Uygulamalar
- AN-H-143Sulfuric acid and tartaric acid in tartaric sulfuric anodizing bath – Rapid, sequential determination using a thermometric sensor (thermometric titration)
Tartaric Sulfuric Anodizing (TSA) is an established technique for corrosion protection in the aerospace industry. It is an alternative to the environmentally harmful chromic anodizing process. As such, a method to monitor the levels of sulfuric acid and tartaric acid in TSA plating baths is required. Potentiometric titration methods have been developed, and are widely used across the industry. Their disadvantage is that two titrations with different electrodes and solvents are required.In this Application Note, an alternative method is presented, where the concentration of both acids is determined in sequence using a thermometric sensor. Compared to potentiometric titration, thermometric titration is faster and more convenient (no sensor maintenance required). On a fully automated system, the determination of both parameters takes about 7 minutes.
- AB-343Automated determination of sodium in milk with thermometric titration
This bulletin discusses automated determination of sodium in milk products available to the public using a 859 Titrotherm and a 814 USB Sample Processor. The sodium content of milk can be rapidly and easily titrated thermometrically with a standard solution of Al3+ as titrant. Thermometric titrations are conducted under conditions of constant titrant addition rate. The molarity of the titrant is computed automatically in tiamoTM (software) with the SLO command. Results are reported as mg Na/100 mL. In addition to this application bulletin, you can find more information on thermometric sodium determination in foods in our application video available on YouTube:https://youtu.be/lnCp9jBxoEs
- 8.000.6066Determination of the total acid number (TAN) using thermometric titration
The thermometric titration method presented here permits a simple and direct determination of the total acid number (TAN) in petroleum products. It is an invaluable alternative to current manual and potentiometric methods. Thermometric titration uses a maintenance-free temperature sensor that does not require rehydration and is free of fouling and matrix effects. The procedure requires minimal sample preparation. Results agree closely with those from the potentiometric titrimetric procedure according to ASTM D664, but the thermometric titration method is far superior in terms of reproducibility and speed of analysis, with determinations being complete in approximately one minute.
- AB-313Analysis of Bayer process liquors using thermometric titration
The determination of the total causticizer, sodium carbonate and aluminum oxide contents in (Bayer) process liquors can be accomplished with high precision and speed by using the 859 Titrotherm in a thermometric acid-base titration. A complete titration takes approximately 5 minutes.The procedure is an automated adaptation of the traditional Watts-Utley method, and is similar to the VanDalen-Ward thermometric titration method, but with the added advantage that the analysis can also be performed for the carbonate content of the liquor.
- AB-427Acid number in petroleum products with thermometric titration
This Application Bulletin describes the determination of the total acid number in various oil samples by catalytic thermometric titration as per ASTM D8045.
- AB-298Sodium determination in various foods with thermometric titration
In an acidic solution (containing NH4F * HF, Al(NO3)3 / KNO3) sodium forms NaK2AlF6 which precipitates in an exothermic solution, enabling analysis by thermometric titration. Several foods were analyzed, namely bouillon, gravy, tomato ketchup, corn chips, pretzel sticks as well as crackers. The reproducibility of the results was good. After weighing in and adding solutions, samples were crushed with a polytron to ensure homogeneity in the measuring solution. Relative standard deviations were between 0.08% and 3.75%. In addition to this application bulletin, you can find more information on thermometric sodium determination in foods in our application video available on YouTube:https://youtu.be/lnCp9jBxoEs
- AN-H-127Thermometric analysis of aluminum by back-titration
This Application Note describes the determination of aluminum in samples containing silicon dioxide using thermometric titration and EDTA as the titrant. Excess EDTA is titrated with a Cu2+ solution of known concentration. The initial, uncomplexed Cu2+ ions react immediately with the H2O2 present in the solution, leading to a recognizable sudden increase in temperature.
- AN-H-132Thermometric endpoint titration of hydrogen peroxide with iodometry
Hydrogen peroxide solutions can be determined through thermometric endpoint titration (TET) using iodometry. Iodide is oxidized to become iodine, which is then titrated with a standard thiosulfate solution in an exothermic reaction.
- AN-H-090Nickel in electroless nickel solutions by thermometric EDTA titration
Automated thermometric titration of the nickel content of electroless nickel plating solutions. The determination is suitable for fully automated titration employing a 814 Sample Processor.
- AN-H-129Determination of weak bases in nonaqueous media through catalyzed thermometric endpoint titration (CETT)
Weak, organic bases that are soluble in nonaqueous solvents (including nonpolar solvents) are determined in glacial acetic acid using titration with strong acids, e. g., anhydrous perchloric acid or trifluoromethanesulfonic acid. The endpoint of such titrations can be determined thermometrically, insofar as a suitable thermometric endpoint indicator exists. The exceptional suitability of isobutyl vinyl ether (IBVE) as indicator has been demonstrated.
- AB-066Potentiometric and thermometric determination of boric acid
Boric acid is used in many primary circuits of nuclear power plants, in nickel plating baths, and in the production of optical glasses. Furthermore, boron compounds are found in washing powders and fertilizers. This bulletin describes the potentiometric and thermometric determination of boric acid. The determination also covers further boron compounds, when acidic digestion is applied.
- AN-H-131Determination of titer and blank value for thermometric titrations using tiamo™
This Application Note describes in detail how to determine the blank value and the titer for thermometric titrations using tiamo™.
- AN-PAN-1037Online measurement of the acid number (AN) in oils with thermometric titration (ASTM D8045)
Online acid number analysis in various oil products is possible with thermometric catalytic titration according to ASTM D8045 using the 2060 TI Ex Proof Process Analyzer.
- AB-308Determination of sulfate in phosphoric acid (liquid fertilizer samples) with thermometric titration
Sulfate can be rapidly and easily titrated thermometrically using a standard solution of Ba2+ as titrant. In industry, the widespread procedure is applied to the determination of sulfate in wet-process phosphoric acid.
- AB-307Determination of sulfate in granular phosphate fertilizers with thermometric titration
Sulfate can be rapidly and easily titrated thermometrically using a standard solution of Ba2+ as titrant. In industry, the widespread procedure is applied to the determination of sulfate in wet-process phosphoric acid. This bulletin deals with the determination of sulfate in granular fertilizers such as MAP (monoammonium phosphate), DAP (diammonium phosphate) and TSP (triple superphosphate). Results are reported as percentage of elemental sulfur, %S.
- AN-PAN-1034Analysis of Bayer aluminate liquors using thermometric titration
The Bayer Process is the method used to refine alumina from bauxite ore, as smelting aluminum directly from alumina is much more cost- and energy-effective. In this process, "aluminate liquors" are created by digesting the crushed bauxite with CaO and NaOH at high temperatures. Additionally, the CaO causticizes carbonate which forms in the alkaline solution from organic degradation and CO2 absorption from the atmosphere. Contaminations are removed at various steps in the process, and the liquor is filtered from the alumina crystals before it is recycled back to the digestion step. Before the spent liquor can be reused, a determination of the concentrations of the total hydroxyl (“caustic”), carbonate, and alumina values is required. These parameters can be determined quickly via thermometric titration with the 2035 Process Analyzer.
- AB-342Automated determination of calcium and magnesium in milk with thermometric titration
This bulletin deals with the automated determination of calcium and magnesium in commercially available finished milk products using a 859 Titrotherm and a 814 USB Sample Processor. Calcium and magnesium in milk can be rapidly and easily titrated thermometrically using a standard solution of Na4EDTA as titrant.Thermometric titrations are conducted under conditions of constant titrant addition rate. The molarity of the titrant is computed automatically in tiamo (software) using the SLO command. Results are reported as mg Ca and Mg/100 mL.
- AB-314Determination of total phosphate in phosphoric acid and phosphate fertilizers with thermometric titration
Phosphate can be rapidly and easily titrated thermometrically using a standard solution of Mg2+ as titrant. The phosphate-containing solution is basified and buffered with NH3/NH4Cl solution before titration. The formation of insoluble MgNH4PO4 is exothermic. The method is a titrimetric adaptation of a classical gravimetric procedure. This bulletin deals with the determination of phosphate in phosphoric acid and granular fertilizers such as MAP (monoammonium phosphate), DAP (diammonium phosphate) and TSP (triple superphosphate). Results are reported as percentage of P and P2O5.
- AN-H-035Phosphate in fertilizers – Rapid and reliable determination by thermometric titration
Phosphorus is a primary macronutrient for plants and is a constituent of DNA and adenosine triphosphate (ATP), which is involved in many biological processes requiring energy. In fertilizers, phosphorus is present in the form of phosphate, as the most accessible form of phosphorus for plants is dihydrogen phosphate. Knowledge of the phosphorus content helps to select the right fertilizer for the plants.Traditionally, phosphate is determined gravimetrically (a time consuming procedure) or spectrophotometrically (expensive instrumentation). In this Application Note, an alternative method is presented, where phosphate is determined by a precipitation titration with magnesium. Various solid and liquid NPK fertilizers with phosphorus contents between 6.5 and 17% were analyzed. The analysis by thermometric titration requires no sample preparation in case of liquid NPK fertilizers and only minimal sample preparation in case of solid NPK fertilizers. One determination takes about 5 minutes.
- WP-060Multiparameter analysis in fertilizers: Fast and easy via thermometric titration
Agriculture at significant scale without fertilizers is no longer possible in the modern world. To grow a sufficient amount of produce for nearly 8 billion people as well as for domesticated animals and industrial uses, fertilizers of different nutrient compositions are available to cater to the unique needs of various soil types. Information on the fertilizer’s composition (e.g., total nitrogen, phosphorus, and potassium) is available to help select the ideal fertilizer for a specific soil. Conventionally these constituents are determined either gravimetrically (e.g., phosphorus, potassium, or sulfate) or with ICP-OES (e.g., phosphorus or potassium). These methods either have the disadvantages of long analysis times combined with laborious sample preparation (gravimetry), or require expensive instrumentation with high running costs (ICP-OES). This White Paper elaborates how thermometric titration is a fast and inexpensive alternative method to provide information on the content of various nutrients in different fertilizers.
- AN-H-145Sulfate in fertilizers – Rapid and reliable determination by thermometric titration
Sulfur is a secondary macronutrient for plants and is essential for chloroplast growth and function. In fertilizers, sulfur is usually provided in the form of sulfate. Traditionally the sulfate content is determined gravimetrically by precipitation with barium. The drawback of this method is that it requires numerous time consuming and laborious analysis steps.In this Application Note, an alternative method is presented, where sulfate is determined by a precipitation titration with barium chloride. Various solid and liquid NPK fertilizers with sulfur contents between 1 and 8% were analyzed. The analysis of sulfate in fertilizers by thermometric titration requires no sample preparation at all for liquid NPK fertilizers, and only minimal sample preparation for solid NPK fertilizers. One determination takes about 3 minutes only. To increase the sensitivity of the method, the samples are spiked with a standard sulfuric acid solution, which is then considered when calculating the result.
- AB-344Automated analysis of etch acid mixtures for silicon substrates with thermometric titration
This bulletin deals with the automated determination of mixtures of HNO3, HF and H2SiF6 in the range of approximately 200-600 g/L HNO3, 50-160 g/L HF, and 0-185 g/L H2SiF6 using thermometric titration.Etch acid mixtures containing HNO3, HF and H2SiF6 from the etching of silicon substrates can be analyzed in a sequence of two determinations using the 859 Titrotherm. The first determination involves a direct titration with standard c(NaOH) = 2 mol/L, followed by a back titration with c(HCl) = 2 mol/L. This determination yields the H2SiF6 content plus a value for the combined (HNO3+HF) contents. The second determination consists of a titration with c(Al3+) = 0.5 mol/L to determine the HF content. For freshly made up mixtures of HNO3 and HF containing no H2SiF6, a linked two-titration sequence is employed. Results from the two determinations are used by tiamoTM to yield individual results for HNO3, HF and H2SiF6.
- 8.000.6080Thermometric titration – the missing piece of the titration puzzle
Thermometric titration can solve application problems that potentiometry cannot solve at all, or at least not satisfactorily.
- AN-H-135Determination of hydrochloric acid and phosphoric acid in etching baths using thermometric titration
Thermometric titration is used for the determination of hydrochloric acid and phosphoric acid in acid mixtures. Two endpoints appear on the titration curve that are used for the determination of the two acids.
- AN-H-138Determination of nitric acid and hydrofluoric acid in etching baths using thermometric titration
Thermometric titration is used to determine hydrofluoric acid and nitric acid in etching baths containing ethanol and acetonitrile. Two endpoints appear on the titration curve that are used individually for the quantification of the respective acid.
- AN-H-134Determination of sulfuric acid and phosphoric acid in etching baths using thermometric titration
Thermometric titration can be used for the ready determination of sulfuric acid and phosphoric acid in acid mixtures. An endpoint for each acid appears on the titration curve that can be used to quantify the respective acid.
- AN-H-137Determination of hydrochloric acid and hydrofluoric acid in etching baths using thermometric titration
Thermometric titration is used to determine hydrochloric acid and hydrofluoric acid (hydrogen fluoride) in etching baths containing ethanol and acetonitrile. Two endpoints appear on the titration curve that are used individually for the quantification of the respective acid.
- AN-H-136Determination of hydrochloric acid and nitric acid in etching baths using thermometric titration
Thermometric titration is used for the determination of hydrochloric acid and nitric acid in acid baths. The entire acid content is titrated with caustic soda in the initial titration; the hydrochloric acid content is then determined in a second titration using silver nitrate solution.
- WP-012Corrosion control: Thermometric TAN analysis in oil & refinery distillation fractions
Many refiners look at discounted opportunity crudes as a means to improve their margin spread. The varieties of these cheap crude oils on the market are growing in number, but they have hidden risks for the purchaser caused by factors such as high naphthenic acid and sulfur content. Sulfur compounds and naphthenic acids are among the substances that contribute to the corrosive nature of crude oils and petroleum products. This is why the risk of corrosion is increased when processing crude oils with high naphthenic acid and sulfur content. The refiner must balance the cost benefit versus the risk and the cost of corrosion control when processing these crudes. A reliable acid number determination is a crucial part of corrosion control. Guest authors Bert Thakkar, Bryce McGarvey, and Colette McGarvey of Imperial Oil and Larry Tucker and Lori Carey of Metrohm USA were involved in the development of the new ASTM Method D8045 for acid number determination. Here, they report on the method and how it came to be.
- AB-316Determination of phosphoric acid in liquid fertilizer with thermometric titration
The phosphoric acid content can be easily titrated with a standardized solution of 2 mol/L NaOH. The interfering calcium content in phosphoric fertilizer can be eliminated by adding a saturated oxalate solution.
- AB-315Determination of free fatty acids (FFA) in edible oils with thermometric titration
In titration, the titrant reacts with the analyte either exothermically (gives off heat) or endothermically (absorbs heat). The Thermoprobe measures the temperature change during titration. When all of the analyte has reacted with the titrant, the temperature of the solution will change, and the endpoint of the titration is indicated by an inflection in the temperature curve. Catalytically enhanced titrations using paraformaldehyde as catalyst are based on the endothermic hydrolysis of the paraformaldehyde in the presence of excess hydroxide ions. Edible oils are dissolved in a mixture of toluene and 2-propanol (1:1) and titrated with standardized TBAH (0.01 mol/L) in 2-propanol to a catalytically enhanced endpoint.
- AN-H-147Potassium in fertilizers – Rapid and reliable determination by thermometric titration
Potassium is a primary macronutrient for plants, as it plays an important role in water regulation as well as plant growth. In NPK fertilizers, potassium is present besides nitrogen and phosphorus, which are the other two primary macronutrients. Knowing the quality and content of a NPK fertilizer allows an optimal fertilizer management for a planned culture, saving costs and increasing profitability.Traditionally potassium is determined gravimetrically or by flame photometry. In this Application Note, an alternative method is presented, where potassium is determined a precipitation titration. Various solid and liquid NPK fertilizers with potassium contents between 10 and 27% were analyzed. After the removal of any present ammonia, the potassium can be determined reliably in about 5 minutes.
- AN-H-139Determination of nitric acid, hydrofluoric acid and hexafluorosilic acid in simulated etching baths using thermometric titration
Following the addition of caustic soda, hexafluorosilic acid can be determined through back titration of excess hydroxide with hydrochloric acid. Hydrofluoric acid (hydrogen fluoride) is determined by precipitation with aluminum in the presence of sodium and potassium ions. Nitric acid is determined by subtracting the equivalence concentrations of hexafluorosilic acid and hydrofluoric acid from the total acid concentration.
- AN-H-122Determination of sodium in canned fish products
This Application Note describes the determination of total sodium content in canned fish products using thermometric titration. In addition to this application note, you can find more information on thermometric sodium determination in foods in our application video available on YouTube:https://youtu.be/lnCp9jBxoEs
- AN-H-133Automatic sodium determination in cheese
Sodium can be determined thermometrically in cheese without sample preparation and addition of additives. A homogenizer is responsible for distribution and stirring. In addition to this application note, you can find more information on thermometric sodium determination in foods in our application video available on YouTube:https://youtu.be/lnCp9jBxoEs
- AN-H-144Ferrous iron in iron sucrose injection
Iron sucrose injections are used during the treatment of iron deficiency anemia. They contain a mixture of ferric iron (Fe3+) and ferrous iron (Fe2+). Ferrous iron content may be determined by subtracting the ferric iron content from the total determined iron content. Yet, this increases the measurement error due to error propagation. Alternative determination of iron(II) with cerium(IV) by potentiometric titration may be hampered, as the equivalence point cannot be determined unequivocally. Determination by thermometric titration is a more robust and therefore more reliable alternative, as this method is unaffected by the sample matrix. Here, the endpoint of the titration is indicated by a fast responding thermometric sensor. Endpoint detection is further improved by spiking the sample with 0.2% ammonium iron(II) sulfate (FAS), increasing the reliability of the determination. Compared to potentiometric titration, thermometric titration is faster and more convenient as no sensor maintenance is required. One determination takes about 2–3 minutes.
- AN-T-095Automated mixing of a suspension and a solvent using a 50 mL dosing unit
Automated mixing of a suspension and a solvent in a 50 mL dosing unit can be used to add a well-defined amount of a suspension-solvent mixture to a sample solution without clogging the dosing unit and tubing by the undiluted suspension.The method is explained by means of the TAN determination of a petroleum sample using thermometric titration. For a better endpoint recognition, small amounts of a paraformaldehyde-solvent suspension are added (catalyzed endpoint thermometric titration).
- AN-H-141Acid number in crude oil and gas oil according to ASTM D8045
Thermometric titration can determine the total acid number (TAN) of various crude oil products according to ASTM D8045 without requiring any sensor maintenance.
- AN-H-075Standardization of tetrasodium EDTA solutions
Standardization of ~1mol/L tetrasodium EDTA solutions for thermometric complexometric analysis.
- AN-H-048Standardization of disodium dimethylglyoximate for the determination of nickel
Standardization of disodium dimethylglyoximate by thermometric titration with standard Ni(II) solution.
- AN-H-066Carbonate and bicarbonate in solution
Determination of bicarbonate and carbonate in a mixture by sequential thermometric titrations.
- AN-H-031Determination of low levels of sulfate by barium chromate displacement
Determination of low levels of sulfate (to approximately 20mg/L SO42-) by thermometric titration.
- AN-H-096Determination of total base number of lubricating oils
Dissolution of oil in toluene, and titration with standard 0.1 mol/L trifluoromethanesulfonic acid in acetic acid using isobutyl vinyl ether as a thermometric endpoint indicator.
- AN-H-060Standardization of 0.1 mol/L perchloric acid in glacial acetic acid
Standardization of 0.1mol/L perchloric acid in glacial acetic acid by catalyzed endpoint thermometric titration.
- AN-H-033Determination of low levels of chloride in water
Determination of low levels of chloride (to approximately 5 mg/L Cl-) by thermometric titration.
- AN-H-098Determination of hydrofluoric acid in silicon etch solutions
This Application Note describes the determination of fluoride in silicon etch solutions with thermometric titration.
- AN-H-032Standardization of ammonium ferrous sulfate solution
Standardization of 0.1 mol/L ammonium ferrous sulfate solution for use in thermometric titration of Cr(VI) solutions.
- AN-H-004Determination of fluoride by boric acid titration
This Application Note explains how fluoride determination in acid etching baths can be performed with thermometric titration.
- AN-H-082Determination of surface acidity in Zeolites and other materials with a high specific surface area
This Application Note outlines the determination of total acidic active surface sites in zeolites with thermometric titration.
- AN-H-083Determination of surface basicity in zeolites and other materials with a high specific surface area
This Application Note shows that the parameter of surface basicity of zeolites can be measured by thermometric titration.
- AN-H-042Standardization of thiosulfate titrant for copper determinations
This Application Note discusses the standardization of thiosulfate titrant for use in the determination of copper with thermometric titration.
- AN-H-140Titration of phosphoric, nitric, and acetic acid mixtures
Nitric acid, phosphoric acid, and acetic acid are easily determined in etching baths using thermometric titration (TET). Compared to potentiometric titration, TET is faster and more convenient. Analysis is complete in less than two minutes.
- AN-H-011Determination of the total solids content of drilling fluids
Thermometric titration is presented as a simple, fast, and reliable method to determine calcium content in various drilling fluids.
- AN-H-010Determination of calcium in drilling fluids
Thermometric titration quickly and accurately assesses the total solids content of fluids employed in drilling oil and gas wells within minutes.
- AN-H-128Determination of ferrous ion in acidic solutions with permanganate as titrant
This Application Note looks at the determination of ferrous ion in acidic solutions through redox titration with potassium permanganate as titrant and thermometric titration.
- AN-H-030Determination of chlorite by direct titration with thiosulfate
Determination of chlorite by direct thermometric titration with standard sodium thiosulfate solution. The procedurewas applied originally to the determination of chlorite in hide treatment solutions.
- AN-H-123Determination of sodium in instant noodles
This Application Note describes the determination of the total sodium content in instant noodles which are also called «two minute noodles» in some countries. These products contain considerable amounts of sodium (at least 50% of the recommended daily dosage), which means that precise analysis of the sodium content is required. Argentometric titration of the chloride content (assuming that the sodium content in the noodles originates exclusively from the sodium chloride that is added to them) is unsuitable for precise analysis, as the nutrient contents listed on the product packaging document the presence of additional sodium salts other than sodium chloride. Thermometric titration enables fast and direct determination of sodium. In addition to this application note, you can find more information on thermometric sodium determination in foods in our application video available on YouTube:https://youtu.be/lnCp9jBxoEs
- AN-H-095Determination of urea by non-aqueous titration
Dissolution of urea in glacial acetic acid, and titration with standard 0.1 mol/L trifluoromethanesulfonic acid in acetic acid using isobutyl vinyl ether as a thermometric endpoint indicator.
- AN-H-130Determination of nitrite using sulfamic acid
This Application Note describes the determination of nitrite using thermometric endpoint titration with sulfamic acid. The nitrite content of a solution can be analyzed down to 0.2 mmol/L.
- AB-140Titrimetric sulfate determination
This Bulletin describes three potentiometric, one photometric, one thermometric and one conductometric titration method for sulfate determination. The question of which indication method is the most suitable depends primarily on the sample matrix.Method 1: Precipitation as barium sulfate and back titration of the Ba2+ surplus with EGTA. Use of the ion-selective calcium electrode as indicator electrode.Method 2: As with Method 1, although with the electrode combination tungsten/platinum.Method 3: Precipitation titration in semi-aqueous solution with lead nitrate in accordance with the European Pharmacopoeia using the ion-selective lead electrode as indicator electrode.Method 4: Photometric titration with lead nitrate, dithizone indicator and the Optrode 610 nm, particularly suitable for low concentrations (up to 5 mg SO42- in the sample solution).Method 5: Thermometric precipitation titration with Ba2+ in aqueous solution, particularly suitable for fertilizers.Method 6: Conductometric titration with barium acetate in accordance with DIN 53127
- AN-H-126Determination of silver and nitric acid in silver electrolyte bath
Silver and nitric acid are determined in silver electrolyte solutions by means of thermometric titration. The method provides accurate results in a short time and is ideally suited for routine process control.
- AN-H-070Determination of ferric and cupric Ions in copper refining solutions
Determination of Fe3+ and Cu2+ in copper refining solutions by thermometric titration. It was found that the conventional approach of masking Fe3+ to permit the iodometric determination of Cu2+ is not possible in some copper refining solutions.
- AN-H-097Determination of calcium and magnesium in harvested salt
A measured amount of salt is titrated directly with a solution of 1 mol/L tetrasodium EDTA to thermometrically determined endpoints for Ca and Mg. Acetylacetone is added to alter the Ca and Mg EDTA stability constants for better endpoint sharpness.
- AN-H-121Determination of ferrous ion in acidic solutions with ceric solution
This Application Note looks at the determination of ferrous ion in acidic solutions from approximately 0.25 g/L by thermometric titration with ceric titrant. The exothermic oxidation reaction shows a sharp endpoint that is detected using the Thermoprobe as a sensitive temperature sensor.
- AN-H-110Determination of sulfate in drinking water by barium chromate displacement
Sulfate is precipitated by reaction with an acidified barium chromate solution. The excess barium chromate is precipitated by basification with ammonia solution. Residual soluble chromate equivalent to the sulfate content of the sample is titrated with a solution of standard ferrous ion to a thermometrically determined endpoint.
- AN-H-119Determination of ferric ion in acidic solutions
This Application Note deals with the determination of ferric ion in acidic and copper-free solutions using thermometric titration. The ferric ion is reduced by iodide. The released iodine reacts exothermically when titrated with thiosulfate solution. The endpoint is determined through temperature plotting by the temperature sensor Thermoprobe.
- AN-H-111Determination of sulfate in harvested salt
Sulfate is precipitated as barium sulfate by reaction with an acidified barium chromate solution. The excess barium chromate is precipitated by basification with ammonia solution. Residual soluble chromate, equivalent to the sulfate content of the sample, is titrated with a solution of standard ferrous ion to a thermometrically determined endpoint.
- AN-H-024Determination of tar acids (phenolics) in tar products
Determination of tar acids in coal tar products. This procedure may also be applied to the determination of a range of weakly acidic organic compounds such as carboxylic acids, hydroxy acids, phenols, phenolic acids, keto-enols, imides, and aromatic nitro compounds.11 Vaughan, G. A. Thermometric and Enthalpimetric Titrimetry. Van Nostrand Reinhold Co. Ltd (1973)
- AN-H-118Determination of hydrochloric acid in acidic solutions containing iron and aluminum
The presence of the hydrated ion [Fe(H2O)6]3+ can interfere with the determination of «free acid» due to the low pKa value (~2.2) of this ion. Ions of metals such as Fe, Cu, and Al can be masked effectively with fluoride, and permit the determination of the acid content by thermometric alkalimetric titration with good accuracy and precision.
- AN-H-115Determination of hydrofluoric acid, ammonium fluoride, and maleic acid in acid cleaning solutions
A direct thermometric titration (TET) with 2 mol/L NaOH is used to determine the HF, NH4F, and maleic acid (C4H4O4) contents of acid cleaning solutions. Three endpoints (EPs) are obtained, which may be assigned as follows:EP1: C4H4O4 (pKa1 = 1.9), HF (pKa = 3.17)EP2: C4H4O4 (pKa2 = 6.07)EP2: NH4F (pKa = 8.2)The HF content is determined by subtracting the difference (EP2-EP1) from EP1.
- AN-H-146Ammonium and urea nitrogen in NPK fertilizers
Fertilizers are applied in the agricultural sector to provide more essential nutrients to growing plants. The so-called «NPK» fertilizers provide such nutrients to plants with its three main components (N – nitrogen, P – phosphorous, K – potassium). In fertilizers, nitrogen is mainly provided in three forms: as ammonium nitrate (NH4NO3), ammonia (NH3), and urea (H2NCONH2). Determination of the individual nitrogen-contributing components is often laborious work. Thermometric titration offers the possibility to rapidly determine the amount of ammoniacal nitrogen and urea nitrogen in a single titration using sodium hypochlorite as titrant.
- AN-H-103Determination of Calcium and Magnesium in Milk
A measured amount of milk is treated with trichloroacetic acid to coagulate milk solids and liberate calcium and magnesium as dissociated ion. The coagulated milk is filtered or centrifuged, and an aliquot of the clear serum is titrated with a standard solution of 1 mol/L tetra-sodium EDTA to thermometrically determined endpoints for Ca and Mg. Acetylacetone is added to alter the Ca- and Mg- EDTA stability constants for better endpoint sharpness.
- AN-H-088Automated determination of total acid number (TAN) in oils
Automated determination of total acid number (TAN) in new and used lubricating oils and crude oils using the 814 USB Sample Processor. Dissolve oil sample in mixture of toluene and 2-propanol, add paraformaldehyde and titrate with 0.1 mol/L or 0.01 mol/L KOH in propan-2-ol. The endpoint is indicated by an endothermic response caused by the base-catalyzed depolymerization of paraformaldehyde.Reference: 1. M. J. D. Carneiro, M. A. Feres Júnior, and O. E. S. Godinho. Determination of the acidity of oils using paraformaldehyde as a thermometric end-point indicator. J. Braz. Chem. Soc. 13 (5) 692-694 (2002)
- AN-H-086Determination of sodium in potato chips
Titration of an unfiltered suspension of the sample with a standardized solution of aluminum containing a stoichiometric excess of potassium ions in the presence of ammonium hydrogen difluoride at ~ pH 3 to give an exothermic reaction, forming insoluble NaK2AlF6. The titrant is standardized against a solution prepared from anhydrous sodium sulfate or sodium carbonate. In addition to this application note, you can find more information on thermometric sodium determination in foods in our application video available on YouTube: https://youtu.be/lnCp9jBxoEs
- AN-H-148Potassium in potash
Potash is commonly mined from ore, deposited after ancient inland oceans evaporated. The potassium salt is then purified in evaporation ponds. At the end of this process, the potash is typically obtained as potassium chloride. Potash is mainly used as fertilizer, providing potassium—an essential nutrient—to plants. Additionally, it is used in the chemical industry and to produce medicine. Potassium content in potash is typically determined by flame photometry (F-AES) or ICP-OES. However, these techniques have high investment and running costs. By applying the historically used gravimetric precipitation reaction as a thermometric titration, it becomes possible to rapidly and inexpensively determine the potassium content in potash within minutes.
- AN-H-124Determination of sodium content in the manufacturing of margarine
This Application Note describes the determination of the total concentration of sodium in precursor solutions used in the manufacturing of margarine. The solutions of the precursors are mixed with edible fats and oils to make margarine. Traces of sodium chloride and other sodium and potassium salts may be added to the margarine during this process, usually in the form of emulsifiers, stabilizers, antioxidants, vitamins, coloring agents or flavor enhancers. The analysis of the total sodium content in the precursor solutions is more efficient and cost-effective for the manufacturers than later total sodium content analyses in the final product.As a rule, argentometric titration of chloride is used for indirect determination of the sodium content of foodstuffs. The assumption behind this approach is that the chloride ions are present in a molar ratio of 1:1 with the sodium ions. This is however not the case when – as is usually the case with foodstuffs containing sodium – additional compounds containing sodium are also present in the margarine. The use of potassium chloride as a partial replacement for sodium chloride in some formulations is an additional source of error.The direct titration of sodium by means of thermometric endpoint titration (TET) eliminates these problems. TET is a direct determination method that not only takes into account the entire sodium content present in the solution but is also not hampered by the presence of potassium ions. In addition to this application note, you can find more information on thermometric sodium determination in foods in our application video available on YouTube:https://youtu.be/lnCp9jBxoEs
- AN-H-142Determination of metal-organic compounds
Metal-organic compounds are commonly used in organic chemistry, for example as Grignard reagents or as strong bases (e.g., butyl lithium compounds). The knowledge of the exact content of reactive species allows to better plan the required amounts for reactions preventing the waste of material or too low yields.This Application Note describes the analysis of metal organics by thermometric titration using 2-butanol as titrant. Due to the strongly exothermic nature of the reaction between 2-butanol with metal-organic compounds, a fast and quantitative analysis of these substances is possible.
- AB-087Analysis of dairy products
This Bulletin describes potentiometric titration methods for the determination of the acidity in milk and yoghurt according to DIN 10316, ISO/TS 11869, IDF/RM 150, ISO 6091 and IDF 86, the chloride content in milk, butter and cheese according to EN ISO 5943, IDF 88, ISO 15648, IDF 179, ISO 21422, and IDF 242. Additionally the determination of the sodium content in milk using the thermometric titration is described. The determination of the oxidation stability of butter in accordance to AOCS Cd 12b-92, ISO 6886 and GB/T 21121 as well as the determination of lactose in lactose free milk by ion chromatography is also described.For the determination of the pH value in dairy products see Application Bulletin AB-086 and for the determination of calcium and magnesium see Application Bulletin AB-235.
- AN-H-052Determination of nickel in electroless plating solutions
Thermometric titration of nickel in electroless plating solution with disodium dimethylglyoximate.
- AN-H-044Standardization of EDTA titrant by copper
Thermometric complexometric titration of metals is often performed with tetrasodium EDTA. This Application Note explains the standardization of tetrasodium EDTA titrant with copper.
- AB-404Total acid number titration of petroleum products
The determination of the acid number plays a significant role in the analysis of petroleum products. This is manifested in the numerous standard procedures in use over the world (internal specifications of multinational companies, national and international specifications of ASTM, DIN, IP, ISO, etc.). These procedures differ mainly in the composition of the used solvents and titrants.This bulletin describes the determination of the acid number in petroleum products by applying different types of titration.The potentiometric determination is described according to ASTM D664, the photometric according to ASTM D974 and the thermometric titration according to ASTM D8045.
- AN-NIR-091Quality Control of Mixed Acetic, Hydrofluoric, and Nitric Acids
This application note discusses an alternative near-infrared (NIR) spectroscopy method that can reliably determine all parameters within a minute, even in complex acid mixtures.
- AN-NIR-090Quality Control of Mixed Phosphoric, Sulfuric, Nitric, and Hydrofluoric Acids
Fast and reliable detection of phosphoric, sulfuric, nitric, and hydrofluoric acids with near-infrared spectroscopy in under one minute.
- AN-H-073Determination of total acid number (TAN) in biodiesel
Determination of Total Acid Number (TAN) values in biodiesel to <0.05 mg KOH/g sample.
- AN-PAN-1004ABC Titration: Analysis of alkali, carbonate, hydroxide, and sulfide in pulping liquors
The Kraft process is the dominant pulping process in the pulp and paper industry with the highest chemical recovery efficiency. In order to run each part of the papermaking process optimally, constant quality checks and analyses should be performed. This Process Application Note illustrates the straightforward online analysis of alkali (active, effective, total titratable alkali (TTA)), carbonate, hydroxide, sulfide and the causticizing degree (CE%) in pulping liquors using a 2060 Process Analyzer from Metrohm Process Analytics.
- AN-H-045Standardization of EDTA titrant by magnesium
This Application Note explains how to use magnesium to standardize tetrasodium EDTA titrant.
- AN-H-064Total base number (TBN) in used motor oils
The determination of the total base number (TBN) in motor oils is accomplished by means of titration with a standard solution made up of trifluoromethanesulfonic acid in glacial acetic acid and isobutyl vinyl ether as reagent for improved end point identification.
- AB-405Total base number titration of petroleum products
This Application Bulletin shows the determination of the total base number in petroleum products by applying different titration types according to various standards.
- AN-PAN-1001Online analysis of hydrogen sulfide and ammonia in sour water stripper
This Process Application Note details the simultaneous online analysis of H2S and NH3 in sour water which was previously treated in the sour water stripper (SWS). The method includes automatic cleaning and calibration. Fast and accurate results are continuously supplied for process control.
- AN-RS-049Determining phosphate concentration with Raman spectroscopy
Raman spectroscopy with PLS modeling enables rapid, accurate, nondestructive quantification of the total phosphate content in solution with minimal sample preparation.
- AN-PAN-1026Mercaptans and hydrogen sulfide in raw oil in accordance with ASTM D3227 and UOP163
Online mercaptan and H₂S monitoring with the 2060 TI Ex Proof Analyzer certified for Zone-1 and Zone-2 areas.
- AN-PAN-1006Online analysis of zinc, sulfuric acid, and iron during zinc refining
This Process Application Note is dedicated to the online analysis of zinc, iron and sulfuric acid in several stages of the zinc production process. Additionally, traces of germanium, antimony, as well as several transition metals (e.g., Ni, Co, Cu, Cd) can be precisely determined (<50 µg/L) in the purification filtrates and reactor trains.
- AN-RS-054Monitoring phosphate reactions in real time with Raman spectroscopy
Raman spectroscopy is a fast alternative method to detect phosphate and sulfate species in solution for optimized phosphorus fertilizer production and improved product quality.
- AN-T-224Aluminum content in coagulants and flocculants for wastewater treatment
Coagulation and flocculation are an essential part of treating both drinking water and wastewater. Aluminum salts such as aluminum sulfate and polyaluminum chloride (PAC) are often used for this purpose. For the precise application and exact dosage of the flocculant, it is important to accurately determine its aluminum content. In this Application Note, the aluminum content is accurately and reliably analyzed based on ABNT NBR 11176 using the 859 Titrotherm equipped with a Thermoprobe HF and sodium fluoride as titrant.