OIL Potentiometric Analysis Collection OIL PAC 6.003 Methods for the titrimetric / potentiometric analysis of petrochemical products Dear User, You have decided to purchase a Metrohm titrator whose collection of methods is specially adapted to your particular requirements. Metrohm always tries to provide its customers with as comprehensive a range of support as is possible in order to facilitate daily analytical work. In this Application binder you will find descriptions of the corresponding analytical methods with comments, explanations and - particularly important - printouts of the instrument parameters and examples of curves. All these methods are stored on the Method memory card.
You only need to insert the card, load the required method into the titrator's working memory and off you go!!! We hope that your work will be both pleasant and successful, Your Metrohm Additional information – These methods have been drawn up taking into account the latest standards. In particular, they make use of the newest methods and the newly developed Metrosensors, which have been specially designed for non- aqueous titrations. – All methods have been designed so that you can adopt them in your oil laboratory as so-called SOPs (Standard Operating Procedures). – Of course, almost all these methods, at least as far as their titration part is concerned, can be further automated.
In the Appendix you will find an example of the complete automation of the titrimetric determination of the base number. For details please contact your local Metrohm supplier, whose address can be found on the Internet under: www.com Distributors – The Method memory card supplied can be used with the 785 and 751 Titrinos (from program version 20). You or your Metrohm supplier can also use the demo version of VESUV 3. The demo version can be converted to a full version by purchasing a «VESUV Hard- ware Dongle».
– The supplied CD ROMs contain, among other things: • The VESUV backup file; this allows you to copy the 25 methods into the 716, 736, 751 and 785 Titrinos. For further information please read the section «Restore methods» in the VESUV Instructions for Use or contact your Metrohm supplier. If the VESUV software is used instead of the printer for receiving the data then the «curve» report must be deleted at the Titrino and the latter set to «mplist» (VESUV can only process measuring point lists). • Acrobat Reader for installation on your PC so that you can read the PDF files.
• Application Bulletins Nos. – The method overview can be removed from the binder and stored together with the OIL PAC card at the corresponding instrument. – We recommend that only those methods that are actually required are loaded into the instrument. Symbols used c(X) Concentration of substance X in mol/L («amount-of-substance concentration») M(X) Molar mass of substance X in g/mol p Pressure in bar or mbar pn Standard pressure (1013.25 mbar) t Temperature in °C T Temperature in K V Volume in L, mL Vn Standard volume (V at 1013.25 mbar and 0 °C) in L (or dm3) or mL w(X) Mass fraction of substance X, e.
w(HCl) = 35% F(X) Volume fraction of substance X, e. F(EtOH) = 40% ?(X) Mass concentration of substance X, e. ?(Pb2+) = 1 g/L List of methods A - Acid and base numbers Method 1 Titer determination for base number Method 2 Base number Method 3 Basic nitrogen Method 4 Titer determination for acid number Method 5 Acid number B - Bromine number and bromine index Method 6 Titer determination Method 7 Blank value of solvent Method 8 Bromine number of cyclohexene Method 9 Bromine index of heptane C - H2S / COS / mercaptans / total sulfur Method 10 Titer determination of AgNO3 Method 11 Sulfur compounds in petroleum products Method 12 Sulfur compounds in gases / absorption solutions Method 13 Total sulfur in petroleum products (Lamp method, ASTM D 1266-98) D - Saponification and hydroxyl numbers Method 14 Saponification number Method 15 Hydroxyl number E - Chloride and organically bound chlorine Method 16 Titer determination of AgNO3 Method 17 Chloride in water and fouled catalysts Method 18 Organically bound chlorine in crude oil F - Absorption solutions for gases Method 19 Alkalinity of amine-containing gas-absorbing solutions (Jefferson method) Method 20 Analysis of used alkaline absorbing and washing solutions G - Metals [Me(II)] in lubricating oils Method 21 Titer determination of EDTA solutions Method 22 Sum of Ba, Ca, Mg, Pb and Zn in unused lubricants H - Further methods Method 23 Ca and Mg in water (water hardness) Method 24 Pb in leaded gasoline Method 25 Icing inhibitors in hydrocarbon fuels Remarks concerning the literature references Metrohm You can obtain the Application Bulletins and Application Notes free of charge from Metrohm Ltd., CH-9101 Herisau (Switzerland) or from your Metrohm supplier. The Metrohm Application Notes can also be viewed in and downloaded from the Internet, «www.
All the additional methods can be obtained against payment at the corresponding addresses: ASTM American Society for Testing and Materials 100 Barr Harbor Dr. West Conshohocken, PA 19428 USA www.org DIN Beuth Verlag GmbH 10772 Berlin Deutschland www.de ISO ISO Central Secretariat 1, Rue de Varembé, P. Box 56 1211 Genève 20 Switzerland www.ch or the member body of you country, which you will find under: www.ch/addresse/membodies.html UOP Universal Oil Products Des Plaines, Illinois (USA) www.com NIST National Institute of Standards and Technology 100 Bureau Drive Stop 3460 Gaithersburg, MD 20899-3460 USA www.gov Index / Key Word List (Method Nr.) A Absorption solution (M 20) J Jefferson Method (M 19) Acid number (M 5) Alkalinity (M 19 / 20) L Lamp Method (M 19) Lead (M 24) B Base number (M 2) Basic nitrogen (M 3) M Mercaptan (M 11 / 12) Blank (M 7, M 2, 3, 5, 8, 9, 14, 18) Mg (M 22 / 23) Bromine Index (M 9) Bromine Number (M 8) N Nitrogen (M 3) C Ca (M 22 / 23) O Organic chlorine (M 18) Calibration factor (M 25) Carbonyl sulfide (M 12) P Pb (M 24) Catalyst (M 17) Caustic solution (M 20) R Refinery caustic solution (M 20) Chloride (M 17) Chlorine (M 18) S Saponification number (M 14) Sea water (M 17) D Diethyl lead (M 24) Sulfur (M 11 / 12 / 13) Diethylene glycol monomethylether (M 25) Drinking water (M 17 / 23) T Tap water (M 17 / 23) Tetraalkyl lead (M 24) E EGME (M 25) Titer determination (M 1 / 4 / 6 / 10 / 16 / 21) Ethyleneglycol monomethylether (M 25) Total acid number – TAN (M 5) Total base number – TBN (M 2) F Formation water (M 17) Total sulfur (M 13) Fouled catalyst (M 17) U Used refinery caustic solution (M 20) H Hardness, water (M 23) Hydrogen sulfide (M 11 / 12) W Washing solution (M 20) Hydroxyl number (M 15) Water hardness (M 23) I Icing Inhibitors (M 25) Method 1 – Titer determination for the base number Recommended accessories • 6.223 Exchange Unit, 20 mL • 6.000 electrolyte diluted 1:1 with ethanol (approx. 2 mol/L LiCl in ethanol) • 6.020 electrode cable General Most standard solutions/titrants are commercially available as ready-to-use solu- tions and have a relatively stable titer.
However, their titer is valid for 20 °C. Please note that non-aqueous solvents have a coefficient of expansion which is four times larger than that of water! This means that, for a temperature difference of 5 °C and a theoretical consumption of 10.00 mL, the actual consumption will be 50 µL higher, i.000 at 20 °C will be 0. Titer determinations and sample analysis should therefore be carried out at the same temperature whenever pos- sible. The following titrants are available from Merck: – No.1 mol/L in anhydrous acetic acid (glacial acetic acid) – No.1 mol/L in isopropanol (IPA) If the titer is to be determined then this is done by comparing it with a so-called primary titrimetric standard.
The content of these hardly changes, they are avail- able with a defined degree of purity, can be dried and are directly traceable to standard reference materials (e. from NIST = National Institute of Standards and Technology, USA). Such recommended primary titrimetric standards or sec- ondary standards are: – Merck No. 104874 Potassium hydrogen phthalate, M = 204.23 g/mol – Merck No.1 Titer determination of c(HClO4) = 0.1 mol/L with KH phthalate Weigh out approx.
200 mg KH phthalate into a beaker to 0. Add 40 mL glacial acetic acid and stir the mixture at room temperature until everything has dissolved (5. After the addition of 40 mL toluene the electrodes are im- mersed and the solution is titrated with HClO4 until after the first endpoint (instru- ment parameters and an example of a curve are given in the appendix).1 mol HClO4 reacts with 0.1 mol KH phthalate 1 mL c(HClO4) = 0.1 mol/L corresponds to 20.423 mg KH phthalate Titer = (C00 / C01) / EP1 EP1 = titrant consumption up to the endpoint, in mL C00 = weight KH phthalate in mg C01 = 20.1 mol/L corresponds to 20.423 mg KH phthalate) Reaction Page 1 Method 1 – Titer determination for the base number 1.2 Titer determination of c(HCl) = 0.1 mol/L with TRIS Approx. 100 mg TRIS is weighed out into a beaker to 0.1 mg exactly and dissolved in approx.
50 mL Isopropanol and 40 mL toluene are added, the electrodes are immersed and the solution is titrated with HCl until after the first endpoint (instrument parameters as for HClO4; an example of a curve is given in the appendix).1 mol HCl reacts with 0.1 mol TRIS Calculation 1 mL c(HCl) = 0.1 mol/L corresponds to 12.114 mg TRIS Titer = C00 / C01 / EP1 EP1 = titrant consumption up to the endpoint, in mL C00 = weight TRIS in mg C01 = 12.1 mol/L corresponds to 12.114 mg TRIS) NH2C(CH2OH)3 + HCl → NH2C(CH2OH)3•HCl Reaction – The titer determination is normally carried out three times and the mean value Remarks is used. – The mean value of the titer is stored as common variable C30 in the Titrino. – If you want to prepare the titrant yourself then proceed as follows: For c(HClO4) = 0.1 mol/L in glacial acetic acid: Approx. 800 mL glacial acetic acid is placed in a 1 liter volumetric flask.
It is treated with 8.68 g/cm3), made up to the mark with glacial acetic acid and mixed.1 mol/L in isopropanol: Approx. 800 mL IPA is placed in a 1 liter volumetric flask. It is treated with 9.16 g/cm3), made up to the mark with IPA and mixed. Page 2 Method 1 – Titer determination for the base number Method parameters & calculation Titration curves Method 1.1 'pa 785 DMP Titrino 02287 785.0010 date 2000-11-13 time 11:31 0 DET U M1.1 parameters >titration parameters meas.
ml/min signal drift 30 mV/min equilibr.time 26 s start V: OFF pause 10 s meas.0 °C >stop conditions stop V: abs. stop V 20 ml stop U OFF mV stop EP 9 filling rate max. ml/min Method 1.2 >statistics status: ON mean n= 3 res.tab: original >evaluation EPC 5 EP recognition: all fix EP1 at U OFF mV pK/HNP: OFF >preselections req.ident: id1 req.smpl size: all limit smpl size: OFF activate pulse: OFF ------------ 'de 785 DMP Titrino 02287 785.0010 date 2000-11-13 time 11:31 DET U M1.1 def >formula Titer=C00/C01/EP1 RS1 text Titer RS1 decimal places 4 RS1 unit: RS1 limit control: OFF >silo calculations match id: OFF >common variables C30=MN1 >report report COM1:full;curve; >mean MN1=RS1 >temporary variables ------------ 'cf 785 DMP Titrino 02287 785.0010 date 2000-11-13 time 11:31 DET U M1.423 ------------ Page 3 Method 2 – Determination of the base number Recommended accessories • 6.223 Exchange Unit, 20 mL • 6.000 electrolyte diluted 1:1 with ethanol (approx. 2 mol/L LiCl in ethanol) • 6.020 electrode cable General Components in oil products that exhibit a basic reaction are determined as a cu- mulative total under the base number.