Economical determination of trace amounts of water – with the new 831 KF Coulometer

Precise and favorably priced – no contradiction in terms! With the 831 KF Coulometer Metrohm defines new standards in price-performance ratio. Despite its extremely favorable price, the latest member of our Karl Fischer range leaves no wishes unfulfilled. The instrument guarantees accurate and precise results, even for water contents in the lower microgram range. Its compact design, flexibility and user-friendliness are also convincing.

Economical determination of trace amounts of water – with the new ...

756 KF Coulometer

An innovative and comprehensive solution The 756 KF Coulometer continues Metrohm’s estab-
lished line of Karl Fischer instruments for the determination of low-level water contents. Despite its compactconstruction this instrument leaves no wishes unfulfilled. It comes equipped with a built-in printer and two RS 232C interfaces which allow communication with a balance, external printer and/or computer. This latest addition to the Karl Fischer range guarantees accurate
and reproducible results even for water contents in the lower micro range. The dialogue languages English, French, German, Spanish, Portuguese, Swedish and with curve showing the
Italian are standard, as is the backlit screen with its titrated water as m(H2O) in microgrammes vs. the time in seconds graphics capabilities. The screen not only provides a
clear presentation of the parameters, but also shows graphically the course of the KF determination as μg water versus time. This facilitates the assessment of the determination and is a great help in method develop ment and validation. Depending on the amount of data that are to appear on the instrument display, large or small fonts can be selected. A user list can be entered; the name selected from this list appears in the result report, which can be freely
configured by simply selecting the lines containing the desired information. Using the optional Remote Box you can connect a barcode scanner and a PC keyboard to the 756 KF Coulometer.


PDF] 756 KF Coulometer

Salt shake-up.(PLANT & EQUIPMENT)

Publication: Food Trade Review

Publication Date: 01-SEP-05

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Full-Text Online Journals Research online. Academic journals & books at Questia Online Library. Water Quality Meters Testers and meters for Laboratories for all your needs Water in Solvents From PPM to % analysis of water in organic solvents with a solid state Labcaire Systems Ltd Wide range of fume cupboards to suit most laboratory requirements COPYRIGHT 2005 Food Trade Press Ltd. With children's food salt content being closely monitored, Metrohm UK have developed a favourably priced and easy to use analytical solution for sodium analysis. In May 2003, the Food Standards Agency (FSA) announced guidelines on maximum recommended salt intakes for children. At the time, the Food Commission warned that with so much hidden salt in children's food, it would be hard for parents to achieve the targets without a significant reduction of salt in processed food. The Food and Drink Federation (FDF, representing the food industry) announced that it would work with its industry members to reduce salt content in soups and sauces by 10%. There have been mixed results in the successes of this over the last two years but one point is very clear; parents are more aware than ever before about the dangers of salt in food. Market research has shown that parents more and more read the labels on processed food packaging and demand to know exactly what they are feeding their children. It is the Sodium in salt that leads to health problems, the FSA recommend the salt intake for children ages 1-3 should be no more than 2g per day (that is 0.8g sodium per day). All food manufacturers, not just of children's food, must label the sodium content, preferably expressed per 100g. Metrohm UK can provide a simple analytical technique for sodium at a price all laboratories can afford. The determination of Na with the Na ISE represents a selective, rapid, accurate and favourably priced method (see Metrohm Application Bulletin 83/5). The 6.0501.100 glass membrane ISE is recommended for samples with a difficult matrix such as food samples. The Na ISE is connected to a Metrohm 781 pH/Ion Meter, the determinations are performed by establishing calibration curves or by carrying out standard or sample additions. For the fully automatic standard addition you need only enter the concentration of your standard and the desired number of additions, the rest is taken care of by the pH/Ion Meter. The working principle is simple, in aqueous solutions, cations are removed from the outer hydrated layer of the glass membrane and replaced by Na+ ions from the sample. This creates a potential (that can be measured) at the boundary layer between the sample solution and the membrane that depends on the activity of sodium. It is also necessary to add a Total Ionic Strength Adjustment Buffer (TISAB) which fixes the ionic strength of the sample and buffers the pH values above 9 as measurements must be carried out in alkali conditions. Difficult samples of complex matrices of vegetables, meat and fish have been recently sampled by Metrohm UK. Reproducible results were obtained by sonicating a known weight of sample in 20ml of distilled water in a sonic bath for five minutes before adding TISAB and analyzing. The total analysis time was on average less than seven minutes, a huge time saving when compared with the traditional 'ashing' technique which can take over 24 hours. Metrohm UK can provide a fast, simple and reasonably priced technique for sodium analysis in the food industry. Contact Metrohm UK on tel 01280 824 824 or visit www.metrohm.co.uk More Articles from Food Trade Review Platinum Collection.(PRODUCTS) September 01, 2005 Weight Watchers spices up its cookie range.(PRODUCTS) September 01, 2005 Snowbird logs on with new sandwich idea.(PRODUCTS) September 01, 2005 New Probiotics yoghurt.(PRODUCTS) September 01, 2005 Healthier options mean healthy profits.(PRODUCTS) September 01, 2005 Find companies classified under Chemical and fertilizer mining not elsewhere classified Find companies classified under Chemical preparations not elsewhere classified

Elimination process of fluorinated anionic surfactants

Abstract:

An elimination process of fluorinated anionic sufactants from exhausted gaseous streams, wherein the gaseous stream is put into contact with aqueous solutions having in the range from 3.5 to 13.8, the aqueous solution density being lower than 1.05 g/cm³, wherein the concentration in the aqueous solution of the fluorinated anionic surfactant removed by the gaseous stream is lower than or equal to 70 ppm.

Representative Image:

Inventors:

Ferrero, Stefano (Alessandria, IT)
Deregibus, Evasio (Alessandria, IT)
Plaque It!



Article

KF Coulometer

Precise and inexpensive no contradiction in terms!Metrohm’s 831 KF Coulometer sets new standards regarding price-performance ratio. Despite its exceptionally favorable price, the youngest mem ber of our Karl Fischer instrument range leaves no wish unfulfilled. The 831 KF Coulometer guarantees pre cise and accurate results even in the low microgram region. Its additional assets are compact construction, flex ibility and easy operation.

831 KF Coulometer

How much Vitamin C is in my orange juice?

Introduction to Vitamin C Vitamin C is the L-enantiomer of ascorbic acid. Our body cannot synthesize and store vitamin C. Therefore it is essential to obtain it from the food we are consuming daily. Ascorbic acid and its sodium, potassium and calcium salts possess antioxidant properties. They can prevent reactive oxygen species (ROS, for example hydrogen peroxide) from damaging our body cells by taking up their reactive electrons. Drinks, fruit and vegetable juices are natural sources of vitamin C. The content of vitamin C of vegetables, juices and other food can be determined by titration, ion chromatography or polarography.

Voltammetric analysis of vitamin C The analysis by polarography is very selective as other reducing or oxidizing substances do not interfere. By using a 797 VA Computrace various polarographic and voltammetric methods are at hand and moreover you are given all the necessary electrodes for performing hundreds of applications. In the case of the vitamin C determination in orange juice no sample preparation steps are necessary. The analysis is done by differential pulse polarography (DPP) at a dropping mercury electrode (DME). Just choose the method in the built-in database of your 797 VA Computrace. With a single mouse click all settings are done and you can start measuring.

Product information MVA-2 system intended for partly automated routine analysis and consisting of the 797 VA Computrace and two 800 Dosinos. MVA-2 Options MVA-3 system for fully automated analysis of small series of samples consisting of the 797 VA Computrace, a 813 Compact Autosampler, two 800 Dosinos, a 731 Relay Box and two 772 Pump Units MVA-3 Send me product information!

Get more information Order our free Monograph Practical Voltammetry (8.757.500X) in English or German. Find more application details in our Application Bulletin 98 (Info Center) Applications for Voltammetry and Polarography Overview of Metrohm VA Instruments Send us your request!

Tips Up to 18 samples are easily processed fully automatically by the MVA-3 system. Validation: For the Validation of Metrohm VA instruments using Standard Operating Procedures see our Application Bulletin 276 (Info Center). If you already have a titration system (Titrino or Titrando), then you can determine the vitamin C content according to the methods described in our Food PAC.

Bio diesel analysis and European Standard EN14214

A Metrohm UK product story

Edited by the Laboratorytalk editorial team May 4, 2006

Manufacture and use of fatty acid methyl esters (Fame), has huge implications for the environment; biodiesel is a clean burning alternative fuel, produced from domestic, renewable resources

Bio diesel contains no petroleum, but it can be blended at any level with petroleum diesel to create a bio diesel blend.
It can be used in compression-ignition (diesel) engines with little or no modifications.
Bio diesel is simple to use, biodegradable, non-toxic, and essentially free of sulphur and aromatics.
Bio diesel is made through a chemical process called transesterification whereby the glycerine is separated from the fat or vegetable oil.
The process leaves behind two products - methyl esters (the chemical name for bio diesel) and glycerine (a valuable by-product usually sold to be used in soaps and other products).
Fuel-grade bio diesel must be produced to strict industry specifications (ASTM D6751) in order to insure proper performance.
Bio diesel is the only alternative fuel to have fully completed the health effects testing requirements of the 1990 Clean Air Act Amendments.
Bio diesel that meets ASTM D6751 and is legally registered with the Environmental Protection Agency is a legal motor fuel for sale and distribution.
Metrohm can offer a solution to many of the analytical requirements listed in European Standard EN14214, namely:.
Oxidative stability rancimat method.
Acid value potentiometric titration.
Iodine value potentiometric titration.
Water content Karl Fischer.
Viscosity rotational viscometers.
Oxidative Stability.
The Metrohm Rancimat 743 method for measuring the oxidative stability of fatty acid methyl esters is determined according to DIN EN 14112.
In this method the highly volatile organic acids produced by autoxidation are absorbed in water and used to indicate induction time.
With the simple to use 743 Rancimat, the determination takes place at a highly sophisticated level.
Eight measuring positions in two independent heating blocks.
Individual start on each position.
Comprehensive control by PC.
Up to four Rancimat measuring blocks per PC - and therefore up to 32 samples at up to eight different temperatures.
Integrated GLP Test.
Titrations for bio diesel.
As listed in European Standard EN14214, Bio diesel manufacturers are required to determine acid value and iodine number by titration.
Using Metrohm autotitrators these methods have been perfected over the years and can be found in Metrohm Application Bulletin 141- Analysis of Edible Oils and Fats.
Iodine number.
For this analysis the following are required.
Metrohm Autotitrator, either a Titrando or a Titrino Model.
Combined Platinum Electrode e.g Pt Titrode or Pt Ring Electrodes.
The titration is a dynamic (DET U) Back titration with 0.1M Sodium Thiosulphate.
The sample is dissolve sample in Glacial Acetic Acid.
And added are 25ml of reaction solution and 10ml catalyst.
(specified in Bulletin).
Store in dark for five minutes.
Add 15ml KI solution, DI water and back-titrate to excess of iodine with 0.1M Na2S2O3.
At same time run a blank without sample.
The titrator automatically carries out the calculation g iodine/100g =(ml of thiosulphate for blank - ml thiosulphate for sample) x 1.269/ sample size (1.269=equivalent weight of iodine).
Acid Number.
You will need.
Autotitrator- Titrando or Titrino Models.
Solvotrode Non-aqueous pH electrode with LiCl sat.
in ethanol electrolyte.
0.1M KOH in isopropanol.
Solvent mixture ethanol/diethyl ether 1:1.
Weigh out 5-10 g sample, dissolve in 50ml solvent mixture.
Dynamic (DET U) Titration with KOH.
AN mgKOH/g = ml 0.1M KOH x 5.61/ sample size (5.61=equivalent weight KOH).
Karl Fischer moisture analysis.
EN14214/ EN ISO 12937 states that water determination should be by coulometric KF titration method.
Metrohm can offer a choice of two Coulometers, either the 831 or the 756 models.
In some cases the addition of a solubility promoter (chloroform or propanol) is recommended to improve solubility.

Tin cans - a possible source of contamination of canned food

Food preservation Canning food is a good method of preservation which uses no chemical preservatives and is therefore widely used. Usually cans consist of tin plate which is tin coated steel. Tin is necessary to prevent iron from being corroded by the canned food. Unfortunately tin itself can slowly transfer into the food. The amount of tin taken up by the canned food is affected by many factors. Tin may cause stomach upsets and irritates the digestive tract of sensitive people when present in high concentrations. Fortunately there are no long-term effects due to normal intakes from tin in the food even if it is present in higher levels. An organic compound can be used to line the cans. These fully lacquered cans strongly reduce the levels of tin as long as this protective layer remains undamaged. Nevertheless a new problem arises due to the bisphenol-A which is contained in the lacquer paint and has a potential to interact (endocrine disrupter) with our hormone system.

Voltammetric analysis of tin Differential pulse anodic stripping voltammetry (DPASV) in combination with a hanging mercury drop electrode (HMDE) is an analysis method for determining the concentration of tin in canned food. Prior to the analysis the canned food has to be digested by means of a mixture of concentrated mineral acids. Lead, which was used with tin until lately as a solder (also for cans), can also be determined with the described method from Metrohm. There are a variety of methods described which allow a successful determination of lead even in presence of other metal ions as thallium or cadmium. A specification between Sn(II) and Sn(IV) is also possible. The anodic stripping voltammetry can be carried out on a MVA-2 system. The heart of this system is a 797 VA Computrace enriched with the unbeatable Dosino technique for liquid handling. For your convenience, the methods for the tin and lead determination are already implemented in Metrohm's 797 VA Computrace. Just press the button and start measuring.

Product information MVA-2 system intended for partly automated routine analysis and consisting of the 797 VA Computrace and two 800 Dosinos. MVA-2 Options MVA-3 system for fully automated analysis of small series of samples consisting of the 797 VA Computrace, a 813 Compact Autosampler, two 800 Dosinos, a 731 Relay Box and two 772 Pump Units MVA-3 Send me product information!

Get more information Order our free Monograph Practical Voltammetry (8.757.500X) in English or German. Find more application details in our Application Bulletin 176 (Info Center) Applications for Voltammetry and Polarography Overview of Metrohm VA Instruments

Tips Automation: Up to 18 samples are easily processed fully automatically by the MVA-3 system. Sample preparation: How digestion is done Validation: For the Validation of Metrohm VA instruments using Standard Operating Procedures see our Application Bulletin 276 (Info Center).

Trace analysis and metal speciation with voltammetry

Voltammetry instruments are favorably priced and compact, yet great in their detection capabilities. You can analyze water, environmental samples or ultrapure chemicals!

Convincing applications Total metal concentration and speciation: Apart from the determination of the total concentration, which is normally obtained with spectroscopic methods, voltammetry allows to distinguish the different oxidation stages of metal ions or differentiate between free and bound metal ions as well as to specify the biological availability of heavy metals. This makes voltammetry into an essential tool for environmental analysis. Comparable insights can only be gained by spectroscopy after complicated separation of the metal species. Its compact size means that the VA instrument can also be used in mobile laboratories. Samples with high ionic concentration are no problem for voltammetry. Organics and anions: Not only metals but also various organic compounds can be determined by voltammetry. VA techniques are used in organic chemistry and in the pharmaceutical industry. Some special anions can also be determined by voltammetry. The determination of environmentally relevant anions like cyanide, sulfide, nitrite or nitrate is particularly interesting Voltammetric trace analysis has extremely low detection limits has no problems with high salt concentrations allows speciation differentiates between free and complexed metal ions can also analyze non-metals such as anions or organics. Typical Detection Limits (1 ppt = 1 part per trillion = 1 ng/kg) Antimony Sb(III), Sb(V) 200 ppt e.g. Application Bulletin 74 Arsenic As(III), As(V) 100 ppt e.g. Application Bulletin 226 Bismuth Bi 500 ppt e.g. Application Bulletin 74 Cadmium Cd 50 ppt e.g. Application Bulletin 231 Chromium Cr(III), Cr(VI) 25 ppt e.g. Application Bulletin 116 Cobalt Co 50 ppt e.g. Application Bulletin 231 Copper Cu 50 ppt e.g. Application Bulletin 231 Iron Fe(II), Fe(III) 50 ppt e.g. Application Bulletin 123 Lead Pb 50 ppt e.g. Application Bulletin 231 Mercury Hg 100 ppt e.g. Application Bulletin 96 Molybdenum Mo 50 ppt e.g. Application Bulletin 146 Nickel Ni 50 ppt e.g. Application Bulletin 231 Platinum Pt 0.1 ppt e.g. Application Bulletin 220 Rhodium Rh 0.1 ppt e.g. Application Bulletin 220 Thallium Tl 50 ppt e.g. Application Bulletin 231 Tungsten W 200 ppt e.g. Application Note V-65 Uranium U 25 ppt e.g. Application Bulletin 266 Zinc Zn 50 ppt e.g. Application Bulletin 231 The applications can be downloaded from the Info Center (registration required). Download of bulletins: English, French, German.

Products: Instruments, Software, Electrodes > 10 good reasons why you should consider the Metrohm 797 VA Computrace instead of an AAS or ICP MVA: Metrohm VA Systems Metrohm VA Systems VA Modules 797 VA Computrace 863 Compact Autosampler Software VA Database 2.2 Instruments for Sample Preparation 705 UV Digester Electrodes for Voltammetry > Which electrode for which application?

Get more information Monograph “Introduction to Polarography and Voltammetry” Monograph "Practical Voltammetry" Which electrode for which application? Applications for Trace Analysis by Voltammetry Metrohm Information article about the 797 VA Computrace

NIO electrode for the titrimetic determination of non-ionic surfactants by Metrohm AG View catalog online Catalog: NIO electrode for the titrimetic determination of non-ionic surfactants Company/Brand: Metrohm AG Flippable HTML catalog PDF catalog Flippable Flash catalog Visitor statistics
Metrohm AG Contact Information Metrohm AG Oberdorfstr. 68 CH-9100 Herisau Phone +41 71 353 85 85 Fax +41 71 353 89 01 http://www.metrohm.com/

Technique for analysis of biodiesel

The manufacture and use of fatty acid methyl esters (Fame), has huge implications for the environment; biodiesel is the name of a clean burning alternative fuel, produced from renewable resources

Biodiesel contains no petroleum, but it can be blended at any level with petroleum diesel to create a biodiesel blend.
It can be used in compression-ignition (diesel) engines with little or no modifications.
Biodiesel is simple to use, biodegradable, nontoxic, and essentially free of sulphur and aromatics.
Biodiesel is made through a chemical process called transesterification whereby the glycerin is separated from the fat or vegetable oil.
The process leaves behind two products - methyl esters (the chemical name for biodiesel) and glycerin (a valuable byproduct usually sold to be used in soaps and other products).
Fuel-grade biodiesel must be produced to strict industry specifications (ASTM D6751) in order to insure proper performance.
Biodiesel is the only alternative fuel to have fully completed the health effects testing requirements of the 1990 Clean Air Act Amendments.
Biodiesel that meets ASTM D6751 and is legally registered with the US Environmental Protection Agency is a legal motor fuel for sale and distribution.
Metrohm can offer a solution to many of the analytical requirements listed in Euopean Standard EN14214, namely, .
oxidative stability Rancimat method.
Acid value potentiometric titration.
Iodine value potentiometric titration.
Water content Karl Fischer.
Oxidative stability.
The Metrohm Rancimat 743 method for measuring the oxidative stability of fatty acid methyl esters is determined according to DIN EN 14112.
In this method the highly volatile organic acids produced by autoxidation are absorbed in water and used to indicate induction time.
With the simple to use 743 Rancimat, the determination takes place at a highly sophisticated level, eight measuring positions in two independent heating blocks.
Individual start on each position.
Comprehensive control by PC.
Up to four Rancimat measuring blocks per PC - and therefore up to 32 samples at up to eight different temperatures.
Integrated GLP test.
Titrations for biodiesel.
As listed in Euopean Standard EN14214, Biodiesel manaufacturers are required to determine acid value and iodine number by titration.
Using Metrohm autititrators these methods have been perfected over the years and can be found in Metrohm Application Bulletin 141- Analysis of Edible Oils and Fats.
Iodine number.
For this anlysis the following are required.
Metrohm Autotitrator, either a Titrando or a Titrino model.
Combined platinum electrode, eg Pt Titrode or Pt ring electrodes.
The titration is a dynamic (Det U) back titration with 0.1M sodium thiosulphate.
The sample is dissolve sample in glacial acetic acid.
And added are 25ml of reaction solution and 10ml catalyst.
(specified in Bulletin).
Store on dark for five minutes.
Add 15ml KI solution, DI water and back-titrate to excess of iodine with 0.1M Na2S2O3.
At same time run a blank without sample.
The titrator automatically carries out the calculation.
g iodine/100g =(ml of thiosulphate for blank - ml thiosulphate for sample) x 1.269/ sample size.
(1.269=equivalent weight of iodine).
Acid number.
You will need.
Autotitrator- Titrando or Titrino models.
Solvotrode Non-aqueous pH electrode with LiCl sat in ethanol electrolyte.
0.1M KOH in isopropanol.
Solvent mixture ethanol/diethyl ether 1:1.
Weigh out 5-10 g sample, dissolve in 50ml solvent mixture.
Dynamic (DET U) Titration with KOH.
AN mgKOH/g = ml 0.1M KOH x 5.61/ sample size.
(5.61=equivalent weight KOH).
Karl Fischer moisture analysis.
EN14214/ EN ISO 12937 states that water determination should be by coulometric KF titration method.
Metrohmcan offer a choice of two coulometers.
either the 831 or the 756 models.
In some cases the addition of a solubility promoter (chloroform or propanol) is recommeded to improve solubilty.

Photometry, Application Bulletin Metrohm

AB-140 Titrimetric determination of sulfate This Bulletin describes three potentiometric and one photometric titration method for the determination of sulfate. Which indication method is the most suitable depends above all on the sample matrix and is illustrated with examples. Method 1: Precipitation as barium sulfate and back-titration of the Ba2+ excess with EGTA. The ion-selective calcium electrode is used as indicator electrode. Method 2: As in method 1, but with the electrode combination tungsten/platinum. Method 3: Precipitation titration in semi-aqueous solution with lead perchlorate using the ion-selective lead electrode as indicator electrode. Method 4: Photometric titration with barium perchlorate, thorin indicator and the 662 Photometer or 525 nm Spectrode. Particularly suitable for micro determinations! AB-094 Potentiometric and photometric analysis of honey Simple methods are described for the analysis of honey that permit any damage or adulteration to be detected. The pH and total acids are determined together with the lactone and formol numbers. The determination of the hydroxymethylfurfurol content (HMF) is carried out photometrically. A separate method exists for the determination of water by the Karl Fischer method. AB-093 Potentiometric analysis of cadmium plating baths This Bulletin describes titrimetric methods for the determination of cadmium, free sodium hydroxide, sodium carbonate and total cyanide. The free cyanide can be calculated from the total cyanide and the Cd content. AB-063 Determination of silicon, calcium, magnesium, iron and aluminum in cements by photometric titration of the solubilized product The insoluble silicon dioxide remaining after dissolution of cement is determined gravimetrically. The calcium, magnesium, iron and aluminium in the filtrate are determined by photometric EDTA (0.1 mol/L) titration using a 662 Photometer. The following instructions conform to the analytical methods of 11 November 1981 recommended by the Association of Austrian Cement Manufacturers. AB-049 Colorimetric determination of copper Application Bulletin no. 43 describes the polarographic determination of copper. For copper concentrations of 10 mg/L and below, however, colorimetric methods are also used, particularly in water analysis. The method using sodium diethyldithiocarbamate can be employed down to a minimum limit of 0.01 mg/L Cu, but suffers from the drawback that the determination can also be affected by other metal ions. The method using neocuproine has a minimum concentration limit of 0.1 mg/L Cu, but has the advantage of being unaffected by ions of other metals. AB-033 Determination of the total, calcium and magnesium hardness of water samples by photometric titration This Bulletin describes the determination of the total, calcium and magnesium hardness of water using the light-guide photometer and/or Spectrode. AB-030 Photometric determination of chromium(VI) With chromates and dichromates, diphenylcarbazide gives a red-violet coloration which can be measured with the 662 Photometer. The reaction is extremely sensitive, enabling concentrations of ρ(Cr) <> In electroplating effluents, chromium occurs as the Cr(VI) ion. It must first be reduced to Cr(III) and then precipitated as the hydroxide. With incomplete reduction, hexavalent chromium remains in solution in the effluent water. For this reason, periodic checks for chromium in the effluent are necessary. AB-029 Determination of chlorine in water with the 662 Photometer The well-known method for determining free chlorine in water with o-tolidine is described and the absorbance coefficients determined for the 662 Photometer are given.
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