16 research outputs found
The Use of 13C NMR Spectroscopy and Comprehensive Two-dimensional Gas Chromatography, GCĆGC, for Identification of Compounds Involved in Diesel Fuel Oxidative Behavior
An approach has been proposed combining one dimensional inverse gated 13C NMR spectroscopy
and a comprehensive two dimensional gas chromatography (GCĆGC) to analyze diesel fuels prior and
after oxidation under the standard conditions. Classes of hydrocarbons present before and after oxidation
have been identified and quantified. A decrease in aromatic iso- and n-paraffinic hydrocarbons and an increase
in the total saturated hydrocarbons have been observed after oxidation. In that respect NMR spectroscopy
has potential to be used as standard method for determination of oxidation stability. Furthermore,
GCĆGC has been applied to identify compounds involved in the formation of sediments during oxidation.
Obtained results have shown that hydrocarbon composition, especially the normal paraffin content play a
role in the formation of sediments in these distillate fuels. This is important since sediments may influence
the quality of diesel fuels. (doi: 10.5562/cca1874
FCC GASOLINE RESEARCH OCTANE NUMBER DETERMINATION BY GAS CHROMATOGRAPHY
Sažetak
Benzin iz procesa fluid katalitiÄkog krekinga (FCC) pripada grupi benzina s visokim sadržajem nezasiÄenih ugljikovodika. Zbog njegovog velikog znaÄaja pri namjeÅ”avanju komercijalnih motornih benzina, vrlo je interesantan za istraživanje korelacija sastava s fizikalno-kemijskim svojstvima, posebice s oktanskim brojem.
U ovom radu koristili smo plinsku kromatografiju visokog razluÄivanja za separaciju viÅ”e od 350 komponenata sadržanih u FCC benzinu. Pri odabiru ulaznih parametara za regresijsku analizu velika koliÄina nezasiÄenih ugljikovodika predstavljala je specifiÄan problem zbog znatnog broja nerazluÄenih ili loÅ”e razluÄenih pikova.
U radu je predstavljen novi pristup odabiru ulaznih parametara za postavljanje korelacije kemijskog sastava i istraživaÄkog oktanskog broja FCC benzina. Postupak ukljuÄuje dva stupnja odabira i grupiranja odijeljenih komponenata koji se osniva na faktorima koji imaju najveÄi utjecaj na istraživaÄki oktanski broj.Abstract
The FCC gasoline belongs to the group of gasolines with a high content of unsaturated hydrocarbons. Because of its significance as blending component, the correlations connecting composition and physical properties, especially the octane number, are of great significance.
For the separation of more than 350 components, the high-resolution gas chromatography is used. The main problem was the high content of unsaturated hydrocarbons because of a considerable number of unseparated and poorly separated peaks.
For the selection of parameters to be correlated, a new approach has been used. The method includes two steps for selection and grouping of separated components, based on factors with the highest influence on RON
Chemical Composition and Physical Properties of āPale Yellowā Naphtalan
The Pale Yellow (PY) Naphthalan is potentially a new treatment modality for some oral mucosal
and dermatological diseases. Its chemical composition and physical properties were studied by standard
and sophisticated methods. Special attention was paid to steranes and hopanes as favorable components
and to aromatics as unfavorable compounds. PY Naphthalan is predominantly composed of saturated aliphatic
hydrocarbons of different structures, and of hydrocarbons comprising aromatic ring(s) (< 15%).
Among aromatics, 98% were monoaromatics and 2% diaromatics, while 16 polycyclic aromatic hydrocarbons
designated by US Environmental Protection Agency as priority pollutants were found at minimum
detectability levels. Steranes and hopanes appeared in native geogenic clusters of homologs and
each of identified compounds was in native geogenic configuration. Steranes were in the range from norcholestanes
up to propyl cholestanes and hopanes up to pentakishomohopanes. The content of steranes
and hopanes was relatively high. Compared to the other naphthalan products, the composition of PY
Naphthalan is remarkably improved. Physical properties make PY Naphthalan convenient for application.
(doi: 10.5562/cca1886
CHARACTERIZATION OF LIQUID CRACKING PRODUCTS USING CHROMATOGRAPHIC METHODS (HPLC, GC)
Sažetak
Proces fluid katalitiÄkog krekiranja (FCC) glavni je konverzijski proces u kojem se teÅ”ke frakcije nafte konvertiraju u lakÅ”e frakcije. TekuÄi produkti katalitiÄkog krekiranja, FCC benzin i lako cikliÄko ulje koriste se za namjeÅ”avanje motornog benzina ili dizelskog goriva. Strogom ekoloÅ”kom i zakonskom regulativom zahtijeva se smanjenje koliÄine sumpora te teÅ”ko izgorivih aromata i olefina u motornim gorivima.
Kromatografskim tehnikama moguÄe je pratiti promjene sadržaja razliÄitih grupa ugljikovodika pri katalitiÄkim reakcijama. U radu je prikazano odreÄivanje grupnog sastava FCC benzina plinskom kromatografijom i sadržaja aromata prema broju aromatskih prstena u FCC benzinima, njihovim frakcijama i lakom cikliÄkom ulju tekuÄinskom kromatografijom. UsporeÄeni su produkti krekiranja iz sirovina razliÄitog porijekla (visoko sumporna i nisko sumporna nafta).Abstract
The process of fluid catalytic cracking (FCC) is the main conversion process in which heavy oil fractions convert into lighter fractions. Liquid catalytic cracking products, FCC gasoline and light cyclic oil, are used for blending motor gasoline or diesel fuel. Stringent environmental and legal regulations require reduction of the content of sulphur and hardly combustible aromatics and olefins in motor fuels. Chromatographic techniques make it possible to monitor changes in the content of various hydrocarbons groups at catalytic reactions. The paper presents the determination of group composition of FCC gasoline through gas chromatography, and that of aromatic content according to the number of aromatic rings in FCC gasolines, their fractions and light cyclic oil, using liquid chromatography. Compared were cracking products obtained from feeds of various origins (high sulphur and low sulphur oil)
TESTING SULPHUR DISTRIBUTION IN LIQUID PRODUCTS OF CRACKED GAS OILS
Sažetak
DanaÅ”nje sirovine za proces fluid katalitiÄkog krekiranja sadrže velike koliÄine ostataka atmosferske i vakuum destilacije koje su bogate sumporom. Produkti nastali katalitiÄkim krekiranjem, prvenstveno FCC benzin i lako cikliÄko ulje, predstavljaju glavne izvore sumpora u motornom benzinu, odnosno dizelskom gorivu. FCC benzin sudjeluje s 35-40 vol %. u motornom benzinu, a pri tom daje 98 % od ukupnog sumpora prisutnog u motornim benzinima. Ove dvije Äinjenice ukazuju na važnost istraživanja raspodjele sumpora u FCC benzinu i drugim produktima katalitiÄkog krekiranja dobivenih iz razliÄitih sirovina.
U radu su usporeÄeni prinosi produkata katalitiÄkog krekiranja plinskih ulja dobivenih iz sirovina koje su sadržavale razliÄite koliÄine sumpora. Ispitivanja su provedena na laboratorijskom ureÄaju za katalitiÄko krekiranje pomoÄu testa mikroaktivnosti (MAT). Dobiveni tekuÄi produkti krekiranja frakcionirani su te je dobivenim frakcijama benzina, lakog cikliÄkog ulja i dekantiranog ulja odreÄen sadržaj sumpora. Frakcijama benzina odreÄen je istraživaÄki oktanski broj (IOB) koji je koreliran sa sastavom i raspodjelom ugljikovodika u benzinu te sa sadržajem sumpora u sirovini, tj. u benzinu.
Dobiveni rezultati pokazuju da koriÅ”tenjem hidroobraÄene sirovine dolazi do poveÄanja konverzije i prinosa FCC benzina, smanjenja IOB FCC benzina i smanjenja sadržaja sumpora u svim tekuÄim produktima krekiranja.Abstract
The present feeds for the fluid catalytic cracking process contain large residual quantities of atmospheric and vacuum distillations that are rich in sulphur. The catalytic cracking products, primarily the FCC gasoline and light cyclic oil, represent the main sources of sulphur in motor gasoline and diesel fuel. The FCC gasoline share is 40 vol.% in motor gasoline, and it provides 98% of the total sulphur quantity contained in motor gasoline. These two facts emphasize the importance of testing sulphur distribution in FCC gasoline and in other products of catalytic cracking obtained from various feeds.
The paper compares the yields of gas oil catalytic cracking products obtained from the feeds containing different quantities of sulphur. Tests have been performed on the laboratory device for catalytic cracking by means of a microactivity test (MAT). The obtained liquid products of cracking are fractionated, so that the resulting fractions of gasoline, light cyclic oil and heavy cyclic oil have a determined sulphur content. The research octane number (RON) has been determined for gasoline fractions, and correlated with the content and distribution of hydrocarbons in gasoline, as well as with the content of sulphur in the feed i.e. gasoline.
The obtained results show that by using hydrotreated feed the conversion and yield of FCC gasoline have increased, while FCC gasoline RON has decreased, as well as the content of sulphur in gasoline and other liquid products of cracking
KOMPLEKSNA EVALUACIJA NAFTA
Na svjetskom naftnom tržiÅ”tu u zadnjih nekoliko godina doÅ”lo je do znaÄajnih promjena koje su utjecale na preispitivanje postupka nabave nafte u naftnim kompanijama. Pravilnim odabirom nafta mogu se znaÄajno smanjiti troÅ”kovi. Odabirom nafta Ina slijedi trendove i kontinuirano se prilagoÄava novim tržiÅ”nim uvjetima. S obzirom na mediteranski položaj Hrvatske i raspoloživi naftovod, Ini su vrlo dostupne nafte iz bivÅ”ih zemalja Sovjetskog Saveza (Rusija, Kazahstan i Azerbajdžan), kao i nafte s Bliskog istoka. Novitet su zapadnoafriÄke nafte, posebice nigerijske, koje su zadnjih godina dostupne i na mediteranskom tržiÅ”tu zahvaljujuÄi smanjenju uvoza nafte u SAD. Zadnjih nekoliko godina Ina pomno odabire nafte i formira naftnu koÅ”aricu koju Äine nafte izabrane s obzirom na dostupnost, cijenu i kvalitetu pogodnu za preradu. Nafte iz naftne koÅ”arice se tehnoloÅ”ki, a potom i ekonomski evaluiraju. Kada izabrana nafta proÄe obje evaluacije, izdaje se odobrenje za preradu. Ako je trenutaÄna cijena evaluirane nafte povoljna, tada se ona kupuje. Naftna koÅ”arica znatno se proÅ”irila te se danas u Ini pored nekoliko standardnih nafta preraÄuju i druge nafte, a trend je joÅ” viÅ”e pratiti promjene na tržiÅ”tu i preraÄivati naftne mjeÅ”avine visoko i niskosumpornih nafta. Kontinuirano se prikupljaju uzorci potencijalnih nafta iz naftne koÅ”arice te se izraÄuju karakterizacije nafte ili naftni eseji (eng. crude oil assay). Podaci se koriste za provedbu tehnoloÅ”ke evaluacije te kao ulazni podaci u softver pomoÄu kojeg se simulira rafinerijska prerada. U radu Äe biti opisan postupak tehnoloÅ”ke evaluacije i prikazan sluÄaj evaluacije nigerijske nafte Bonga koja se od ove godine pored joÅ” jedne nigerijske nafte preraÄuje u INI
USPOREDBA AZERI LIGHT, REB I DOMAÄE SIROVE NAFTE
NaÄinjena je analiza nafti koje se preraÄuju u RN Sisak. Nafte su usporeÄene na osnovi fizikalno-kemijskih svojstava, kao i podataka dobivenih iz destilacijske krivulje, materijalne bilance i prinosa pojedinih frakcija. Dobiveni podaci predstavljaju ulazne podatke za raÄunalnu bazu āSoftware Crude Managerā i āPIMSā koji se koristi za optimiranje rada jedinica atmosferske i vakuumske destilacije u RN Sisak
SEPARATION AND CHARACTERIZATION OF AROMATIC FRACTIONS FROM FCC FEED AND PRODUCTS
Sažetak
FCC proces ili fluid katalitiÄki kreking jedan je od glavnih rafinerijskih procesa, u kojem se konvertiraju teÅ”ka plinska ulja u mnogo vrjednije produkte poput FCC benzina. Da bi se udovoljilo strogim ekoloÅ”kim zahtjevima koje propisuju meÄunarodne specifikacije, potrebno je u motornim gorivima, Äija je komponenta i FCC benzin, smanjiti koliÄinu sumpora, aromata i olefina.
Porijeklo i tip sirovine koja se koristi pri katalitiÄkom krekiranju utjeÄu na raspodjelu i koliÄinu aromatskih ugljikovodika u nastalim produktima. Kromatografskim tehnikama kao Å”to su tekuÄinska kromatografija i vezana tehnika GC/MS moguÄe je pratiti kemizam nastajanja i transformacije razliÄitih aromatskih spojeva iz FCC sirovine u nastale produkte krekiranja kao Å”to su FCC benzin i lako cikliÄko ulje (LCU).
Iz dvije FCC sirovine dobivene iz nafti razliÄitog porijekla razdvojeni su asfalteni od maltena. Iz frakcije maltena odvojene su frakcije zasiÄenih, aromatskih i polarnih ugljikovodika na polupreparativnoj koloni metodom tekuÄinske kromatografije. Frakcija aromatskih ugljikovodika odvojena je na mono, di, tri+ aromate koji su kvantitativno odreÄeni analitiÄkom tekuÄinskom kromatografijom te analizirani vezanim sustavom GC/MS kako bi se i kvalitativno odredili. Produkti katalitiÄkog krekiranja dobiveni iz FCC sirovina FCC benzin i lako cikliÄko ulje takoÄer su analizirani navedenim tehnikama te su usporeÄeni dobiveni rezultati.Abstract
FCC process is one among major refinery processes, converting heavy gas oils into much more valuable products, such as FCC gasoline. In order to meet stringent environmental requirements prescribed by international specifications, it is necessary to reduce motor fuel ā its component being also FCC gasoline - sulphur, aromatics and olefins content.
The origin and type of feed used for catalytic cracking impacts the distribution and volume of aromatic hydrocarbons in generated products.
Chromatographic techniques, such as liquid chromatography and its associated technique of GC/MS, makes it possible to follow the chemistry of generation and transformation of different aromatic compounds out of FCC feed into generated cracking products, such as FCC gasoline and light cyclic oil (LCU).
Out of two FCC feeds obtained from different origin crudes, separated were asphaltenes from maltenes. From the fraction of maltenes separated were fractions of saturated, aromatic and polar hydrocarbons on a semi-preparative column using the method of liquid chromatography. Fraction of aromatic hydrocarbons was separated into mono, di, tri+ aromatics, whose volume was determined by analytical liquid chromatography, and analyzed by its associated system GC/MS, in order to determine their properties as well. Products of catalytic cracking obtained from FCC feeds: FCC gasoline and light cyclic oil, were also analyzed by the said techniques, and the obtained results were compared
Karakterizacija domaÄih nafti
U radu su ispitana dva uzorka domaÄe nafte (nafta Slavonija i Moslavina) i uzorak plinskog kondenzata koji se koriste u preradi u RN Sisak. OdreÄene su fizikalno-kemijske karakteristike uzorkovanih nafti, plinskog kondenzata i njihovih frakcija te je naÄinjena atmosferska i vakuumska destilacija pri Äemu su koriÅ”tene ASTM D 2892 i ASTM D 5236 metode.
Dobiveni podaci predstavljaju fizikalno kemijsku evaluaciju nafti u laboratorijskim uvjetima (ispitani su: destilacijska krivulja, sadržaj sumpora, fizikalno kemijska svojstva frakcija, oktanski broj benzinskih frakcija, ā¦) koji su sastavni dio baze podataka o naftama (eng. crude oil assay). Navedeni podaci korisni su za optimalno voÄenje procesa atmosferske destilacije i vakuum destilacije u RN Sisak, za izbor tehnoloÅ”kog modela rada u rafineriji, odnosno za optimiranje prerade pomoÄu matematiÄkih modela.
UsporeÄene su krivulje destilacije, gustoÄe i sumpora domaÄih nafti i plinskog kondenzata raÄene u razdoblju od 30-ak godina
INFLUENCE OF FCC FEEDSTOCK PRETREATMENT PROCESS ON COMPOSITION AND YIELDS OF LIQUID CRACKING PRODUCTS
Sažetak
Sve stroži zahtjevi vezani uz kvalitetu motornih goriva usmjereni su, izmeÄu ostalog, i na smanjenje koliÄine sumpora u motornim gorivima, Å”to Äe imati znatan utjecaj i na kvalitetu goriva koja Äe proizvoditi domaÄe rafinerije u ovom desetljeÄu.
BuduÄi da su produkti procesa fluid katalitiÄkog krekinga glavne komponente motornih goriva, smanjenje sadržaja sumpora u produktima procesa je od prioritetne važnosti, a najefikasnije se provodi procesima hidroobrade sirovine.
U ovom radu je ispitan utjecaj predobrade FCC sirovine na prinose i sastav produkata, s posebnim naglaskom na koliÄinu sumpora u tekuÄim produktima krekiranja. Predobrada sirovine provedena je na laboratorijskoj aparaturi za ispitivanje procesa hidroobrade, a katalitiÄko krekiranje provedeno je na MAT-sustavu.
Rezultati provedenih eksperimentalnih ispitivanja pokazuju da hidroobrada FCC sirovine utjeÄe na poveÄanje prinosa kreking benzina, odnosno smanjenje prinosa cikliÄkih ulja i koksa, smanjenje sadržaja sumpora u tekuÄim produktima krekiranja te poveÄanje udjela izo-parafina u sastavu kreking benzina.Abstract
Ever more rigorous requirements for the quality of motor fuels are directed additionally towards the reduction of gasoline sulphur content. It is certain that this trends will also have a significant impact on the quality of fuels to be produced by domestic refineries throughout this decade.
Since the products obtained via fluid catalytic cracking are the main components of motor fuels, the removal of sulphur from process products is of extreme priority, and it is provided by feedstock hydrocracking as the most effective method.
The aim of this study is to analyse the influence of FCC feedstock pretreatment on yields and composition of products, as well as the sulphur quantity in liquid cracking products. Feedstock pretreatment was performed in laboratory hydrotreatment process testing equipment, and catalytic cracking on the MAT-system.
The results of experimental testing show that hydrotreatment of FCC feedstock has an influence on increasing of cracking gasoline and lowering the yield of cyclic oil and coke, sulphur content in liquid cracking products and increase of isoparaffin in cracking gasoline compounds