Chng 1Ph gia cho xng

METYL TERT- BUTYL ETE (MTBE)

>Gii thiu chung v MTBE

>Cng ngh v phng php sn xut.

>ng dng

> Thng s k thut.

> Tn cha v bo qun.

Gii thiu chung v sn phm MTBE1 Lch s pht trin MTBE, mc ch ngha. 1.1 S lc v lch s pht trin 1.2 Mc ch ngha 1.3 Tnh cht vt l v ha hc2. Nguyn liu v sn phm.

3. Yu cu v cht lng MTBE thng phm.

1.1 S lc v lch s pht trin

Metyl tert butyl ete (MTBE) l hp cht oxigenat thuc h ete, c tng hp ln uvo nm 1904 bi Williamson. Trong i chin th gii II n c nghin cu nhiu v c bit n nh mt cu t c tr s octan cao. Tuy vy khi nhu cu v ph gia ny cha thc s ln do mi n nm 1970 th nh my cng nghip sn xut MTBE mi c ra i v i vo hot ng ti Italia. Bt u t y n c pht trin trn ton th gii vi nhiu cng ngh mi ra i, c bit khi cc chuyn gia mi trng pht hin ph gia ch gy c hi cho con ngi th ph gia MTBE hon ton thay th.

Williamson, Alexander William

. Metyl tert Butyl ete (MTBE)

Mt s u im ca MTBE Khng cn bt c thay i no i vi ng c hin hnh p sut hi nhin liu gim, do vy gim tn tht bay hi khi bm rt, vn chuynGim kh c hi, c bit l CO v Hydrocacbon cha chyThm 15% MTBE cng khng nh hng n ng c cng nh tng s tiu tn nhin liu, trong iu kin thi tit nhit thp kh nng khi ng ca ng c cng d dng, ngn cn s ng bng tron b ch ha kh.Nhin liu pha trn vi MTBE tng thch vi tt c vt liu s dng sn xut oto nh: m cao su, cc kim loi trong b ch ha kh, bm phun Ngoi nhng u im trn ca MTBE trong s dng lm ph gia cho xng th MTBE cn c nhng ng dng khc trong i sng v trong cng nghip, lm nguyn liu cho qu trnh tng hp hu c, dung mi...Nhc imNhc im ln nht ca MTBE l khi b r r trong qu trnh s dng, tn cha s gy nhim ngun nc, mc d khng gy nh hng n sc khe con ngi nhng MTBE gy ra mi ht sc kh chu cho nc ngay c hm lng rt thp. MTBE d chy v c th to peroxit d n khi tip xc vi khng kh.

1.3 Tnh cht vt l v tnh cht ha hcA. Tnh cht vt l iu kin thng MTBE l cht lng khng mu v linh ng ,c mi tinh du, nht thp, tan t trong nc (1,4%V) nn lng nc ln vo t, kh nng phn chia pha hu nh khng xy ra. MTBE tan v hn trong tt c cc dung mi hu c thng thng v trong tt c cc Hydrocacbon. .Khi lng phn t, MNhit si, tsNhit nng chyHng s in mi (200C) nht (200C)Sc cng b mt (200C)Nhit dung ring (200C)Nhit ha hiNhit hnh thnh (250C)Nhit chyNhit chp chyNhit bc chyGii hn n trong khng kh p sut ti hn, PcrNhit ti hn, Tcr88,1555,3-108,64,50,36202,18337-314-34,88-284601,65 8,43,43224Kg/mol0C0CmPa.smN/mKj/Kg.KKj/KgKj/molMj/Kg0C0C%VMpa0C.MTBE l ph gia c s dng nhiu nht v ph bin nht trong cc ph gia ca Ete. Chng hn M MTBE c pha trn vi 15%V. Vic tng hm lng MTBE trong xng s lm thay i p sut hi bo ha, thnh phn ct phn on nhin liu. Thng thng MTBE c pha vo xng vi t l 5 15%V vi t l ny s tng 2 5 ON cho xng sau pha trn, tng ng vi hm lng ch t 0,1 0,15g/l.

.

B. Tnh cht ha hcMTBE l cht kh n nh trong mi trng kim, trung tnh v a xit yu. Khi c mt ca axit mnh th n b phn hy thnh metanol v iso buten phn ng sau:

.Xc tc: TREVERLYST Nguyn t oxi trong phn t MTBE cn c mt cp in t khng chia v cc gc ankyl c hiu ng dng lm cho MTBE mang tnh ca mt Bazo yu

http://www.chemra.com

. Mt s phn ng ca MTBE

MTBE phn ng vi cc gc axit v c mnh nh: HCl, H2SO4 to mui

Phn ng vi HI

Phn ng vi Oxi nhit cao

HI.

MTBE khng ch l mt cu t c tr s octan cao pha vo xng m bo k thut ca xng thng phm dng cho ng c hin nay m yu cu v nhin liu sch ngy cng cao n lm tng thm ng k khi m ngun nguyn liu ny ang gn cn kit, n gp phn khng nh vo ci thin mi trng v hn ch c lng CO v Hydrocacbon chy khng ht thi ra ngoi.Vic thit k phn xng sn xut MTBE c mt ngha rt quan trng trong tnh hnh hin nay.2.Nguyn liu v sn phm Metanol Iso-Buten.i lng vt liu kinGi trn vT trng, 101,3kPaNhit siNhit nng chyNhit ti hnp sut ti hnNhit dung ring, (250C v 101,3kPa)Nhit ha hi, 101,3kPa nht, 250C

Gii hn n trong khng kh00C250C500CKhLngLngHi0,81000,786640,763764,70-97,68239,498,09744,0681,081138,80,55139,68.1035,5 44g/cm3g/cm3g/cm30C0C0CMPaJ/mol.KJ/mol.KKj/kgMPa.sMpa.s%TTA. Tnh cht vt l metanol Phng php tng hp Metanol

Trong cng nghip metanol c tng hp bng nhiu phng php. Trc y n c iu ch bng cch chng than g. Ngy nay Metanol c tng hp bng mt trong hai phng php sau:Oxi ha trc tip metanT l CH4: O2 = 1: 2 (theo th tch) xc tc l Cu, Fe hoc NiTng hp metanol t kh tng hp

T l CO: H2 = 1: 2 (theo th tch), xc tc l ZnO CrO3. Hiu sut sn phm t trn 90%, tinh khit ca metanol l 99%. Hin nay y l phng php sn xut chnh to Metanol cng nghip

Bng : Tnh cht vt l ca Iso buten

i lng vt liu kinGi trn vNhit siNhit nng chyNhit ti hnp sut ti hnT trng ti hnT trng ca lngT trng ca khNhit ha hi p sut bo haNhit dung ringNhit chyGii hn n vi khng kh101,3Kpa101,3Kpa00C; 101,3Kpa250CT0CKh l tngLng; 101,3Kpa250C, P = const200C; 101,3KPa-6,9-140,34147,54,000,2390,58792,582366,9394,215892336-2702,31,8 8,80C0C0CMPag/cm3g/cm3kg/m3J/gJ/gJ/g.KJ/g.KKj/mol%TTB. Tnh cht ha hc ca iso buten

Phn ng cng:Cng ru to ete

Cng nc to TBA

Cng Hydro halogenua (HX)

Phn ng oxy ha

Phn ng cng polymer ha

21Cc ngun iso buten hin nay

Iso buten ly t ngun rafinat 1 :l hn hp kh thu c t xng sn xut etylen bng qu trnh cracking hi nc . u im l nng iso buten tng i cao (khong 44% v c th s dng trc tip sn xut MTBE.) Iso buten t phn on C4 ca qu trnh xc tc tng si (FCC BB). So vi phn on C4 ca Crking hi nc th nng iso buten ln hn nhiu. Tuy nhin vn u t v gi thnh sn xut s cao hn khi dng ngun cracking hi nc.Iso buten t qu trnh Hydrat ha Tert butyl alcol (TBA), trong TBA thu c t ng sn phm ca qu trnh tng hp propylene hi oxit.Iso buten t qu trnh hydro ha iso butan : trong iso butan c th nhn c t qu trnh lc du hoc t qu trnh isome ha kh m n-butan. y l ngun nguyn liu s p ng c nhu cu MTBE v l hng pht trin c trin vng. Mc d u t cho sn xut i hi cao hn:Tnh hnh sn xut v tiu th ph gia MTBE

MTBE l cu t c tr s octan cao c s dng ph bin nht hin nay lm ph gia pha xng nng cao tr s octan. MTBE,l hp cht c tr s octan cao, tan hon ton trong xng, phn b u trong ton b th tch ca xng, c bit cn l nhng hp cht kh an ton cho ngi s dng. Hin nay cc nh ch to ng c khng ngng ci tin cng ngh cho ra i cc ng c c cng sut ln, t s nn cao. Nhng ng c ny i hi nhin liu ca chng phi c cht lng cao, nhin liu chy trong ng c phi m bo khng b chy kch n, ng thi m bo t cng sut thit k, bn cho ng c v khng hao tn nhin liu.

3. Yu cu v cht lng MTBE thng phm

Do tnh cht ca sn phm ch yu lm ph gia nhu cu v tinh khit ca MTBE l 98,4 99 % Wt, cn li 1 2% bao gm cc sn phm ph nh tert butanol v di isobuten, metanol d l nhng cu t khng nh hng n tr s octan ca MTBE trong xng do vy khng cn loi b mt cch kht khe.

Bng 1: Thnh phn ca MTBE thng phm

MTBE98 99%WtAlcol (CH3OH, tert butanol) 0,5 1,5 %WtCc Hydrocacbon (C5 v C6) 0,1 1%WtNc 50 150ppmTng sunfuaMax 10ppmCht d tha trong h bay hiMax 10ppm

.Hin nay, cc cng ngh sn xut MTBE c lp t trn nhiu ni trn th gii vi tng cng sut ln khoang 2.275 nghn tn/ nm. Cc xng ny c lp t, s dng cng ngh ca cc hng khc nhau. Cng ngh ca hng Snamprogetti M s dng nguyn liu FCC BB v thit b on nhit Cng ngh ca Hills AG cng c p dng nhiu trong cc xng ca CHLB c. Nhng cng ngh gn y nh cng ngh ARCO ca Texaco ang c p dng cc nc M v Ty u. Cng ngh ca CD Tech (ABB lummus) cng c s dng vi hn 60 xng v gn 30 d n. Cng ngh sn xut MTBE ca UOP vi 11 xng c cng xut 30000 thng/ ngy, s dng nguyn liu l kh butan c sn t m kh. Hn 26 xng sn xut da trn cng ngh ca hng IFP, 7 xng sn xut trn cng ngh ca hng Philip, cng ngh ca hng Shell ang c xy dng v hot ng khp mi ni. Gn y Arap xeut, Venezuela v cc vng khc ngi ta cng xy dng cc xng sn xut MTBE t nguyn liu l kh Butan t m kh s dng cng ngh ca hng UOP.

Phn 2 : Cng ngh v phng php sn xut MTBE2.1 C s ca qu trnh : Phng trnh :

ng hc qu trnh: + L 1 phn ng thun nghch + L 1 phn ng to nhit nh + C ch ca phn ng :

+ Xc tc ca qu trnh : - Dng d th lng rn nn duy tr c qu trnh th thng phi tin hnh P cao duy tr nguyn liu tn ti trng thi lng. ( P = 20 at, T0 s metanol = 166.5 0 C , iso buten l 105.2 0 C )

- Xc tc thng l cc axit rn . Nh c 2 loi thng c dng trc kia : > Xc tc polyme ng trng hp c nhm SO3 H> Xc tc nha trao i ion c tnh axit ( do nhm SO3 quyt nh) v c l mao qun ln.

- Ngy nay, khoa hc pht trin cc nh khoa hc tm ra nhiu loi xc tc mi c nhiu u im, cho nng xut cao hn ng thi theo phng php ny th th qu trnh polyme ho v dime ho Iso-buten lm chn lc ca MTBE gim ng k. Nhng i mi gn y a ra xc tc zeolit c chn lc cao hn.

- c tnh ca xc tc zeolit Tnh hot ng cao. chn lc cao. S n nh v thi gian lm vic cao. Khng mt i kim loi hot ng. Khng c cc bn trong v bn ngoi mao qun. Khng to ra cc phn ng ph. Khng c s kt t ca nhng kim loi hot ng. Khng c nhng phn ng cracking. Hn ch s khuych tn ti thiu.

Cc yu t nh hng n qu trnh:+ To nhit nh : thng thc hin nhit thp . Nhng nhit qu thp lm chm tc phn ng.

+ Thun nghch: phi cho d cht phn ng. Nhng iso buten d b dyme ho , polyme ho. Do t l lng cht phn ng iso buten v metanol phi iu chnh ph hp trnh cc phn ng ph.

+ Xc tc: c ch l trao i ion do hot tnh ca xc tc cng tt th hiu qu ca qu trnh cng tt . Ngoi ra, hnh dng v kch thc mao qun cng gi vai tr quan trng trong vic khng ch phn ng ph.+ S c mt ca nc : lng va th c th lm tng hiu sut to ion. Nhng lng ln c phn ng ph xy ra.Cc ngun iso buten hin nay :

Iso buten ly t xng sn xut etylen bng qu trnh cracking hi nc. u im l nng iso buten tng i cao (khong 44% v c th s dng trc tip sn xut MTBE.) Iso buten t phn on C4 ca qu trnh xc tc tng si (FCC). So vi phn on C4 ca Crking hi nc th nng iso buten ln hn nhiu. Tuy nhin vn u t v gi thnh sn xut s cao hn khi dng ngun cracking hi nc.Iso buten t qu trnh Hydrat ha Tert butyl alcol (TBA), trong TBA thu c t ng sn phm ca qu trnh tng hp propylene hi oxit.

Iso buten t qu trnh hydro ha iso butan : trong iso butan c th nhn c t qu trnh lc du hoc t qu trnh isome ha kh m n-butan. Cc ngun Metanol hin nay :

Ngy nay Metanol c tng hp bng mt trong hai phng php sau:Oxi ha trc tip metan : T l CH4: O2 = 1: 2 (theo th tch) xc tc l Cu, Fe hoc NiTng hp metanol t kh tng hp : T l CO: H2 = 1: 2 (theo th tch), xc tc l ZnO CrO3. Hiu sut sn phm t trn 90%, tinh khit ca metanol l 99%.2.2 Chn nguyn liu : + isobuten t hydro ho TBA. TBA l sn phm ca qt propylenoxit >> ko thun li do phi c kt hp vi phn xng khc.+ Isobuten t FCC hoc Steam Cracking th ngun nguyn liu b hn ch do lng iso buten cha trong phn on C4 thp. Ch s dng quy m nh.+ Iso buten ngy nay thng c sn xut t m butan. Nguyn liu di do. D yu cu phi tn km hn v mt kinh t.==>Cng ngh chung ca sn xut MTBE t hn hp C4 (t n-butan) qua 3 giai on chnh l :ISOME ha n-butan thnh Iso-butanDehydro ha Iso-butan thnh Iso-butenTng hp MTBE t Iso-buten v Metanol.

UOP Ether ComFlexField butanes, a mixture of normal butane and isobutane obtained from natural gas condensate, are fed to a deisobutanizer (DIB) column. The DIB column prepares an isobutane overhead product, rejects any pentane or heavier material in the DIB bottoms, and makes a normal butane sidecut for feed to the paraffin isomerization unit. The DIB overhead is directed to the Oleflex unit. The once-through conversion of isobutane is approximately 50 percent. About 91 percent of the isobutane conversion reactions are selective to isobutylene and hydrogen. On a mass basis, the isobutylene selectivity is 88 wt %. Two product streams are created within the C4 Oleflex unit: a hydrogen-rich vapor product and a liquid product rich in isobutane and isobutylene.The C4 Oleflex liquid product is sent to an etherification unit, where methanol reacts with isobutylene to make MTBE. Isobutylene conversion is greater than 99 percent, and the MTBE selectivity is greater than 99.5 percent. Raffinate from the etherification unit is depropanized to remove propane and lighter material. The depropanizer bottoms are then dried, saturated, and returned to the DIB column.

37

S qu trnh sn xut MTBE t kh n-butan nh sau:

2.3 Phng php sn xut t n butan: 2.3.1. Isome ho n_butan:Isome ho l qu trnh iu ch nguyn liu cho qu trnh dehydro ho bng xc tc chuyn ho n-Butan thnh Iso-butan phn ng xy ra nhit 300-400 0F v p sut 200-500 psi. Qu trnh Isome ho s dng xc tc AlCl3uimcaloixctcnylhottnhrtcao,nhit930Chunhchuynhahontonccparafin.Nhcimcaloixctcnylmaumthottnh,chnlc thpvdbphnhu.axitmnhcaxctcdgynmnthitb

Vi xc tc ny c cng ngh UOP

1: Thp tch 2, 9: Thit b lng 3, 4: L phn ng 5, 6: Thit b sy, 7: Thit b lng 8: Thit b chng tch 10: Thp ra, I: nguyn liu Butan II: Iso Butan III: Nhin liu kh IV: Kim thi. The aim of catalyst development throughout history was to obtain a high activity catalyst which could be practically implemented. In the 1960s, early aluminum chloride catalysts were plagued with high corrosivity, high consumption and high processing costs7. The main advantage, however, was the low operating temperatures (< 200aC) due to the high acidity. Catalysts which incorporated platinum on an acid support of Al2O3 were later developed, but were less active and required harsh operating temperatures (~320-450aC).The third generation of catalysts consists of chlorinated alumina combined with platinum and is predominantly used in industry today. Similar catalysts are commonly used in the isomerization of other light alkanes (C5/C6), suggesting the catalysts is not highly sensitive to the carbon number in the feed; provided adequate nC4 amounts are present in the feed. Examples of this type of catalysts are the commercially available I-12 and I-20 catalysts readily used in UOPs Butamer process.The balance between the acidic and metallic sites plays a role significant role in the performance of the process. It implicitly determines the probability of acid catalyzed side-reactions taking place by determining the alkene partial pressure6. Production of the catalyst is performed by treating the platinum alumina matrix with carbon tetrachloride at high temperatures without affecting the pore structures. It is crucial to control acidity so as not to favour undesired hydrocracking reactions. As well, the amount of platinum will depend on the molecular mass of the feed- heavier feeds are more likely to have coke formation. The alumina 10 matrix will consist of about 8-15 wt% Cl2 and 0.3-0.5 wt% Pt8. Continuous injection of a chlorination agent maintains the high acidity and allows for lower operating temperatures.The advantage of a bifunctional catalyst is the opportunity for stable isomerization under adequately high hydrogen pressure. From the chain termination reactions, formation of the unwanted, unsaturated molecules can be reduced by ensuring alkene intermediates are kept saturated with hydrogen. In addition, the presence of platinum prevents coke deposition.The catalyst is highly sensitive to poisons and pre-purification of the feed is a necessity. The catalyst is especially susceptible to water. Molecular sieve drying systems are effectively used to remove any water present in the hydrocarbon or hydrogen feeds. Other heteroatoms, such as sulphur, must also be removed before being fed into the hydroisomerization unit. Typical processes would involve various hydrotreating reactions (HDN, HDS, HDO) and caustic extraction to remove sulphur contents. Fluoride which may be introduced from coupling with an alkylation unit will degrade the catalyst and can be removed by passing the feed over a hot bed of alumina. The molecular sieves may also have the capacity to remove heteroatoms.The main disadvantage of the catalysis is hydrogen chloride (HCl) formation directly caused by a combination of the hydrogen pressure and continued injection of chloride. Elution of chlorine from the catalysts will affect all downstream components due to the highly corrosive nature of HCl. A caustic scrubber is necessary to neutralize any HCl present in the off-gas.39

Mt khc xc tc dng cho qu trnh isome ho c th dng Pt hoc Al2O3 hay Pt/Al2O3 c tm mt lng hp cht hu c dn xut Clo. Kh n-butan a vo s chuyn thnh iso-butan gn im cn bng.

C ch ca qu trnh:

Basic Process Flow Diagram for the UOP HOT Butamer

S cng ngh :

1 : Thp tch Iso-Butan 2 : Thp sy 3, 4: L phn ng 5: Thit b chng tch 6: Thp n nh 7: Thp ra kh 8: My nn I : Nguyn liu n-Butan, II: C5+ v Hydrocacbon III: Sn phm Iso-butan, IV: Kh nhin liu, V: Na2CO3 s dng.

2.3.2. Qu trnh dehydro ho iso butan thnh iso buten:

Xc tc Pt/Al2O3 ( khong 2%) trong qu trnh ny thc hin song song qu trnh hydro ho (thit b tng si) v ti sinh xc tc lin tc.Cng ngh Oleflex (UOP) c nhng c im sau+ chn lc ca qu trnh cao+ Qu trnh lm vic lin tc v c th c gii ha t ng ha d dng+ Nng xut ca thit b rt ln+ bn c bn nhit ca xc tc cao, vn chuyn xc tc d dng+ Sn phm ph c tn dng trit + Xc tc lu mt hot tnh, hot tnh ca xc tc gim chm do m bo c chuyn ha cao.Tuy nhin cng ngh ny c nhc im:+ Tiu hao nhit nng lng rt ln+ Xc tc Pt t tin, d b ng c lu hunh+ S lng thit b nhiu do i hi din tch xy dng ln.+ Mc an ton chy n phi m bo mt cch nghim ngt

Cng ngh ca oflex

1: Thit b phn ng, 2: Thit b t nng (gia nhit)3: L ti sinh xc tc4: Thp sy 5: Tuabin gin n kh, 6: Thp tch hydro, 7: Thp ct phn sn phm nh. I: nguyn liu Iso-butan k thut v Iso-butan tun hon II: Kh thi III: Sn phm Iso-buten IV: Phn ct sn phm nh V: Hydro tun hon

Field butanes, a mixture of normal butane and isobutane obtained from natural gas condensate, are fed to a deisobutanizer (DIB) column. The DIB column prepares an isobutane overhead product, rejects any pentane or heavier material in the DIB bottoms, and makes a normal butane sidecut for feed to the paraffin isomerization unit. The DIB overhead is directed to the Oleflex unit. The once-through conversion of isobutane is approximately 50 percent. About 91 percent of the isobutane conversion reactions are selective to isobutylene and hydrogen. On a mass basis, the isobutylene selectivity is 88 wt %. Two product streams are created within the C4 Oleflex unit: a hydrogen-rich vapor product and a liquid product rich in isobutane and isobutylene.The C4 Oleflex liquid product is sent to an etherification unit, where methanol reacts with isobutylene to make MTBE. Isobutylene conversion is greater than 99 percent, and the MTBE selectivity is greater than 99.5 percent. Raffinate from the etherification unit is depropanized to remove propane and lighter material. The depropanizer bottoms are then dried, saturated, and returned to the DIB column.44

3. Thng cha dng kh nn vn chuyn 4. Thng tch 5. Thp ti sinh 6. B phn iu chnh dng 7. Thng trung gian 8. Thng cha bi 9. Bm kh nngKh nng xc tcII. Dng Hydro lm kh nng III. Dng Nit lm kh nng IV. Kh ti sinh V. Kh thi ti sinhThe regeneration section, shown in Fig. 5.1.2, is similar to the CCR* unit used in theUOP Platforming* process. The CCR unit performs four functions: Burns the coke off the catalyst Redistributes the platinum Removes the excess moisture Reduces the catalyst prior to returning to the reactorsThe slowly moving bed of catalyst circulates in a loop through the reactors and the regenerator. The cycle time around the loop can be adjusted within broad limits but is typically anywhere from 5 to 10 days, depending on the severity of the Oleflex operation and the need for regeneration. The regeneration section can be stored for a time without interrupting the catalytic dehydrogenation process in the reactor and recovery sections.45

2.3.3. Qu trnh ether ho to MTBE :Qa trnh ny c tin hnh nhit 40-90 0C v p sut 7-20 atm, xc tc dng l nha trao i ion, phn ng thc hin trong pha lng. Cng ngh qu trnh Ether ho ca mt s hng nh: Qu trnh CD TECH (Lummus), Ethermax (UOP), Philips Etherfication Proces (Philip).

Hai cng ngh CD TECH v Hills hin nay vn c ang s dng nhiu nhm sn xut MTBE vi chn lc cao 99,5 100% c bit i vi cng ngh Hills 2 giai on cho chuyn ha gn nh 100%.. Do hiu sut ca qu trnh s gim xung nn hiu sut cao th thng dng cng ngh Ethermax( UOP)

S cng ngh Ethermax ca UOP

reaction with distillation48MTBE c mt nh ln trong thp k qua khi n xy ra bi phn ng Ngoi ra n gin ca isobutylen vi methanol trong s hin din ca cht hot ho acid (nha), v s dng chnh ca n l tng ch s octan ca xng v nhu cu ny tng ng k.Qu trnh ny c xut nh mt s mi l Ethermax cng ngh UOP qu trnh s dng mt l phn ng c nh, theo sau l mt thp chng ct xc tc phc v l phn ng th 2, v lm sch sn phm cui cng.IV. ng dng1. Lm ph gia tng tr s octan cho xng Trc khi s dng MTBE lm ph gia tng tr s octan ca xng, hay tng kh nng chng kch n, th gii tng s dng ph gia ch ( ch tetra-ethyl ). Tuy nhin, ph gia ch gy hi n sc khe ca con ngi v mi trng. V th, vo nm 1986 nc M cm s dng ph gia ny, Chu u vo nm 1990, cn nc ta vo 11/2001 cng cm s dng. Thay vo , hin nay th gii ang s dng MTBE thay th ch tetra-ethyl

50MTBE vi cc u im sau:Tr s octan ca xng pha MTBE khong 115-125 i vi RON v 92 - 120 i vi MON.- Khng i hi phi thay i cc b phn ca xe.- Khng n mn cc thit b ca ng c. - Cng sut ng c v lng nhin liu tiu th khng thay i, khong lng MTBE pha vo xng khong 15% th tch- Khng thi cc cht c hi nh hp cht ca ch,hydrocacbon thm...- Ct gim kh thi c bit l CO2, hydrocarbon khng chy, cc hydrocacbon thm, v bi cacbon.- t nh hng n sc khe v mi trng hn so vi ph gia ch.Hn 95 % ca MTBE sn xut c s dng trong xng2. Tch isobuten khi phn on C4 Methyltert -butyl ether cng c s dng trong ngnh cng nghip ho du, l hp cht trung gian quan trng. Tch isobutene bng MTBE l ng dng duy nht c c s dng trn quy m cng nghip v thu c olefin c tinh khit cao. Qa trnh tch gm 2 giai on: Tng hp v tinh ch MTBE Cracking MTBE v tinh ch isobuten to thnh. chuyn ha cao 95-98%, chn lc t 99,9% i vi isobuten v 94% i vi metanol.Do , khng cn phi tun hon MTBE chua phn ng.

V. Thng s k thut cht lng v phn tch ha hc 1. Thng s k thut cht lng ca MTBE tinh khit thng mi ca MTBE thng thng l 98 99 wt%. Cc sn phm ph nh tert- butanol v diisobutenes, v Methanol d, khng c nh hng bt li v ci thin ch s octan thng qua MTBE s dng .Ty thuc vo cht lng ca cc nguyn liu C4 hn hp , cc sn phm MTBE cng c th chaC5 v C6 hydrocarbon. Thnh phn ca MTBE thng s dng trong lnh vc nhin liu c a ra di y:MTBE 98 99 %Ru, cn ( methanol ,tert- butanol ) 0,5 - 1.5wt %Hydrocarbon ( C5, C6 - hydrocarbon , diisobutenes ) 0.1 - 1.0wt %Nc 50-1500 ppm theo trng lngTng lng lu hunh 10 ppm theo trng lng.

2. Phn tch ha hc MTBE c phn tch bng sc k kh ,tt nht l ct mao mch vi mt pha tnh phn cc cao . V d : TCEP [ 1,2,3 - tris -(2- cyanoethoxy ) propan ] , Carbowax 20M , hoc DX -1. Pha tnh l pha rn, ch yu l hp cht ca silic v nhm oxit.

VI. Tn cha v vn chuyn MTBE l cht khng gy n mn, nn tn cha,bo qun,phn phi c th dng cc thit b ging nh cha cc nhin liu lng khc. L mt ete nn MTBE c th lu tr trong thi gian di ngay trong s c mt ca khng kh. Cn phi lu tr kh, bi v nc l c th trn vi MTBE gy phn lp nhin liu v nh hng n cht lng ca nhin liu. Sn phm c th c lu tr trong thit b khng cn p sut cao, v vt liu lm bn cha c th dng thp cacbon. Methyltert -butyl ether c p sut hi 61 kPa 40 C, nhit chp chy thp -28 C, nhit bt chay 460 C. Do , cn c cc bin php phng nga an ton chy n cho cht lng d chy. Vn chuyn MTBE ging nh cc nhin liu lng nh xng,diesel,...

Xe vn chuynBn chaVII. Vn nhim mi trng v sc khe con ngi MTBE nh hng n mi trng ch yu l do mt lng MTBE trong sn xut v bo qun,vn chuyn b tn tht ra mi trng. Thm vo mch nc ngm gy nhim mi trng nc. C quan bo v mi trng Hoa K (EPA) cho bit: nu cc mc nhim di 20-40 phn t (ppb) th c xem nh khng c, tuy nhin l nc c cha cc c t mc thp hn th mi ca nc vn b hi.. Tuy nhin, vn ny c th khp phc bng cc bin php k thut nh s dng cc bn cha,vn chuyn hin i, s dng titan oxit chuyn ha MTBE thnh CO2.... C quan Bo v Mi trng Hoa K (EPA) kt lun rng d liu sn c khng nh lng ri ro sc khe ca MTBE cc cp tip xc thp trong nc ung, nhng d kin h tr kt lun rng MTBE l mt cht gy ung th tim nng liu cao. MTBE b cm cc bang California v New York Hoa K, bt u t 1 thng 1 nm 2004. Tnh n thng 9 nm 2005, hai mi lm quc gia k lut cm MTBE.Do , cn gim tip xc v trang b cc bo h...cho ngi lao ng.