid-treated sample’s Carbon content would be the remaining organic Carbon content. The difference between the two samples would be the total inorganic Carbon (TIC) content.


2. Temperature Dependent Method

Another Carbon determination method is temperature dependent. With the temperature dependent method, samples do not need to be pretreated. Organic Carbon combusts to CO2 between 150 °C and 450 °C, while inorganic species combust below 1,000 °C. The RC612 resistance furnace multiphase Carbon and moisture determinator performs this analysis by using a two-step temperature ramping at 450 °C and 1,000 °C without any acid pretreatment of the samples. The CO2 gases are swept through to an NDIR at 450 °C and again at 1,000 °C to determine the TOC and TIC in the sample.

For a more comprehensive exploration of these two methods, as well as an in-depth comparison of LECO instrumentation, please contact us:



On-demand Presentation // Watch the recorded Webinar

On-Demand Video Webinar TOC Analysis, preview on screen

Total Organic Carbon (TOC) Determination in Soil Using Acid Treatment and Temperature Differentiation

Presented by Jeffery Gast

The presentation will outline TOC determination in soil using two different approaches. First, we will explore the use of acid treatment of the soil to remove carbonates followed by analysis using conventional combustion techniques. Next, we will explore using a ramped furnace temperature approach to differentiate organic and inorganic carbon species. TOC results from both approaches will be presented.



Publication Library

Dive deeper into TOC analysis

Enhance your knowledge with our selection of publications. Discover techniques, comparisons, and applications in our downloadable resources, gaining valuable insights and enriching your understanding of Total Organic Carbon (TOC) analysis.

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Learn more about TOC analysis with LECO

If you want to learn more about our products and solutions for TOC analysis, book a free ticket to our Virtual Trade Show, or schedule an online demo for a deeper insight in our instruments.


Virtual Trade Show