Page 45 - Application Handbook - TOC

Sum parameter – Total Organic Carbon
TOC- determination in algal biomass –
suspension method
SCA-130-401
The excessive global CO 2 emissions from the
burning of fossil fuels (for instance in power
plants) causes the search for climate-friendly
uses of carbon dioxide.
One of the approaches for environmentally
sound recycling is to convert the emitted CO 2
into biomass using photobioreactors.
The CO 2 gas is introduced into the
photobioreactor in order to be used for the
growth of algae. The biomass, or algae, can
be used in many different application areas:
in the cosmetics industry, the construction
industry, and the food segment, in agriculture
as fertilizer or for energy utilization.
■ Test methods for implementation
The efficiency of the photobiorectors and the
yield of growth are continuously monitored.
To this end, various methods are available,
including the determination of dry mass
(gravimetric) or the photometric determination
of chlorophyll (by absorption). These methods
either require a high expenditure in terms of
time and personnel, or they are nonspecific
and inaccurate.
■Innovative methods
To determine the biomass in the
photobioreactor, a TOC analyzer was used.
The carbon content of the ‘algal soup’ is
directly proportional to the biomass.
■ TOC Measurement method
Depending on the type of algae used in the
reactor, either the difference method or the
direct method (NPOC) is suitable. In both
cases, one should test which method will
most accurately detect each particular type of
algae. This can be compared with the results
of the reference method.
Information on the analysis:
 calibration of the TC/NPOC and the IC
parameters via the automated dilution
function
 sample is generally measured undiluted
 injection volume: 90 µL
 at least 3 to 5 injections for statistical
confidence
 rinse several times, depending on the
sample