Mono ethylene glycol (MEG, Ethylene Glycol, EG) yog kev lag luam tsim los ntawm ob txoj kev tseem ceeb: ethylene oxide (EO) hydration (lub ntiaj teb mainstream) thiab thee-rau-MEG (DMO) (Tuam Tshoj txoj kev xaiv loj).
Tshaj li 90% ntawm MEG thoob ntiaj teb tso tawm los ntawm EO hydration txheej txheem, thaum thee-raws li DMO thev naus laus zis suav nrog ntau dua 40% ntawm Tuam Tshoj lub peev xwm tag nrho.
mono ethylene glycol manufacturing txheej txheem
1. Mainstream Route: Ethylene Oxide (EO) Hydration
Txoj kev EO hydration yog cov txheej txheem thoob ntiaj teb rau MEG ntau lawm.
Nws pib los ntawm ethylene (los ntawm naphtha, ethane, los yog MTO) thiab hloov mus rau ethylene oxide (EO), ces mus rau MEG ntawm hydration.
Kauj Ruam 1: Ethylene Oxidation rau EO
Ethylene (C₂H₄) reacts nrog oxygen tshaj ib cov nyiaj -raws li catalyst.
Cov tshuaj tiv thaiv yog 150-240℃thiab 1.5-2.0 MPa.
Kev hloov pauv ib zaug yog 10-15%, thiab EO xaiv yog 80-85%.
Cov khoom lag luam muaj xws li CO₂, dej, thiab kab aldehydes.
Kauj ruam 2: EO Hydration rau Crude MEG
EO hloov mus rau MEG los ntawm cov tshuaj tiv thaiv dej.
Ob txoj kev lag luam yog siv:
A. Ib txwm tsis yog-Catalytic Hydration (Cov Qauv Thoob Ntiaj Teb)
Cov xwm txheej yog 150-200℃thiab 2.0-2.5 MPa.
Dej-rau-EO piv yog 22–25: 1 (molar).
Mono Ethylene Glycol (cas 107-21-1) xaiv yog 89-92%.
Cov khoom tseem ceeb yog MEG, thaum DEG thiab TEG account rau txog 10-12% byproducts.
Cov zis yog 13-15% MEG aqueous tov.
B. Catalytic Hydration (Lub zog-Txuag txheej txheem)
Cov txheej txheem no siv ion- pauv resin lossis txhawb ammonium ntsev catalysts.
Cov xwm txheej yog 80-110℃thiab 1.0-1.5 MPa.
Dej-rau-EO piv yog txo rau 1–6: 1.
Kev hloov pauv EO ntau dua lossis sib npaug rau 97%, thiab MEG xaiv yog 94-98%.
Chav noj yog txo los ntawm kwv yees li 20% piv nrog cov uas tsis yog -catalytic txoj kev.
Kauj Ruam 3: Purification & Refining
Crude mono ethylene glycol meg yog concentrated los ntawm 3-6 nyhuv evaporation.
Dej raug tshem tawm mus rau kwv yees li 85% MEG concentration.
Thaum kawg purification siv lub tshuab nqus tsev distillation ntawm 10-20 kPa hauv ntau kab.
Cov khoom purity kawg yog ntau dua lossis sib npaug rau 99.9% (fiber / qib kev lag luam MEG).
Cov khoom lag luam muaj xws li DEG (~ 10%), TEG (~ 1%), thiab polyglycols (residue).
2. Tuam Tshoj Txoj Kev Xaiv: Coal-rau-MEG (DMO Txoj Kev)
Txoj kev thee-rau-MEG txoj kev yog syngas- cov txheej txheem tsim nyob rau hauv Suav teb.
Nws yog dav siv los ntawm Tuam Tshoj tus "nplua nuj thee, roj tsis zoo" cov qauv tsim.
Kauj ruam 1: Coal Gasification rau Syngas
Coal yog hloov mus rau hauv cov roj synthesis (CO + H₂).
Cov syngas yog purified rau ntau dua los yog sib npaug rau 99% CO.
Kauj Ruam 2: Carbonylation rau Dimethyl Oxalate (DMO)
CO reacts nrog methyl nitrite (MN) tshaj palladium catalyst.
Qhov no tsim dimethyl oxalate (DMO, C₄H₆O₄).
NOx yog rov siv dua los tsim methyl nitrite.
Kauj ruam 3: DMO Hydrogenation rau Crude MEG
DMO yog hydrogenated rau MEG siv tooj liab -raws li catalyst.
Cov tshuaj tiv thaiv yog 180-220℃thiab 2.5-3.0 MPa.
Cov khoom muaj xws li MEG thiab methanol, thiab methanol yog siv dua.
Kauj Ruam 4: Distillation
Cov txheej txheem purification yog tib yam li txoj kev EO.
Thaum kawg mono ethylene glycol (cas tsis yog 107-21-1) purity ncav cuag ntau dua los yog sib npaug rau 99.9%.
3. Emerging Green Route: CO₂-Based EO/MEG
Cov txheej txheem kev lag luam tshiab siv CO₂ kev koom ua ke thev naus laus zis.
Ib qho piv txwv yog EO reacting nrog CO₂ los ua ethylene carbonate (EC), uas tom qab ntawd hloov mus rau MEG.
Kev hloov pauv EO yog kwv yees li 100%.
Mono ethylene glycol meg xaiv tau ntau dua lossis sib npaug li 99%.
Cov txiaj ntsig suav nrog 30% cov dej khib nyiab tsawg dua thiab 15% qis carbon emissions.
Cov ntaub ntawv tseem ceeb ntau lawm & sib piv
| Parameter | EO Tsis-Catalytic | EO Catalytic | Coal-to-MEG (DMO) |
|---|---|---|---|
| Dej: EO piv | 22–25:1 | 1–6:1 | N/A |
| MEG selectivity | 89–92% | 94–98% | 90–93% |
| Kev siv zog | High (siab dej piv) | -20% yog ' | Nruab nrab |
| Cov khoom noj | Naphtha/ethane | Naphtha/ethane | Coal/syngas |
| Ntiaj teb no qhia | ~70% | ~20% | ~10% |
Xaus
Kev lag luam MEG raug tswj hwm los ntawm EO hydration (siab loj hlob, loj teev), thaum thee-to-MEG (DMO) yog Tuam Tshoj tus nqi-zoo lwm txoj. Catalytic hydration thiab CO₂-raws li txoj kev tau txais traction rau qis zog siv thiab emissions. Cov khoom kawg MEG tsis tu ncua ua tau zoo dua lossis sib npaug rau 99.9% purity raupolyester, antifreeze, thiab industrial siv.