Wednesday, September 2, 2009

Kromathography

Khromatography
Although rather [do] not too clear, contribution of kromatografi [at] growth of modern chemistry cannot be placed in the background. Without technique of kromatografi, pure compound sintesis ( or almost purification) will very difficult , and in most cases, near enough impossible.
[In] early century of ke-20, chemical [of] Russia of Mikhail Sem├źnovich Tsvet ( 1872-1919) preparing filled column with carbonate calcium serbuk, and him of poured [by] crop pigment mixture which dissolved in ether. By surprising, pigment dissociate and form chromatic coat alongside column. He names kromatografi [at] this new dissociation technique ( 1906). Later;Then is chemical the than Swiss Richard Martin Willst├Ątter ( 1872-1942) applying this technique to research into him namely khlorofil to show this technique benefit, and since then many attentions passed to kromatografi.
Kromatografi is technique to dissociate mixture become the component of constructively difference of[is nature of physical of[is each component. used [to] appliance consist of column which was in it filled in stasioner fasa ( dilution or padatan). Mixture added to column of back part one and mixture will make a move constructively pengemban the compatibleness ( car fasa). Tired dissociation by fast difference go down the each component in columns, determined by strength of coefficient or adsorpsi of partisi [among/between] car fasa and of fasa silent ( stationer).
Especial component [of] kromatografi is stationer fasa and of fasa and car of kromatografi divided to become some types base on type of fasa mechanism and car dissociation of him, like shown in Tables 12.1.
Tabel 12.1 Klasifikasi kromatografi
Kriteria Nama
Fasa mobil Kromatografi cair, kromatografi gas
Kromatografi adsorpsi, kromatografi partisi
Mekanisme Kromatografi pertukaran ion
kromatografi gel
Fasa stationer Kromatografi kolom, kromatografi lapis tipis,
kromatografi kertas

Some example [of]s of kromatografi which was often used [by] [in] laboratory given hereunder.
B. Principal Partisi Kromatografi
[of] partisi kromatografi can be explained with law of partisi which earn to be applied [at] studied multicomponent system [in] shares before all. In partisi kromatografi, ekstraksi happened recuring in once process. On trial, dissolve Iihat vitamin distributed [by] [among/between] stationer fasa and of fasa car. Stationer Fasa in most cases pelarut of diadsorbsi [at] and adsorben of fasa cars is molecule of pelarut filling room between particle which was tar of adsorbsi.
Typical example [of] [of] partisi kromatografi is used column kromatografi wide [of] because is very efficient for the dissociation of organic compound ( Picture 12.3).

His column ( tube of gela) filled with materials like alumina, gel silica or mixed with extract [is] adsorben, and pasta of filled in into column. condensation of Sampel is later;then filled in into column of[is from the top (of) so that diasorbsi sammpel by adsorben. Later;Then pelarut ( car fasa; carrier) added [by] drip for the shake of drip of[is from the top (of) column. dissolve Partisi Iihat vitamin take place [in] pelarut which go down downwards ( car fasa) and pelarut which is teradsorbsi by adsorben ( stationer fasa).
During journey go down, dissolve Iihat vitamin will experience of process of adsorpsi and of partisi repeatedly. Accelerate degradation differ to the each dissolve Iihat vitamin and base on coefficient of partisi the each dissolve Iihat vitamin. Finally, dissolve Iihat vitamin will be dissociated to form some coats. Finally, each coat caressed with pelarut which suited for giving pure spesimen [of] him. Assess R defined to every Iihat vitamin of etralrut with equation following.
R = ( gone through [by] distance [is] dissolve Iihat vitamin) / ( gone through [by] distance [is] pelarut / car fasa)

Gambar 12.3 Diagram skematik kromatografi
b. Paper Chromatography
Paper Mechanism dissociation Kromatografi with principal paper kromatografi [of] him [is] equal to mechanism [at] column kromatografi. Adsorben in paper kromatografi is paper filter, namely cellulose. Sampel to be analysed isn't it to paper back part which was later;then hung in place of. Later;Then paper base filter to be plunged into pelarut filling base of[is place of. Car Fasa ( just pelarut) earn immeasurable. Water, etanol, sour [of] this Iihat vitamins mixture or acetate can be used. Paper Kromatografi applied for the analysis of sour mixture [of] amino with outstanding success. Because acid of amino measure up to very, and sour**acid*******s [of] dissolve amino in water and not volatile ( not possible (to) didistilasi), dissociation of acid of amino is hardest problem which faced [by] chemistry [in] final [of] century 19 and early century 20. Becoming invention of paper kromatografi is very good news for them. Kimiawan English of Richard Laurence Millington Synge ( 1914-1994) is first person using sour analysis method [of] amino with paper kromatografi. sour Mixture moment [of] amino take a ride paper sheet vertically caused by capillary phenomenon, sour partisi [of] amino [among/between] car fasa and of fasa silent ( air) which is teradsorbsi [at] cellulose take place repeatedly. armpit of Pelarut tired [of] back part of process paper discontinued. Each;Every acid of amino peripatetic of starting points as long as selected distance. Of value of R, each acid of amino identified. Paper Kromatografi of dua-dimensi ( 2D) using wide [of] paper [is] not small sheet, and the him of processed by dua dimension by two solvent

Gambar 12.4 Contoh hasil kromatografi kertas pigmen dari
www.indigo.com/ science-supplies/filterpaper. html
c. Gas Chromatography .
Mixture gas can be dissociated with gas chromatography .. Stationer Fasa can in the form of padatan ( gas-padat kromatografi) or dilution ( gas-cair kromatografi). Generally, for the kromatografi of gas-padat, small number of inert padatan for example activation carbons, activated alumina, gel silica or molecular filter filled in into metal tube furl the length ( 2-10 m) and attenuate. Car Fasa are gas a kind of hydrogen, argon or nitrogen and referred [as] [by] carrier gas. Dissociation of gas have dot [to] boiled to lower like oxygen, carbon monoxide and conducive dioxide carbon with this technique. In case of kromatografi gas-cair, ester like dodesilsulfat ftalil which is diadsorbsi on the surface of activated alumina, gel silica or molecular buffer, used as [by] [of] silent fasa and filled in to in columns. Compound mixture which is is volatile to be mixed with carrier gas inseminated to in columns, and each;every compound of dipartisi [among/between] gas fasa ( and mobil) of fasa liquid ( diam) follow law of partisi. less dissolve compound in silent fasa will go out in advance. This method specially very good to analyse volatile organic compound like ester and hydrocarbon. Analysis crude oil and oil of atsiri in fruit have is successfully [done/conducted] with this technique. Dissociation efficiency determined with level of interaction [among/between] sampel and his dilution. Is suggested to try liquid fasa [of] standard knew effective to various compound. Pursuant to this result, more special dilution later;then can be selected. Method detect him, will influence sensitively [of] this technique. selected method will hinge what is target of or analisik of preparatif..
D. HPLC
Recently, for purification ( for example for sintesis) big scale organic compound, HPLC ( chromatography liquid precision high or of high performance of chromatography liquid) is extensively used. incessant La Iihat vitamin Bi with pelarut the compatibleness, the Iihat vitamin can be analysed. this Technique characteristic is usage of high pressure to send car fasa into column. given high pressure, fast and dissociation efficiency can be improved bigly. Gel silica or of oktadesilsilan which tied [at] gel silica used as [by] stationer fasa. liquid Stationer Fasa not popular. Column used for shorter HPLC than column used for gas chromatography .. Most shorter columns from 1 m. Kromatografi ion exchanger use ion exchanger materials as silent fasa and have succeeded to be used for the analysis of cation, anion and organic ion.
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