CN1715911A - Method for detecting corrosive sulfur content in crude oil or fraction oil - Google Patents
Method for detecting corrosive sulfur content in crude oil or fraction oil Download PDFInfo
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- CN1715911A CN1715911A CN 200410048347 CN200410048347A CN1715911A CN 1715911 A CN1715911 A CN 1715911A CN 200410048347 CN200410048347 CN 200410048347 CN 200410048347 A CN200410048347 A CN 200410048347A CN 1715911 A CN1715911 A CN 1715911A
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- Prior art keywords
- distillate
- crude oil
- powder
- sulfur content
- oil
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- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 title claims abstract description 66
- 229910052717 sulfur Inorganic materials 0.000 title claims abstract description 64
- 239000011593 sulfur Substances 0.000 title claims abstract description 64
- 239000010779 crude oil Substances 0.000 title claims abstract description 35
- 238000000034 method Methods 0.000 title claims abstract description 31
- 239000003921 oil Substances 0.000 title abstract description 9
- 239000000843 powder Substances 0.000 claims abstract description 27
- 239000002184 metal Substances 0.000 claims abstract description 24
- 229910052751 metal Inorganic materials 0.000 claims abstract description 24
- 238000006243 chemical reaction Methods 0.000 claims abstract description 21
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims abstract description 13
- 229910000975 Carbon steel Inorganic materials 0.000 claims abstract description 5
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 claims abstract description 5
- 239000010962 carbon steel Substances 0.000 claims abstract description 5
- 238000003756 stirring Methods 0.000 claims abstract description 5
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 claims abstract description 4
- 238000009835 boiling Methods 0.000 claims description 9
- 239000002283 diesel fuel Substances 0.000 claims description 2
- 239000003502 gasoline Substances 0.000 claims description 2
- 239000003350 kerosene Substances 0.000 claims description 2
- 239000010687 lubricating oil Substances 0.000 claims 1
- 230000007797 corrosion Effects 0.000 description 18
- 238000005260 corrosion Methods 0.000 description 18
- 238000005259 measurement Methods 0.000 description 8
- 230000035484 reaction time Effects 0.000 description 7
- 239000005864 Sulphur Substances 0.000 description 6
- 238000012360 testing method Methods 0.000 description 5
- 239000000706 filtrate Substances 0.000 description 4
- 239000006228 supernatant Substances 0.000 description 4
- 238000003556 assay Methods 0.000 description 3
- 239000000463 material Substances 0.000 description 3
- UCKMPCXJQFINFW-UHFFFAOYSA-N Sulphide Chemical compound [S-2] UCKMPCXJQFINFW-UHFFFAOYSA-N 0.000 description 2
- 239000009671 shengli Substances 0.000 description 2
- -1 sulphur compound Chemical class 0.000 description 2
- UMGDCJDMYOKAJW-UHFFFAOYSA-N thiourea Chemical compound NC(N)=S UMGDCJDMYOKAJW-UHFFFAOYSA-N 0.000 description 2
- 241000218691 Cupressaceae Species 0.000 description 1
- BWGNESOTFCXPMA-UHFFFAOYSA-N Dihydrogen disulfide Chemical compound SS BWGNESOTFCXPMA-UHFFFAOYSA-N 0.000 description 1
- RWSOTUBLDIXVET-UHFFFAOYSA-N Dihydrogen sulfide Chemical compound S RWSOTUBLDIXVET-UHFFFAOYSA-N 0.000 description 1
- 241000255964 Pieridae Species 0.000 description 1
- 235000008331 Pinus X rigitaeda Nutrition 0.000 description 1
- 241000018646 Pinus brutia Species 0.000 description 1
- 235000011613 Pinus brutia Nutrition 0.000 description 1
- 229910000831 Steel Inorganic materials 0.000 description 1
- XSQUKJJJFZCRTK-UHFFFAOYSA-N Urea Natural products NC(N)=O XSQUKJJJFZCRTK-UHFFFAOYSA-N 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 238000005352 clarification Methods 0.000 description 1
- 238000000975 co-precipitation Methods 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 230000007812 deficiency Effects 0.000 description 1
- 239000006185 dispersion Substances 0.000 description 1
- 238000003912 environmental pollution Methods 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- 229910000037 hydrogen sulfide Inorganic materials 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 230000007774 longterm Effects 0.000 description 1
- 239000003208 petroleum Substances 0.000 description 1
- 238000001556 precipitation Methods 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 230000000630 rising effect Effects 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
- 150000003464 sulfur compounds Chemical class 0.000 description 1
- 150000003568 thioethers Chemical class 0.000 description 1
- 238000010792 warming Methods 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
- 238000004876 x-ray fluorescence Methods 0.000 description 1
Landscapes
- Analysing Materials By The Use Of Radiation (AREA)
Abstract
The method of detecting corrosive sulfur content in crude oil or fraction oil includes making the crude oil or fraction oil react fully with metal powder at 200-400 deg c under stirring inside sealed container; and calculating the difference of sulfur content before reaction and that after reaction to determine the content of corrosive sulfur in crude oil or fraction oil. The metal powder is selected copper powder, carbon steel powder, iron powder or zinc powder. The method can determine corrosive sulfur content in crude oil or fraction oil effectively and has comparable data.
Description
Technical field
The present invention is an active sulfur Determination on content method in a kind of crude oil or the distillate, specifically, is a kind of method of measuring active sulfur content in crude oil or the distillate of reacting by metal powder and sulphur compound.
Background technology
Sulphur in crude oil or the petroleum fraction not only causes environmental pollution in process, and can the heavy corrosion process equipment.In long-term refinery's practice, the scientific worker has accumulated abundant anticorrosion experience, but aspect the sulfur corrosion prediction, does not still find easy, effective determination method.
At present, the sulfur corrosion Forecasting Methodology of widespread use is the total sulfur content of measuring in the oil sample.But total sulfur content can not be relevant with the corrosion of equipment rate fully.Some low-sulfur content crude oil, the crude oil that its corrosivity is higher than some sulfur content is also strong.
The conventional method of measuring sulfur corrosion speed is a hanging slice method, is about to the metal lacing film and immerses in the sample oil, by the weightless situation of corrosion coupon before and after the measurement corrosion, measures sulfur corrosion speed.But this method poor repeatability, the processing procedure of lacing film is very loaded down with trivial details.
Field pine and cypress etc. " petrochemical complex corrosion and protection " (2000,17 (1), 39-42) write articles the assay method that has proposed a kind of sulfur corrosion.This method places the distillate sample with copper powder, reacts a period of time under the counterflow condition that keeps the distillate boiling, then according to the variation of sulfur content in the oil sample before and after the reaction, determines the content of the active sulfur that reacts.This method is simple to operate, carries out in open system but test, and experimental temperature can not arbitrarily be controlled, and can only experimentize in the boiling temperature of distillate.Because the boiling point difference of distillate, the temperature of reaction is also different, therefore, and the data deficiency comparability.Can not measure the active sulfur content of different distillates under identical conditions.
Summary of the invention
The purpose of this invention is to provide a kind of method of measuring active sulfur content in crude oil or the distillate, this method is easy and simple to handle, the effective content of active sulfur in the simulated field operating conditions working sample.
Active sulfur Determination on content method in crude oil provided by the invention or the distillate, be included in make in the closed container crude oil or distillate 200~400 ℃, fully react with metal powder under stirring, measure the content of active sulfur in crude oil or the distillate by calculating the difference of reacting sulfur content in front and back crude oil or the distillate, described metal powder is selected from copper powder, carbon steel powder, iron powder or zinc powder.
The present invention reacts crude oil or distillate and metal powder in high-pressure sealed container, temperature of reaction can arbitrarily be controlled, be not subjected to the restriction of crude oil or distillate boiling point height, thereby increased the comparability of test data, but and the simulated field operating conditions active sulfur content in crude oil or the distillate is accurately measured.
Embodiment
Elementary sulfur in crude oil or the distillate, sulfuretted hydrogen, mercaptan sulfur isoreactivity sulphur under certain conditions, can be directly and metal react, generate water-fast precipitation.Disulfide, thioether, thiophene-type sulfide generally directly do not react with metal, but they can take place to decompose and generate active sulphur under the high temperature, thereby the corrosive attack generation is arranged.The height of these corrosive attackes and temperature is closely related, and corrosive attack is just taking place more than 200 ℃ a lot of active sulphurs.After corrosion takes place, the sulfide of formation will with the metal powder coprecipitation.Get supernatant liquor or filtrate filtered and measure total sulfur content, promptly can be considered sulfur content in the sulphur compound that has corroded with the difference of the sulfur content of sample before the unreacted.Obviously, the content and the corrosion of metal rate of the sulphur that reacts with metal powder are directly related.If with the content of reacting thiourea and the classical corrosion test result of testing laboratory, even the corrosion data of field device compares, and promptly measurable Sulfur-Containing Crude or distillate are to the corrosion situation of hardware.
Preferred 350~400 ℃ of the temperature of reaction of crude oil of the present invention or distillate and metal powder, the reaction time is 0.5~2.0 hour, preferred 0.5~1.0 hour.
The metal powder that adds in the described method should be an amount of, so that the active sulfur compound in crude oil or the distillate can total overall reaction.The metal powder amount that is added should account for 5~35 quality % of crude oil or distillate quality, preferred 5~10 quality %.
The inventive method is primarily aimed at the active sulfur assay of crude oil or distillate and sets up.Described distillate is that boiling range is 15~550 ℃ distillate, long residuum or a vacuum residuum.Described boiling range is that 15~550 ℃ distillate comprises gasoline, kerosene, diesel oil or lube cut.
The present invention adopts airtight autoclave as the reactor of measuring active sulfur content, temperature of reaction can be controlled at predetermined numerical value, therefore operating temperature that can simulated field is carried out corrosion test, and can be at the material of different parts in the device, the powder that adds this kind material in autoclave is tested, thereby can make equipment sulfur corrosion prediction more accurate.
Below by example explanation the present invention, but the present invention is not limited to this.
Sulfur content employing energy dispersion x-ray fluorescence instrument (U.S. ASOMA company produces, model 200T) in crude oil or the distillate in the example
Example 1
Introducing 30 gram boiling ranges are 15~350 ℃ distillate sample in having the airtight autoclave of stirring and temperature, pressure controller, and the sample sulfur content is 4220ppm.Add 5 gram iron powders, be warming up to set point of temperature reaction 1 hour under stirring.With air cooling, make the high pressure temperature in the kettle reduce to 150 ℃ then, again with chilled water with the autoclave cool to room temperature, when treating that the still external and internal pressure is identical, open autoclave, take out sample filtering, filtrate is left standstill clarification, get supernatant liquor and measure sulfur content, the measurement result under the differential responses temperature sees Table 1.
As known from Table 1, the content of active sulfur is less under lower temperature of reaction, and along with the rising of temperature, the quantity of active sulfur increases gradually, and when temperature of reaction during greater than 350 ℃, the content of active sulfur tends towards stability.Therefore, the optimal reaction temperature of mensuration active sulfur content is 350~400 ℃.
Example 2
This case expedition reaction time is to the influence of measurement result.
The method of pressing example 1 is measured the content of active sulfur in the distillate, and the control temperature of reaction is 350 ℃, and the active sulfur content that the differential responses time is measured down sees Table 2.
As shown in Table 2, iron powder and oil sample reaction time are too short, because reaction is insufficient, cause measurement result on the low side, after the reaction time surpasses 1.0 hours, prolong the reaction time for not obviously influence of measurement result.Therefore the suitable reaction time should be more than 1.0 hours.
Example 3
This case expedition iron powder dosage is to the influence of measurement result.
The method of pressing example 1 is measured the active sulfur content of distillate, adds the iron powder of different amounts in distillate respectively, and the control temperature of reaction is 350 ℃, and the time is 1 hour, and measurement result sees Table 3.Table 3 data presentation, the addition of iron powder are 2~10 grams, just account for 6.7 quality % of distillate sample size when above, and the active sulfur assay of distillate is not had obvious influence.
Example 4
The method of pressing example 1 is measured the active sulfur content of distillate, adds the metal powder of 5 gram unlike materials in distillate respectively, and the control temperature of reaction is 350 ℃, and the time is 1 hour, and measurement result sees Table 4.
As can be seen from Table 4, outside the de-carbon comminuted steel shot, the active sulfur content that adopts other metal powder to measure is more approaching.On the other hand, the carbon steel powder has stronger sulfur corrosion resistant ability than other metal powder.
Example 5
The method of pressing example 1 is measured the active sulfur content of Shengli crude, sulfur content is 9770ppm in the described crude oil, the control temperature of reaction is 350 ℃, time is 1 hour, after the iron powder reaction, it is 9596ppm that the supernatant liquor of getting clear filtrate records sulfur content, and active sulfur content is 184ppm in this crude oil, accounts for 1.88 quality % of total sulfur content.
Buy example 6
The method of pressing example 1 is measured the active sulfur content of Shengli crude long residuum (boiling point>350 ℃), sulfur content is 11302ppm in the described long residuum, the control temperature of reaction is 350 ℃, time is 1 hour, after the iron powder reaction, it is 10918ppm that the supernatant liquor of getting clear filtrate records sulfur content, and active sulfur content is 384ppm in this crude oil, accounts for 3.40 quality % of total sulfur content.
Table 1
Table 2
Reaction time, minute | 10 | 30 | 60 | 90 | 120 |
Active sulfur content, ppm | 97 | 124 | 151 | 157 | 161 |
Table 3
The iron powder addition, gram | 2 | 5 | 10 |
Active sulfur content, ppm | 157 | 154 | 155 |
Table 4
The metal powder that uses | Copper powder | Zinc powder | Iron powder | The carbon steel powder |
Active sulfur content, ppm | 159 | 160 | 156 | 101 |
Claims (6)
1, active sulfur Determination on content method in a kind of crude oil or the distillate, be included in make in the closed container crude oil or distillate 200~400 ℃, fully react with metal powder under stirring, measure the content of active sulfur in crude oil or the distillate by calculating the difference of reacting sulfur content in front and back crude oil or the distillate, described metal powder is selected from copper powder, carbon steel powder, iron powder or zinc powder.
2, in accordance with the method for claim 1, the temperature of reaction that it is characterized in that described crude oil or distillate and metal powder is 350~400 ℃.
3, in accordance with the method for claim 1, it is characterized in that the time that crude oil or distillate and metal powder react is 0.5~2.0 hour.
4, in accordance with the method for claim 1, it is characterized in that described distillate is that boiling range is 15~550 ℃ distillate, long residuum or a vacuum residuum.
5,, it is characterized in that described distillate is gasoline, kerosene, diesel oil or lubricating oil according to claim 1 or 4 described methods.
6, in accordance with the method for claim 1, it is characterized in that the metal powder that adds accounts for 5~35 quality % of crude oil or distillate quality.
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CNB200410048347XA CN100363742C (en) | 2004-06-29 | 2004-06-29 | Method for detecting corrosive sulfur content in crude oil or fraction oil |
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CNB200410048347XA CN100363742C (en) | 2004-06-29 | 2004-06-29 | Method for detecting corrosive sulfur content in crude oil or fraction oil |
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Cited By (7)
Publication number | Priority date | Publication date | Assignee | Title |
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CN101995376A (en) * | 2009-08-18 | 2011-03-30 | 华东电力试验研究院有限公司 | Judgment method of sulfur corrosion of coil material in oil-filled electrical equipment |
CN102116769A (en) * | 2011-03-03 | 2011-07-06 | 天津出入境检验检疫局化矿金属材料检测中心 | Method for measuring elemental sulfur content in gypsum and product thereof |
CN101614716B (en) * | 2008-06-26 | 2011-09-07 | 中国石油大学(华东) | Methods for indirectly determining sulfur content of oil field waste water and analyzing valence of sulfur |
CN102608194A (en) * | 2012-02-24 | 2012-07-25 | 北京盈胜泰科技术有限公司 | Online detecting device for active sulfur in liquid oil |
CN101354384B (en) * | 2007-07-27 | 2012-07-25 | 中国石油化工股份有限公司 | Method and instrument for quantitatively analyzing trace amount acetylene hydrocarbon in carbon four fractions |
CN103018398A (en) * | 2012-11-26 | 2013-04-03 | 武汉大学 | Quantitative detection method for corrosive sulphur in insulating oil |
CN104007101A (en) * | 2014-05-26 | 2014-08-27 | 中国兵器工业集团第五三研究所 | Method for measuring sulfur content in fuel oil through inductively coupled plasma-atomic emission spectrometry (ICP-AES) method |
Family Cites Families (4)
Publication number | Priority date | Publication date | Assignee | Title |
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DE19741809B4 (en) * | 1997-09-23 | 2005-09-15 | Ech Elektrochemie Halle Gmbh | Method for total sulfur determination |
CN1191473C (en) * | 2000-03-03 | 2005-03-02 | 中国石油化工集团公司 | Method for measuring total active sulfur in petroleum fractions |
CN1238245C (en) * | 2001-06-16 | 2006-01-25 | 郑凌峰 | Purifying method for sodium hydrosulfide |
CN1204231C (en) * | 2001-12-30 | 2005-06-01 | 中国石化集团齐鲁石油化工公司 | Desulfurization process of gasoline |
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2004
- 2004-06-29 CN CNB200410048347XA patent/CN100363742C/en not_active Expired - Lifetime
Cited By (9)
Publication number | Priority date | Publication date | Assignee | Title |
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CN101354384B (en) * | 2007-07-27 | 2012-07-25 | 中国石油化工股份有限公司 | Method and instrument for quantitatively analyzing trace amount acetylene hydrocarbon in carbon four fractions |
CN101614716B (en) * | 2008-06-26 | 2011-09-07 | 中国石油大学(华东) | Methods for indirectly determining sulfur content of oil field waste water and analyzing valence of sulfur |
CN101995376A (en) * | 2009-08-18 | 2011-03-30 | 华东电力试验研究院有限公司 | Judgment method of sulfur corrosion of coil material in oil-filled electrical equipment |
CN102116769A (en) * | 2011-03-03 | 2011-07-06 | 天津出入境检验检疫局化矿金属材料检测中心 | Method for measuring elemental sulfur content in gypsum and product thereof |
CN102608194A (en) * | 2012-02-24 | 2012-07-25 | 北京盈胜泰科技术有限公司 | Online detecting device for active sulfur in liquid oil |
CN102608194B (en) * | 2012-02-24 | 2014-09-10 | 北京盈胜泰科技术有限公司 | Online detecting device for active sulfur in liquid oil |
CN103018398A (en) * | 2012-11-26 | 2013-04-03 | 武汉大学 | Quantitative detection method for corrosive sulphur in insulating oil |
CN103018398B (en) * | 2012-11-26 | 2014-12-03 | 武汉大学 | Quantitative detection method for corrosive sulphur in insulating oil |
CN104007101A (en) * | 2014-05-26 | 2014-08-27 | 中国兵器工业集团第五三研究所 | Method for measuring sulfur content in fuel oil through inductively coupled plasma-atomic emission spectrometry (ICP-AES) method |
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