Qhov feem pua ntawm cov roj cav
Txheem
Kev faib tawm roj
Raws li cov txheej txheem ntawm tau txais cov roj rau sab hauv combustion engine, lawv muab faib ua 3 pawg:
- Mineral (petroleum)
Tau los ntawm kev ncaj qha roj refining ua raws li kev sib cais ntawm alkanes. Xws li cov khoom muaj txog li 90% branched saturated hydrocarbons. Nws yog tus cwj pwm los ntawm kev sib cais siab ntawm paraffins (heterogeneity ntawm molecular luj ntawm chains). Raws li qhov tshwm sim: lub roj nplua nyeem yog thermally tsis ruaj khov thiab tsis khaws viscosity thaum ua haujlwm.
- Khoom cua
Cov khoom ntawm petrochemical synthesis. Cov khoom siv raw yog ethylene, los ntawm qhov uas, los ntawm catalytic polymerization, lub hauv paus nrog qhov hnyav molecular thiab ntev polymer chains tau txais. Nws tseem tuaj yeem tau txais cov roj hluavtaws los ntawm hydrocracking mineral analogues. Qhov sib txawv ntawm kev ua haujlwm tsis sib xws hauv lub neej ua haujlwm.
- Semi-synthetic
Taw qhia txog kev sib xyaw ntawm cov ntxhia (70-75%) thiab cov roj hluavtaws (txog 30%).
Ntxiv nrog rau cov roj hauv paus, cov khoom tiav suav nrog ib pob ntawm cov khoom ntxiv uas kho cov viscosity, detergent, dispersant thiab lwm yam khoom ntawm cov kua.
Kev sib xyaw ua ke ntawm lubricating lub cev muaj zog yog nthuav tawm hauv cov lus hauv qab no:
| Cheebtsam | Feem pua |
| Base (saturated paraffins, polyalkylnaphthalenes, polyalphaolefins, linear alkylbenzenes, thiab esters) |
~ 90% |
| Ntxiv pob (viscosity stabilizers, tiv thaiv thiab antioxidant additives) | Nce txog 10% |
Cav roj muaj pes tsawg leeg nyob rau hauv feem pua
Cov ntsiab lus hauv paus ncav cuag 90%. Los ntawm cov tshuaj lom neeg, cov pab pawg hauv qab no tuaj yeem paub qhov txawv:
- Hydrocarbons (limited alkenes thiab unsaturated aromatic polymers).
- Complex ethers.
- Polyorganosiloxanes.
- Polyisoparaffins (spatial isomers ntawm alkenes hauv daim ntawv polymer).
- Halogenated polymers.
Cov pab pawg zoo sib xws ua rau 90% los ntawm qhov hnyav ntawm cov khoom tiav thiab muab lubricating, detergent thiab tu zoo. Txawm li cas los xij, cov khoom ntawm roj av lubricants tsis ua raws li qhov yuav tsum tau ua ntawm kev ua haujlwm. Yog li, saturated paraffins ntawm qhov kub thiab txias tsim coke deposits ntawm lub cav. Esters tau txais hydrolysis los tsim cov kua qaub, uas ua rau corrosion. Txhawm rau tshem tawm cov teebmeem no, cov kev hloov kho tshwj xeeb tau qhia.
Additive pob - muaj pes tsawg leeg thiab cov ntsiab lus
Qhov sib faib ntawm modifiers hauv cov roj cav yog 10%. Muaj ntau yam npaj ua "cov pob khoom ntxiv" uas suav nrog cov txheej txheem kom nce qhov yuav tsum tau ua ntawm cov roj nplua nyeem. Peb teev cov kev sib txuas tseem ceeb tshaj plaws:
- Qhov hnyav molecular calcium alkylsulfonate yog cov tshuaj ntxuav tes. Qhia tawm: 5%.
- Zinc dialkyldithiophosphate (Zn-DADTP) - tiv thaiv cov hlau nto los ntawm oxidation thiab txhua yam puas. Cov ntsiab lus: 2%.
- Polymethylsiloxane - tshav kub-stabilizing (anti-foam) additive nrog ib feem ntawm 0,004%
- Polyalkenylsuccinimide yog detergent-dispersant additive, uas yog qhia ua ke nrog anti-corrosion agents nyob rau hauv ib tug npaum li ntawm txog li 2%.
- Polyalkyl methacrylates yog depressant additives uas tiv thaiv cov nag lossis daus ntawm polymers thaum qhov kub thiab txias. Qhia tawm: tsawg dua 1%.
Nrog rau cov kev hloov kho uas tau piav qhia saum toj no, cov roj hluavtaws ua tiav thiab cov khoom siv hluavtaws tuaj yeem muaj cov demulsifying, siab siab thiab lwm yam khoom ntxiv. Tag nrho cov feem pua ntawm cov pob ntawm kev hloov pauv tsis pub dhau 10-11%. Txawm li cas los xij, qee hom roj hluavtaws tau tso cai kom muaj cov tshuaj ntxiv txog 25%.
