Laboratory equipment

BET Reactive Surface Area Analyser

Almost all biogeochemical processes are dependent on the reactive surface of the biota as well as the inorganic geological materials involved in these processes. This is no different in anthropogenically impacted environments. Quantifying the reactive surface area of biological and inorganic materials is therefore critical to accurately determine the reaction rates of biogeochemical processes. The BET Reactive Surface Area Analyser measures the reactive surface areas of substances as well as macro- and meso-porosity.

Sample requirements:

• Sample particles should not be larger than 5 mm in diameter.

• The nature of the sample (e.g. polymer, mineral, rock or organic) should be known prior to surface area analysis.

Auto-titration system

An important variable in biogeochemical processes is the number of reactive sites on the surface of biological and inorganic material. Most surfaces react via proton-exchange mechanisms, which are strongly dependent on the pH. Acid-base titrations can be used to determine the number of reactive surface sites.

One key water-quality parameter is the carbonate alkalinity. This can be determine by auto-titration methods.

Sample requirements:

• For determination of number of active surface sites, solid samples must be provided.

• For alkalinity measurement, liquid samples need to be provided in appropriate containers (e.g. LDPE bottles and the samples should not have been acidified prior to analysis).