US3598531A - Method for determining sulfur as sulfur dioxide - Google Patents
Method for determining sulfur as sulfur dioxide Download PDFInfo
- Publication number
- US3598531A US3598531A US760976A US3598531DA US3598531A US 3598531 A US3598531 A US 3598531A US 760976 A US760976 A US 760976A US 3598531D A US3598531D A US 3598531DA US 3598531 A US3598531 A US 3598531A
- Authority
- US
- United States
- Prior art keywords
- sulfur
- nitrogen
- sodium azide
- titration
- iodometric
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- 238000000034 method Methods 0.000 title abstract description 31
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 title abstract description 28
- 239000011593 sulfur Substances 0.000 title abstract description 28
- 229910052717 sulfur Inorganic materials 0.000 title abstract description 28
- RAHZWNYVWXNFOC-UHFFFAOYSA-N Sulphur dioxide Chemical compound O=S=O RAHZWNYVWXNFOC-UHFFFAOYSA-N 0.000 title description 14
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 abstract description 40
- PXIPVTKHYLBLMZ-UHFFFAOYSA-N Sodium azide Chemical compound [Na+].[N-]=[N+]=[N-] PXIPVTKHYLBLMZ-UHFFFAOYSA-N 0.000 abstract description 32
- 229910052757 nitrogen Inorganic materials 0.000 abstract description 20
- 238000004448 titration Methods 0.000 abstract description 10
- 150000001805 chlorine compounds Chemical class 0.000 abstract description 7
- -1 CRUDES Substances 0.000 abstract description 6
- 239000007787 solid Substances 0.000 abstract description 5
- 239000003921 oil Substances 0.000 abstract description 3
- 239000003348 petrochemical agent Substances 0.000 abstract description 3
- 239000003792 electrolyte Substances 0.000 abstract description 2
- 239000000460 chlorine Substances 0.000 description 10
- ZCYVEMRRCGMTRW-UHFFFAOYSA-N 7553-56-2 Chemical compound [I] ZCYVEMRRCGMTRW-UHFFFAOYSA-N 0.000 description 9
- 229910052740 iodine Inorganic materials 0.000 description 9
- 239000011630 iodine Substances 0.000 description 9
- ZAMOUSCENKQFHK-UHFFFAOYSA-N Chlorine atom Chemical compound [Cl] ZAMOUSCENKQFHK-UHFFFAOYSA-N 0.000 description 8
- 229910052801 chlorine Inorganic materials 0.000 description 8
- 210000004027 cell Anatomy 0.000 description 7
- 238000003869 coulometry Methods 0.000 description 7
- YXFVVABEGXRONW-UHFFFAOYSA-N Toluene Chemical compound CC1=CC=CC=C1 YXFVVABEGXRONW-UHFFFAOYSA-N 0.000 description 6
- 239000000126 substance Substances 0.000 description 5
- 238000004458 analytical method Methods 0.000 description 4
- 239000003208 petroleum Substances 0.000 description 4
- 239000000523 sample Substances 0.000 description 4
- 229910052783 alkali metal Inorganic materials 0.000 description 3
- 239000003209 petroleum derivative Substances 0.000 description 3
- NLKNQRATVPKPDG-UHFFFAOYSA-M potassium iodide Chemical compound [K+].[I-] NLKNQRATVPKPDG-UHFFFAOYSA-M 0.000 description 3
- 239000010453 quartz Substances 0.000 description 3
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N silicon dioxide Inorganic materials O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 3
- 239000002904 solvent Substances 0.000 description 3
- VEXZGXHMUGYJMC-UHFFFAOYSA-M Chloride anion Chemical compound [Cl-] VEXZGXHMUGYJMC-UHFFFAOYSA-M 0.000 description 2
- 150000001340 alkali metals Chemical class 0.000 description 2
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 2
- 150000001540 azides Chemical class 0.000 description 2
- 229910017464 nitrogen compound Inorganic materials 0.000 description 2
- 150000002830 nitrogen compounds Chemical class 0.000 description 2
- 239000001301 oxygen Substances 0.000 description 2
- 229910052760 oxygen Inorganic materials 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 1
- 239000003153 chemical reaction reagent Substances 0.000 description 1
- 238000002485 combustion reaction Methods 0.000 description 1
- 238000009839 combustion train Methods 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 238000004817 gas chromatography Methods 0.000 description 1
- 230000006698 induction Effects 0.000 description 1
- 210000004457 myocytus nodalis Anatomy 0.000 description 1
- 238000011017 operating method Methods 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 238000002203 pretreatment Methods 0.000 description 1
- 238000010998 test method Methods 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N31/00—Investigating or analysing non-biological materials by the use of the chemical methods specified in the subgroup; Apparatus specially adapted for such methods
- G01N31/16—Investigating or analysing non-biological materials by the use of the chemical methods specified in the subgroup; Apparatus specially adapted for such methods using titration
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
- G01N33/26—Oils; Viscous liquids; Paints; Inks
- G01N33/28—Oils, i.e. hydrocarbon liquids
- G01N33/2835—Specific substances contained in the oils or fuels
- G01N33/287—Sulfur content
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T436/00—Chemistry: analytical and immunological testing
- Y10T436/11—Automated chemical analysis
- Y10T436/115831—Condition or time responsive
- Y10T436/116664—Condition or time responsive with automated titrator
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T436/00—Chemistry: analytical and immunological testing
- Y10T436/18—Sulfur containing
- Y10T436/188—Total or elemental sulfur
Definitions
- the improved method is applicable to oils, crudes, solids, and petrochemicals.
- our invention provides an improvement in the method for determining sulfur as sulfur dioxide in petroleum, petrochemical, and chemical products utilizing the iodometric or microcoulometric methods of sulfur determination wherein a titration cell containing an iodine-containing titration solvent is utilized, said improvement comprising overcoming chloride compound and nitrogen interferences in said method by adding sodium azide to the titration solvent thereby preferentially reacting the chloride compounds and nitrogen compounds without reacting the iodine.
- sodium azide added to an iodine-containing titration solvent is effective in overcoming the interference from chloride compounds and nitrogen where it is encountered in the iodometric determination of sulfur as sulfur dioxide.
- ASTM Method D 1552 modified by the improvement of my invention the relative error in the presence of about 20% chlorine and about 8% nitrogen was 2.2%; the relative standard deviation was 2% for the 1 to 20% sulfur level.
- the relative error in the presence of about 8% nitrogen was about -1.0% and the relative standard deviation was 1.1%.
- samples analyzed included oils, crudes, and solids and included sulfur levels ranging from about 0.1 to about 20%.
- the coulometric method is more sensitive and has better precision than the volumetric method although the two methods are comparable in accuracy, even in the presence of large amounts of nitrogen and chlorine compounds provided the improvement of my invention, namely, the addition of sodium azide to the titration solvent is utilized.
Landscapes
- Chemical & Material Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Pathology (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- Engineering & Computer Science (AREA)
- Immunology (AREA)
- Physics & Mathematics (AREA)
- Molecular Biology (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Oil, Petroleum & Natural Gas (AREA)
- Food Science & Technology (AREA)
- Medicinal Chemistry (AREA)
- Investigating Or Analyzing Non-Biological Materials By The Use Of Chemical Means (AREA)
Abstract
CHLORIDE COMPOUND AND NITROGEN INTERFERENCES TO THE IODOMETRIC AND/OR MICROCOULOMETRIC METHODS OF SULFUR DETERMINATION ARE OVERCOME BY ADDING SODIUM AZIDE TO THE TITRATION CELL ELECTROLYTE. THE IMPROVED METHOD IS APPLICABLE TO OILS, CRUDES, SOLIDS, AND PETROCHEMICALS.
Description
United States Patent 015cc U.S. Cl. 23-230 2 Claims ABSTRACT OF THE DISCLOSURE Chloride compound and nitrogen interferences to the iodometric and/or microcoulometric methods of sulfur determination are overcome by adding sodium azide to the titration cell electrolyte. The improved method is applicable to oils, crudes, solids, and petrochemicals.
BACKGROUND OF THE INVENTION The presence of chlorine in concentrations in excess of 1.0% and nitrogen in excess of 0.1% may interfere in the iodometric determination of sulfur in petroleum and chemical products using the classical iodometric ASTM Method of Test for Sulfur in Petroleum Products (High Temperature Method) (D 1552-64) or its equivalent. In the case of nitrogen, the extent of such interference is dependent on the type of nitrogen compound as well as the amount present. The interference results from oxidation of nitrogen to oxides of nitrogen and chloride to chlorine, each of which reacts with potassium iodide in the iodometric titration to liberate iodine. Sulfur is oxidized in the method to sulfur dioxide which is measured by the consumption of iodine in the titration. Therefore, the effect of the presence of nitrogen and chlorine is to cause low, or even negative results. Since chloride and especially nitrogen are commonly associated with sulfur in petroleum products, petrochemicals, and chemicals, this interference constitutes a very severe limitation of the method.
Therefore, it is one object of this invention to provide an improved method for determining sulfur as sulfur dioxide in petroleum and chemical products. It is another object of this invention to provide a method of overcoming nitrogen and chloride compound interferences in the classical methods of sulfur determination so that the inherent limitations of the old methods are eliminated.
In one embodiment, our invention provides an improvement in the method for determining sulfur as sulfur dioxide in petroleum, petrochemical, and chemical products utilizing the iodometric or microcoulometric methods of sulfur determination wherein a titration cell containing an iodine-containing titration solvent is utilized, said improvement comprising overcoming chloride compound and nitrogen interferences in said method by adding sodium azide to the titration solvent thereby preferentially reacting the chloride compounds and nitrogen compounds without reacting the iodine.
SUMMARY OF THE INVENTION AND EXAMPLE In order to overcome the interference from nitrogen, several scrubbers and pretreatments were evaluated. From this experimentation, it was found that an alkali metal 3,598,531 Patented Aug. 10, 1971 azide, and preferably sodium azide, added directly to a titration vessel, appeared to react rapidly and preferentially with chlorine and the oxides of nitrogen. The presence of sodium azide did not appear to otherwise participate in or interfere with the iodometric determination of sulfur as sulfur dioxide. To check these preliminary observations, several standards were analyzed with and without the presence of sodium azide in the titration vessel of the volumetric-type sulfur determinator, and in the coulometric-type sulfur analyzer as described in Adams et al., Improved Sulfur-Reacting Microcoulometric Cell for Gas Chromatography, Analytical Chemistry, vol. 38, 1966, p. 1094.
An induction furnace and automatic volumetric sulfur apparatus was used where the test method called for a volumetric-type sulfur determinator. A microcoulometer with a 300 P cell Was used for iodine generation where the method called for a coulometric-type sulfur analyzer. The combustion train used with the microcoulometer employed a 13 mm. outside diameter, 10 mm. inside diameter, ll5-cm. quartz tube filled with quartz chips, coarsely ground to pass a inch screen. The quartz tube was maintained at 1150 C. using two heavy duty combustion furnaces in series. Oxygen carrier fiow rates from 20 to 300 mL/min. were preferred, although a flow of 50 ml./ min. was normally used with this apparatus. Sodium azide (practical) was used as the reagent.
For the coulometric analyses, 3 to 5 mg. of solid sodium azide was added to the titration cell solvent. In order to equilibrate the system prior to the first determination, a sample of S0 gas was injected or a sample of the product was burned. A fresh portion of sodium azide was added whenever the cell solvent was changed.
For the volumetric-type determinations, 500 to 700 mg. of solid sodium azide was added to the titration cell solvent prior to each determination. No other changes in the normal operating procedures for the method are required for either approach to the iodometric sulfur analysis. To determine the efficacy of sodium azide addition in overcoming nitrogen and chlorine interference, several standards and samples were analyzed with and without added sodium azide. The data in Table 1 comparing both the coulometric and volumetric methods were obtained:
Therefore, it can be concluded that sodium azide added to an iodine-containing titration solvent is effective in overcoming the interference from chloride compounds and nitrogen where it is encountered in the iodometric determination of sulfur as sulfur dioxide. For ASTM Method D 1552 modified by the improvement of my invention, the relative error in the presence of about 20% chlorine and about 8% nitrogen was 2.2%; the relative standard deviation was 2% for the 1 to 20% sulfur level. For the coulometric sulfur method, the relative error in the presence of about 8% nitrogen was about -1.0% and the relative standard deviation was 1.1%. As shown below, samples analyzed included oils, crudes, and solids and included sulfur levels ranging from about 0.1 to about 20%. The coulometric method is more sensitive and has better precision than the volumetric method although the two methods are comparable in accuracy, even in the presence of large amounts of nitrogen and chlorine compounds provided the improvement of my invention, namely, the addition of sodium azide to the titration solvent is utilized.
TABLE 1.ANALYSIS OF STANDARDS AND SAMPLES WITH AND WITHOUT ADDED SODIUM AZIDE Percent sulfur found NaNa added Volumetric Percent present No NaNs added 01 S Volumetric Coulometric Coulometrie 1 Black Negative Sample 0 3028278382 do-10100431 m 22 2 L5 5 A-0 1 1 7 3 1 1011 2 2 2 L Black do 78 n u n m m m n u n n w u U n d e "m M m m am mmm mm ue. 1 Ma m0 0 3 n. H d S v. u nn wn B mn H 86H a tz h S S 1 Ye M C CBC Atv l Generates iodine; gives black solution in the volumetric method and a negative response in the case of the coulometric method it much nitrogen is present.
2 Oxygen bomb analysis, ASTM Method of Test for Sulfur in Petroleum Products by the Bomb Method (D 129-64).
References Cited UNITED STATES PATENTS I claim:
1. In a method for determining sulfur as sulfur dioxide in petroleum, petrochemical, or chemical products 25 which contain sulfur, nitrogen and chlorine utilizing the 2669504 2/1954 Halvorson 6t 23230PC iodometric or microcoulometric methods of sulfur deter- OTHER REFERENCES Pardue et al., Chem. Abstr. 58, 7125d (1963).
mination wherein a titration cell containing an iodine-containing titration solvent is utilized to measure sulfur di- MORRIS O. WOLK, Primary Examiner R. M. REESE, Assistant Examiner which comprises adding an alkali metal azide to said titration solvent thereby preferentially reacting said chlorine and nitrogen without reaction of said iodine.
US. Cl. X.R.
2. The method of claim 1 wherein said alkali metal 35 azide is sodium azide. 204-1
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US76097668A | 1968-09-19 | 1968-09-19 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US3598531A true US3598531A (en) | 1971-08-10 |
Family
ID=25060740
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US760976A Expired - Lifetime US3598531A (en) | 1968-09-19 | 1968-09-19 | Method for determining sulfur as sulfur dioxide |
Country Status (1)
| Country | Link |
|---|---|
| US (1) | US3598531A (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3853474A (en) * | 1972-10-10 | 1974-12-10 | Itt | Method of burning combustible fluids for further analysis |
| US4172705A (en) * | 1978-04-12 | 1979-10-30 | Envirotech Corporation | Process and apparatus for sulfur analysis |
| US4211748A (en) * | 1978-01-23 | 1980-07-08 | International Telephone And Telegraph Corporation | Stack gas analyzer and thermal oxidation device therefor |
| US4325911A (en) * | 1978-01-23 | 1982-04-20 | International Telephone And Telegraph Corporation | Stack gas analyzer and thermal oxidation device therefor |
| CN103389332A (en) * | 2013-07-26 | 2013-11-13 | 江苏东华分析仪器有限公司 | Electrolytic tank for determining total content of sulphur by adopting microcoulometric method |
-
1968
- 1968-09-19 US US760976A patent/US3598531A/en not_active Expired - Lifetime
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3853474A (en) * | 1972-10-10 | 1974-12-10 | Itt | Method of burning combustible fluids for further analysis |
| US4211748A (en) * | 1978-01-23 | 1980-07-08 | International Telephone And Telegraph Corporation | Stack gas analyzer and thermal oxidation device therefor |
| US4325911A (en) * | 1978-01-23 | 1982-04-20 | International Telephone And Telegraph Corporation | Stack gas analyzer and thermal oxidation device therefor |
| US4172705A (en) * | 1978-04-12 | 1979-10-30 | Envirotech Corporation | Process and apparatus for sulfur analysis |
| CN103389332A (en) * | 2013-07-26 | 2013-11-13 | 江苏东华分析仪器有限公司 | Electrolytic tank for determining total content of sulphur by adopting microcoulometric method |
| CN103389332B (en) * | 2013-07-26 | 2016-04-27 | 江苏东华分析仪器有限公司 | Total sulfur content micro-coulometric determination electrolytic cell |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Nadkarni | Multitechnique multielemental analysis of coal and fly ash | |
| Safavi et al. | Flow injection chemiluminescence determination of hydrazine | |
| JPH0643967B2 (en) | Fluorometric concentration measuring method and measuring device | |
| Robinson | Determination of lead in gasoline by atomic absorption spectroscopy | |
| Lomako et al. | Sulfate-selective electrode and its application for sulfate determination in aqueous solutions | |
| Connors | The Karl Fischer titration of water | |
| US3598531A (en) | Method for determining sulfur as sulfur dioxide | |
| US4172705A (en) | Process and apparatus for sulfur analysis | |
| Sladkov et al. | Assignment of complex species by affinity capillary electrophoresis: The case of Th (IV)‐desferrioxamine B | |
| US3585000A (en) | Method for determining sulfur as sulfur dioxide | |
| Llavero et al. | Improved trihydroxyindole method for the simultaneous stopped-flow spectrofluorimetric determination of epinephrine and norepinephrine in urine | |
| Weisz et al. | Double indication in catalytic-kinetic analysis: simultaneous photometric and thermometric indication of the iodine-azide reaction in closed and flow systems | |
| Pleban et al. | Determination of lead in whole blood and urine using Zeeman effect flameless atomic absorption spectroscopy | |
| Britton et al. | Analysis of electrocatalytic processes with following electron transfer by a potential step method. Theory and application to the phenanthrene-octyl chloride system | |
| Mottola et al. | Use of metal ion catalysis in detection and determination of microamounts of complexing agents. Catalimetric titration of cyanide ion | |
| US4196056A (en) | Ion selective electrode analysis | |
| Clysters et al. | Potentiometric determinations with the silver sulfide membrane electrode: Part II. Determination of Sulfur Compounds | |
| Owerbach | Analysis and sample stability of cyanides in industrial effluents | |
| Morosanova et al. | Length-of-stain indicator tubes for the determination of metals in water and solutions | |
| Lejeune et al. | Polarographic determination of Sn (II) in samples containing Sn (IV) such as in 99m-Technetium radiopharmaceutical kits | |
| Crumpton et al. | Determination of nitrate in water using ammonia probes and reduction by titanium (III) | |
| Rojas‐Romo et al. | A Comparative Study of 8‐Hydroxyquinoline and 8‐Hydroxyquinoline‐5‐sulfonic Acid for Antimony (III) Determination by AdSV. Substituent Effect on Sensitivity II | |
| US3434800A (en) | Process for determining mercury in geologic materials | |
| Gehring et al. | Determination of sodium nitrate in sodium nitrite by selective ion electrode measurement | |
| Jaselskis et al. | Titrimetric Determination of Semimicro Amounts of Sulfate in Presence of Phosphate. |