Dissolved organic carbon

The Dissolved organic carbon or engl. dissolved organic carbon (DOC), being a part of the total organic carbon to the carbon sum parameters and refers to the dissolved forms. It is part of Dissolved organic matter ( DOM). Such particles are smaller than 0.45 microns.

LC - OCD - Liquid Chromatography - Organic Carbon Detection

LC OCD is a liquid chromatography system, which in addition to standard detectors such as UV / Vis (UV ), fluorescence (FL ), and conductivity (LF ) includes a carbon- selective detector.

DOC is determined using the Gräntzel thin film reactor, in which organic carbon is converted by wet-chemical oxidation by UV irradiation (185 nm) without the addition of an oxidising agent to carbon dioxide (CO2). The sample flows to form a thin film on a cylinder and is thereby irradiated with intensive ultraviolet light. Simultaneously, the sample film is stirred by a rotating, fitted with Teflon inner cylinder pins. This results in a substantially quantitative oxidation of the organic carbon compounds is achieved. The sample is added at the top, non-irradiated part of the reactor with dilute phosphoric acid (pH 2). The carbon dioxide thus formed from the IC is continuously stripped with nitrogen. Detecting the carbon dioxide with an infrared detector.

The method was in the years 1985-1995 at the Engler -Bunte- Institute, University of Karlsruhe together with the company - developed " Alfred Gräntzel physical equipment manufacturing " in Karlsruhe.