Traditional Water Quality Analysis
In order to ensure water hygiene and safety for thousands of
households, the center must deal with many different water samples
daily, including source water, treated water at different process
stages and end water. Every water sample requires a series of
analyses. The main detection parameters are: total hardness,
chloride content, residual chloride, COD (chemical oxygen demand)
plus alkalinity.
The traditional method is classical manual titration. Previously,
analysts stood by the experiment table, one hand operating the glass
titration burette, the other shaking the conical bottle in which
chemical reactions were constantly happening, observing solution
color change. Past experimental data was manually logged.
Automatic Potentiometric Titration
METTLER TOLEDO has become a welcomed new partner at the center with
a fully automatic potentiometric titration system – the T50
Excellence Titrator and the Rondo 20 fully automatic sample changer.
Twenty sample beakers are put on the sample changer, the shortcut
key is pressed and the test begins: the propeller stirrer on the
titration stand mixes the chemical substances whilst the dosing unit
begins to dispense titrant. An electrode successfully detects the
end point reaction, freeing up operators. When the test is
completed, all relevant experiment information is printed out in
order to be compliant with GLP (Good Laboratory Practice). By the
time the report is printed, the instrument has already cleaned the
detection electrode and propeller stirrer to be ready for the next
sample.
The centre periodically uses a standard substance as a sample to
examine the reliability and accuracy of each instrument. The T50
Titrator obtains precise results in every ‘trial test' with
measurement results consistently complying with standard values. The
original manual titration burettes are correct up to ±0.01 ml while
the dispensing precision of the automatic titrator can be raised to
0.05 µl. In addition, manual titration depends upon color change to
judge end points leading to errors due to operator differences.
Greater errors can occur for titration with nonapparent color change
or those generated by precipitation. Potentiometric titration
eliminates operator errors.
‘One-Click', and results are achieved efficiently, correctly and
simply.
For more information,
click
here.
About METTLER TOLEDO
METTLER TOLEDO is a leading global supplier of precision instruments
and services. The Company is the world's largest manufacturer and
marketer of weighing instruments for use in laboratory, industrial
and food retailing applications. METTLER TOLEDO also holds top-three
market positions in several related analytical instruments and is a
leading provider of automated chemistry systems used in drug and
chemical compound discovery and development. In addition, the
Company is the world's largest manufacturer and marketer of metal
detection and other end-of-line inspection systems used in
production and packaging and holds a leading position in certain
process analytics applications.
SOURCE:
Mettler-Toledo Thornton, Inc.