Metrohm 873 Biodiesel Rancimat User manual

873 Biodiesel Rancimat
Manual
8.873.8003EN

Metrohm AG
CH-9101 Herisau
Switzerland
Phone [phone]
Fax [phone]
[email protected]
www.metrohm.com
873 Biodiesel Rancimat
Manual
8.873.8003EN 03.2009 jb/ars

Teachware
Metrohm AG
CH-9101 Herisau
[email protected]
This documentation is protected by copyright. All rights reserved.
Although all the information given in this documentation has been checked
with great care, errors cannot be entirely excluded. Should you notice any
mistakes please send us your comments using the address given above.

￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭ Table of contents
873 Biodiesel Rancimat ￭￭￭￭￭￭￭￭ III
Table of contents
1Introduction 1
1.1 Instrument description ......................................................... 1
1.2 Rancimat method ................................................................. 2
1.3 About the documentation ................................................... 3
1.3.1 Symbols and conventions ........................................................ 3
1.4 Safety instructions ................................................................ 4
1.4.1 General notes on safety ........................................................... 4
1.4.2 Electrical safety ........................................................................ 5
1.4.3 Flammable solvents and chemicals ........................................... 6
1.4.4 Recycling and disposal ............................................................. 6
2Overview of the instrument 7
3Installation 10
3.1 Setting up the instrument .................................................. 10
3.1.1 Packaging .............................................................................. 10
3.1.2 Checks .................................................................................. 10
3.1.3 Location ................................................................................ 10
3.2 Mounting accessories ......................................................... 10
3.2.1 Mounting accessories for the internal air supply ..................... 10
3.2.2 Mounting accessories for the external air supply .................... 13
3.2.3 Equipping the reaction and measuring vessels ........................ 13
3.2.4 Inserting vessels / Establishing tubing connections ................. 16
3.2.5 Mounting the exhaust collection tube (optional accesso-
ries) ....................................................................................... 16
3.3 Mains connection ............................................................... 17
3.3.1 Checking the mains voltage ................................................... 17
3.3.2 Replacing fuses ...................................................................... 18
3.3.3 Mains cable and mains connection ........................................ 18
3.3.4 Switching the instrument on/off ............................................ 19
3.4 Connecting a PC ................................................................. 19
3.4.1 Connecting the 873 Biodiesel Rancimat and the PC ............... 19
3.4.2 Installing the software ........................................................... 19
3.4.3 Carrying out basic settings ..................................................... 21
4Operation 24
4.1 Fundamentals of operation ............................................... 24
4.1.1 Starting and exiting the program ........................................... 24
4.1.2 Terms .................................................................................... 25
4.1.3 Control window .................................................................... 25
4.1.4 Results window ..................................................................... 27
4.1.5 File types ............................................................................... 30

Table of contents ￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭
IV ￭￭￭￭￭￭￭￭ 873 Biodiesel Rancimat
4.1.6 Context-sensitive menus ........................................................ 31
4.1.7 Mouse functions .................................................................... 31
4.1.8 Help ...................................................................................... 32
4.2 Instrument and Program Settings ..................................... 33
4.2.1 Establishing the instrument communication ........................... 33
4.2.2 Managing access rights ......................................................... 34
4.2.3 Timer ..................................................................................... 37
4.2.4 Gas flow control .................................................................... 39
4.2.5 Recording the temperature .................................................... 40
4.2.6 Optimizing program and database ......................................... 41
4.3 Program information ......................................................... 42
4.3.1 Instrument information .......................................................... 42
4.3.2 Status overview ..................................................................... 44
4.3.3 Displaying, filtering and deleting event overview .................... 45
4.4 Calibration functions .......................................................... 48
4.4.1 Determining cell constants ..................................................... 48
4.4.2 Determining Delta T .............................................................. 50
4.5 Methods .............................................................................. 55
4.5.1 Managing methods ............................................................... 55
4.5.2 Parameter description ............................................................ 60
4.6 Determinations ................................................................... 75
4.6.1 Preparing the instrument and the accessories ......................... 76
4.6.2 Preparing the determination .................................................. 77
4.6.3 Starting the determination ..................................................... 79
4.6.4 Cleaning the instrument and accessories ................................ 80
4.6.5 Adjusting the method parameters during the determina-
tion ....................................................................................... 81
4.6.6 Stopping the determination manually .................................... 81
4.6.7 Status of the live curve ........................................................... 82
4.7 Results ................................................................................. 83
4.7.1 Determination overview ......................................................... 83
4.7.2 Determination and method data ............................................ 99
4.7.3 Graph and reevaluation ....................................................... 108
4.7.4 Extrapolation ....................................................................... 113
4.7.5 Recalculating a determination .............................................. 117
4.7.6 Printing and exporting data ................................................. 124
4.7.7 Program settings ................................................................. 131
4.7.8 Arranging windows ............................................................. 137
4.8 GLP functions .................................................................... 138
4.8.1 General information on GLP and validation .......................... 138
4.8.2 GLP monitoring ................................................................... 138
4.8.3 GLP status ........................................................................... 140
4.8.4 Carrying out GLP tests ......................................................... 141
4.8.5 GLP results .......................................................................... 151

￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭ Table of contents
873 Biodiesel Rancimat ￭￭￭￭￭￭￭￭ V
5Handling and maintenance 155
5.1 General information ......................................................... 155
5.1.1 Care .................................................................................... 155
5.1.2 Maintenance by Metrohm Service ........................................ 155
5.2 Replacing the dust filter .................................................. 155
5.3 Regenerating or replacing the molecular sieve ............. 156
5.4 Self test when switching on ............................................ 156
5.5 Quality Management and validation with Metrohm .... 157
6Troubleshooting 159
6.1 Problems ........................................................................... 159
7Technical specifications 165
7.1 General data ..................................................................... 165
7.2 Temperature regulation and measurement ................... 165
7.3 Conductivity measurement .............................................. 166
7.4 Gas flow regulation .......................................................... 166
7.5 GLP test set ....................................................................... 167
7.6 RS-232 interface ............................................................... 167
7.7 Mains connection ............................................................. 167
7.8 Safety specification .......................................................... 168
7.9 Electromagnetic compatibility (EMC) ............................. 168
7.10 Ambient temperature ...................................................... 168
7.11 Housing ............................................................................. 169
8Conformity and warranty 170
8.1 Declaration of Conformity ............................................... 170
8.2 Quality Management Principles ...................................... 171
8.3 Warranty (guarantee) ....................................................... 172
9Accessories 173
9.1 Scope of delivery .............................................................. 173
9.2 Optional accessories ........................................................ 180
Index 183

Table of figures ￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭
VI ￭￭￭￭￭￭￭￭ 873 Biodiesel Rancimat
Table of figures
Figure 1 Measuring arrangement (schematic representation) ........................... 3
Figure 2 Front 873 Biodiesel Rancimat ............................................................ 7
Figure 3 Rear 873 Biodiesel Rancimat .............................................................. 8
Figure 4 Mounting accessories for the air supply (rear of the instrument) ...... 11
Figure 5 Equipping the reaction and measuring vessels ................................. 14
Figure 6 Equipping the reaction vessel for determining Delta T ...................... 51
Figure 7 Accessories for GLP test Temperature ............................................ 141

￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭ 1 Introduction
873 Biodiesel Rancimat ￭￭￭￭￭￭￭￭ 1
1 Introduction
1.1 Instrument description
The 873 Biodiesel Rancimat is a PC-controlled measuring device for deter-
mining the oxidation stability of biodiesel and biodiesel blends (mixture of
biodiesel and conventional diesel fuel) according to the standard
EN 14112.
It is equipped with two heating blocks each with 4 measuring positions
(channels). Every block can be heated individually, i.e. 4 samples can each
be measured at 2 different temperatures or 8 samples at the same temper-
ature. The measurements at the individual measuring positions can be
started individually for this.
Operation of the 873 Biodiesel Rancimat is realized completely via a PC
connected to the RS-232 interface using the control and evaluation program
873 Biodiesel Rancimat. Up to 4 instruments can be connected to each
PC, hence allowing a maximum of 32 samples to be analyzed. The evaluation
algorithm of the PC program determines the break point of the Rancimat
curve fully automatically and hence the induction time. Besides the induc-
tion time, the so-called stability time, i.e. the time duration until attaining
a defined conductivity change, can also be determined. In the case of con-
ductivity changes (stages) which do not have anything to do with the
autoxidation, the evaluation can be interrupted for definite time intervals.
The results determined can be processed further by computer.
Each Rancimat curve can also be evaluated manually. A PC-supported tan-
gential method is available for this, in which you can position the tangents
anywhere on your curves. This makes evaluations possible in extreme cases
as well.
The results of the determinations are saved in a database together with all
methods and determination data. Determinations can be searched for, sor-
ted, filtered, exported and printed in the program part for the results display.
Besides the graphic display of single and multiple curves, recalculation with
altered parameters and extrapolation of the results to a definite temperature
is also possible.
GLP (Good Laboratory Practice) and instrument validation are becoming
increasingly important. The 873 Biodiesel Rancimat enables GLP tests for
temperature, conductivity and gas flow measurement. You determine
whether and which tests have to be carried out. You can also specify the
time interval between the tests as well as the requirements regarding accu-
racy. If the GLP function has been selected, each result report will receive a
comment stating whether the GLP tests have been fulfilled. Metrohm offers

1.2 Rancimat method ￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭
2￭￭￭￭￭￭￭￭ 873 Biodiesel Rancimat
a GLP test set to carry out these tests (see Optional accessories, page
180).
1.2 Rancimat method
Biodiesel, also referred to as RME (rape seed methyl ester) or FAME (fatty
acid methyl esters), is usually obtained from oil seeds and used in the motor
vehicle area either in pure form or as a mixture with conventional diesel fuel.
As is the case with the natural oils, the fatty acid methyl esters obtained from
them also exhibit a relatively low level of storage stability, as they are oxidized
by atmospheric oxygen. These oxidation processes progressing slowly at
ambient temperatures are referred to as autoxidation. They start with rad-
ical reactions on unsaturated fatty acids and undergo a process involving
multiple stages resulting in diverse decomposition products, in particular
peroxides as primary oxidation products and alcohols, aldehydes and car-
boxylic acids as secondary oxidation products.
With the Rancimat method, the sample is exposed to an air flow at a
constant temperature between 50…220 °C (see Figure 1, page 3). Highly
volatile, secondary oxidation products (for the most part formic acid) are
transferred into the measuring vessel with the air flow, where they are
absorbed in the measuring solution (distilled water). Here the conductivity
is continuously registered. The organic acids can thus be detected by increas-
ing the conductivity. The time until occurrence of these secondary reaction
products is referred to as the induction time or induction period, which is a
good indicator for the oxidation stability.
The Rancimat method has been developed as an automated variant to the
extremely complex AOM (active oxygen method) for determining the induc-
tion time of fats and oils. This method has become established over the
course of time, also being used for derivatives of oils and fats. It has mean-
while become an integral element of various national and international
standards for biodiesel and biodiesel mixtures, e.g. EN 14112 and
ASTM 6751.

￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭ 1 Introduction
873 Biodiesel Rancimat ￭￭￭￭￭￭￭￭ 3
Measuring
vessel
Conductivity
measuring cell
Measuring
solution
Reaction vessel
Sample
Heating block
Figure 1 Measuring arrangement (schematic representation)
1.3 About the documentation
Caution
Please read through this documentation carefully before putting the
instrument into operation. The documentation contains information and
warnings which have to be followed by the user in order to ensure safe
operation of the instrument.
1.3.1 Symbols and conventions
The following symbols and styles are used in this documentation:
Cross-reference to figure legend
The first number refers to the figure number, the sec-
ond to the instrument part in the figure.
Instruction step
Carry out these steps in the sequence shown.
Method Dialog text, parameter in the software
File ▶ New Menu or menu item

1.4 Safety instructions ￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭
4￭￭￭￭￭￭￭￭ 873 Biodiesel Rancimat
[Next] Button or key
Warning
This symbol draws attention to a possible life hazard
or risk of injury.
Warning
This symbol draws attention to a possible hazard due
to electrical current.
Warning
This symbol draws attention to a possible hazard due
to heat or hot instrument parts.
Warning
This symbol draws attention to a possible biological
hazard.
Caution
This symbol draws attention to a possible damage of
instruments or instrument parts.
Note
This symbol marks additional information and tips.
1.4 Safety instructions
1.4.1 General notes on safety
Warning
This instrument may only be operated in accordance with the specifica-
tions in this documentation.
This instrument has left the factory in a flawless state in terms of technical
safety. To maintain this state and ensure non-hazardous operation of the
instrument, the following instructions must be observed carefully.
Hot reaction vessels
Warning
The reaction vessels can become very hot.
Avoid any contact with the hot reaction vessels. Place these in the vessel
holders provided for cooling down.

￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭ 1 Introduction
873 Biodiesel Rancimat ￭￭￭￭￭￭￭￭ 5
Flammable substances
Warning
The oven of the 873 Biodiesel Rancimat can be heated to 220 °C.
Flammable substances may ignite at these temperatures.
Adjust the maximum heating temperature of the oven to the sample being
examined.
Defective glass vessels
Warning
Caution with defective glass vessels.
An overflow of flammable samples into the heating block can be dan-
gerous.
Check the glass vessels before each use.
1.4.2 Electrical safety
The electrical safety when working with the instrument is ensured as part of
the international standard IEC 61010.
Warning
Only personnel qualified by Metrohm are authorized to carry out service
work on electronic components.
Warning
Never open the housing of the instrument. The instrument could be dam-
aged by this. There is also a risk of serious injury if live components are
touched.
There are no parts inside the housing which can be serviced or replaced
by the user.

1.4 Safety instructions ￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭
6￭￭￭￭￭￭￭￭ 873 Biodiesel Rancimat
Mains voltage
Warning
An incorrect mains voltage can damage the instrument.
Only operate this instrument with a mains voltage specified for it (see rear
panel of the instrument).
Protection against electrostatic charges
Warning
Electronic components are sensitive to electrostatic charges and can be
destroyed by discharges.
Always pull the mains cable out of the mains connection socket before
connecting or disconnecting electrical appliances on the rear panel of the
instrument.
1.4.3 Flammable solvents and chemicals
Warning
All relevant safety measures are to be observed when working with flam-
mable solvents and chemicals.
￭Set up the instrument in a well-ventilated location (e.g. laboratory
flue).
￭Keep all sources of flame far from the workplace.
￭Clean up spilled fluids and solids immediately.
￭Follow the safety instructions of the chemical manufacturer.
1.4.4 Recycling and disposal
This product is covered by European Directive 2002/96/EC, WEEE – Waste
from Electrical and Electronic Equipment.
The correct disposal of your old equipment will help to prevent negative
effects on the environment and public health.
More details about the disposal of your old equipment can be obtained from
your local authorities, from waste disposal companies or from your local
dealer.

￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭ 2 Overview of the instrument
873 Biodiesel Rancimat ￭￭￭￭￭￭￭￭ 7
2 Overview of the instrument
873
Biodiesel Rancimat
11
10
9
8
7
6
5
4
3
2
1
Figure 2 Front 873 Biodiesel Rancimat
1Pilot lamp
Lights up when the instrument is switched on.
2Gas flow display
Flashes when the gas flow is switched on.
Lights up when the gas flow has been
reached.
3Temperature display
Flashes when the heating is switched on.
Lights up when the temperature has been
reached.
4Error display (red)
Lights up or flashes when a fault has occurred
in the instrument (see Troubleshooting Chap-
ter).
5Instrument number display
Indicates the number of the instrument.
Lights up if the instrument is registered.
Flashes (all LEDs) if the connection to the PC
is interrupted.
6FEP tubing 250 mm (6.1805.080)
For supplying air into the reaction vessel.
7Measuring vessel cover (6.0913.130)
Contains an integrated conductivity measur-
ing cell.
8Glass measuring vessel (6.1428.030)
9Iso-Versinic® tubing (6.1839.000)
For connecting the reaction vessel to the
measuring vessel. A fluoroelastomer.
10 Reaction vessel cover (6.2753.107)

￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭
8￭￭￭￭￭￭￭￭ 873 Biodiesel Rancimat
11 Reaction vessel (6.1429.040)
Molecular sieve flask
Filter
Air out
2
Air/N in
Pt 100
RS 232
WARNING - Fire Hazard -
with the same type and rating of fuse
For continued protection replace only
100-115V: 4A(TH)
Fuse
Made by Metrohm Herisau Switzerland
From
flask
To
flask
220-240V: 2A(TH)
Type:
Nr.:
U:
f:
S:
14
3
45678 9 10 11 12 13 15 16 17 18 19 20
1
2
Figure 3 Rear 873 Biodiesel Rancimat
1Collection tube holder
For fastening the optional exhaust collection
tube (6.2757.000).
2Electrode connector
For connecting the conductivity measuring
cell integrated in the measuring vessel cover
(2-
7 ).
3Air supply connection
For connecting the FEP tubing 250 mm
(2-
6 ).
4Mains switch
For turning the instrument on and off.
I = ON / 0 = OFF.
5Mains connection socket
For important information on the mains con-
nection, see Chapter 3.3.
6Fuse holder
Replacing fuses, see Chapter 3.3.2.
7Type plate
Contains specifications concerning mains
voltage and serial number.
8RS-232 connector
For connecting the PC.
9Pt100 connector
For connecting an external temperature sen-
sor.
10 Drying flask cover (6.1602.145)
Cover for the drying flask.
11 Drying flask (6.1608.050) 12 Flask holder
For fastening the drying flask.

￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭ 2 Overview of the instrument
873 Biodiesel Rancimat ￭￭￭￭￭￭￭￭ 9
13 FEP tubing 250 mm (6.1805.080)
For supplying the air from the internal pump
to the drying flask.
14 FEP tubing 250 mm (6.1805.080)
For supplying the air from the drying flask to
the reaction vessel (2-
11 ).
15 "From Flask" connection 16 "Air/N2 in" connection
17 FEP tubing 130 mm (6.1805.010)
For connecting the Air out connection to the
Air/N2 in connection during normal opera-
tion with the internal air pump.
18 "Air out" connection
19 "To Flask" connection 20 Dust filter (6.2724.010)

3.1 Setting up the instrument ￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭
10 ￭￭￭￭￭￭￭￭ 873 Biodiesel Rancimat
3 Installation
3.1 Setting up the instrument
3.1.1 Packaging
The instrument is supplied in highly protective special packaging together
with the separately packed accessories. Keep this packaging, as only this
ensures safe transportation of the instrument.
3.1.2 Checks
Immediately after receipt, check whether the shipment has arrived complete
and without damage by comparing it with the delivery note.
3.1.3 Location
The instrument has been developed for operation indoors and may not be
used in explosive environments.
Place the instrument in a location of the laboratory suitable for operation
and free of vibrations, if possible protected from corrosive atmospheres and
contamination by chemicals.
The instrument should be protected against excessive temperature fluctua-
tions and direct sunlight.
Note
In order to improve accessibility for the measuring positions, the instru-
ment can be placed on the optionally available 6.2059.000 turning ring.
3.2 Mounting accessories
3.2.1 Mounting accessories for the internal air supply
The gas in the Biodiesel Rancimat is normally supplied using the internal
air pump, which sucks in laboratory air. For air supply and air purifica-
tion, the following accessories must be mounted on the rear of the Biodiesel
Rancimat:

￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭ 3 Installation
873 Biodiesel Rancimat ￭￭￭￭￭￭￭￭ 11
Molecular sieve flask
Filter
Air out
2
Air/N in
From
flask
To
flask
8
9
10
12
11
1
2
3
654 7
Figure 4 Mounting accessories for the air supply (rear of the instrument)
1Drying flask cover (6.1602.145)
Cover for the drying flask.
2Drying flask (6.1608.050)
3Flask holder
For fastening the drying flask.
4Filter tube (6.1821.040)
5FEP tubing 250 mm (6.1805.080)
For supplying the air from the internal pump
to the drying flask.
6FEP tubing 250 mm (6.1805.080)
For supplying the air from the drying flask to
the reaction vessel (2-
11 ).
7"From Flask" connection 8Dust filter (6.2724.010)
9"To Flask" connection 10 "Air out" connection
11 FEP tubing 130 mm (6.1805.010) 12 "Air/N2 in" connection
Mount the accessories for the air supply as follows:
1Mount dust filter
￭Insert the dust filter (4- 8 ) on the connection marked with Filter on
the rear of the Biodiesel Rancimat.
￭If the laboratory air is heavily contaminated, a tubing for supplying
fresh air can be connected to the dust filter.
Note
The dust filter serves for filtering the air sucked through the air pump
and must be replaced at periodic intervals (see Chapter 5.2, page
155).

3.2 Mounting accessories ￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭
12 ￭￭￭￭￭￭￭￭ 873 Biodiesel Rancimat
2Mount drying flask
Caution
Do not fill the hot molecular sieve directly into the drying flask after
regeneration, as otherwise the plastic filter on the filter tube will
melt.
Wait until the molecular sieve has cooled down before filling.
￭Fill the molecular sieve into the drying flask (4-
2 ).
￭Screw the filter tube (4-
4 ) on the lower side of the drying flask cover
(4- 1 ) into the opening marked (above) with a dot.
￭Screw the drying flask cover with mounted filter tube onto the dry-
ing flask and insert in the flask holder (4-
3 ) on the rear of the
Biodiesel Rancimat.
￭Screw the one end of the FEP tubing 250 mm (4- 6 ) onto that open-
ing on the drying flask cover at the bottom of which the filter tube
is located.
￭Screw the other end of the FEP tubing onto the From flask con-
nection (4-
7 ) on the rear of the Biodiesel Rancimat.
￭Screw the one end of the second FEP tubing 250 mm (4- 5 ) onto
the second opening on the drying flask cover.
￭Screw the other end of the second FEP tubing onto the To flask
connection (4-
9 ).
Note
The molecular sieve serves for adsorbing interfering oxidizing gases
as well as water from the sucked in air. You can regenerate it in the
drying oven at +140…+180 °C for 24 to 48 h (see Chapter 5.3, page
156).
3Mount the FEP tubing for the supply air
￭Screw the one end of the FEP tubing 130 mm (4- 11 ) onto the Air
out connection (4-
10 ).
￭Screw the other end of the FEP tubing onto the Air/N2 in connec-
tion (4-
12 ).