Methanol - dab tsi yog cov khoom no? Khoom, ntau lawm thiab siv methanol

2024 Tus sau: Angel Austin | [email protected]. Kawg hloov kho: 2023-12-17 05:28

Tsis zoo li hydrocarbons, oxygen-muaj cov organic tshuaj muaj cov atoms complex hu ua pawg ua haujlwm. Methanol yog cov dej cawv saturated uas muaj pawg hydroxyl hauv nws cov molecule. Nws txhais cov yam ntxwv tseem ceeb ntawm no compound. Hauv peb tsab xov xwm, peb yuav saib txoj hauv kev tsim cov tshuaj methyl cawv, cov tshuaj tiv thaiv tseem ceeb tshaj plaws thiab kev siv methanol.

Cov qauv ntawm cov molecule

Yuav kom paub cov qauv ntawm methyl cawv, koj yuav tsum nco ntsoov tias hom molecule twg muaj qhov yooj yim tshaj plaws saturated hydrocarbon - methane. Nws tau nthuav tawm raws li CH ₄ thiab muaj ib lub atom sib koom ua ke ntawm cov sigma daim ntawv cog lus yooj yim rau hydrogen atoms.

Yog tias ib qho ntawm lawv hloov los ntawm pawg hydroxyl -OH, peb tau txais cov qauv CH₃OH. Nws yog methanol. Lub kaum sab xis tsim los ntawm cov kev taw qhia ntawm C-O-H daim ntawv cog lus yog kwv yees li 110⁰, yog li cov molecules ntawm monohydric alcohols muaj cov duab angular. Nrog rau qhov tseeb tiascov electronegativity ntawm oxygen (3.5 eV) yog ntau dua li ntawm cov pa roj carbon (2.5 eV), cov pa oxygen-carbon daim ntawv cog lus yog polarized heev, thiab pawg hydroxo plays lub luag hauj lwm ntawm ib tug hloov uas muaj ib tug tsis zoo inductive nyhuv. Yog li, methanol yog ib qho cawv uas nws lub sijhawm dipole yog 1.69D.

Nomenclature

Cia peb xav txog peb txoj hauv kev los tsim lub npe ntawm cov tshuaj nrog cov mis CH₃OH. Keeb kwm, nws yog muab los ntawm lub npe ntawm hydrocarbon radical uas pawg hydroxyl tau txuas nrog. Cov radical CH₃ yog methyl, yog li CH₃OH hu ua methyl cawv. Raws li Geneva nomenclature, lub ntsiab lus -ol yog ntxiv rau lub npe ntawm cov khoom siv hydrocarbon - alkane. Lub compound yuav raug hu ua methanol. Lub npe no feem ntau siv thiab siv ntau zaus. Nyob rau hauv rational nomenclature, cov compound peb tab tom xav txog yog hu ua carbinol.

Lub cev muaj zog

Cov cawv qis uas muaj txog li peb cov pa roj carbon atom, uas suav nrog methanol, yog cov kua uas sib xyaw nrog dej hauv txhua qhov sib npaug. Carbinol muaj qhov hnov ntxhiab tsw ntxhiab, tab sis tsis tsim nyog rau kev noj, vim nws yog qhov muaj zog tshaj plaws neurotoxic compound. Nws qhov ceev yog tsawg dua kev sib sau thiab yog 0.791 D₄²⁰. Cov ntsiab lus melting thiab boiling yog -97.9 ⁰C thiab +94.5 ⁰C feem.

Kev tsim cov tshuaj methanol

Hydrolysis ntawm cov sib thooj haloalkyls nyob rau hauv lub xub ntiag ntawm hydroxides ntawm active hlau, piv txwv li, alkali los yog alkaline ntiaj teb, thiab thaum rhuab -Qhov no yog ib txoj hauv kev kom tau txais carbinol. Cov tshuaj chlorine lossis bromomethane raug coj los ua cov khoom pib, qhov tshwm sim ntawm cov tshuaj tiv thaiv yuav yog kev hloov ntawm halogen atom nrog cov pab pawg ua haujlwm -OH thiab kev tsim cov methanol.

Lwm txoj hauv kev ua rau kev tsim cov dej cawv thawj zaug yog txo cov aldehydes lossis carboxylic acids. Rau cov tshuaj tiv thaiv redox no, muaj zog txo cov neeg ua haujlwm xws li sodium borohydride lossis lithium aluminium hydride yog siv. Cov tshuaj pib yog formic acid lossis formaldehyde. Ib txoj hauv kev niaj hnub kom tau txais carbinol yog nws cov khoom sib txuas los ntawm carbon, dej, hydrogen thiab carbon monoxide. Cov txheej txheem yuav siv qhov chaw ntawm qhov kub ntawm +250 ° C, siab siab thiab muaj zinc thiab tooj liab oxides ua catalysts. Tshiab, tab sis kev lag luam ncaj ncees, yog txoj hauv kev tau txais cawv los ntawm microscopic algae ntawm dej hiav txwv thiab hiav txwv, cov biomass uas yog qhov loj heev. Cov nroj tsuag substrate yog fermented, lub liberated methane yog sau thiab ntxiv oxidized rau methanol. Qhov zoo ntawm biomethanol ntau lawm yog qhov tsis muaj qhov xav tau siv cov dej tshiab, hluav taws xob thiab kev ua kom huv ntawm cov thev naus laus zis.

organometallic synthesis

Yog tias cov organic tebchaw nrog cov pab pawg carbonyl hauv cov molecules raug kho nrog cov tshuaj organomagnesium, monohydric alcohols tuaj yeem tau. Organometallic reagents yog tsim los ntawm kev sib cuam tshuam ntawm magnesium hlau chips thiab bromine-muaj alkane derivatives nyob rau hauv qhuav diethyl.ether. Los ntawm formic aldehyde, cov tshuaj tiv thaiv no tuaj yeem siv tsis tau tsuas yog methanol xwb, kev siv uas txwv, tab sis kuj tseem muaj lwm yam cawv cawv.

Tshuaj yam ntxwv

Carbinol tsis muaj cov lus hais ntawm cov kua qaub lossis cov hauv paus, ntxiv rau, cov tshuaj aqueous ntawm cov tshuaj tsis cuam tshuam rau cov ntsuas. Cov tshuaj tiv thaiv methanol yog kev cuam tshuam nrog cov hlau nquag thiab carboxylic acids. Nyob rau hauv thawj rooj plaub, hlau alcoholates yog tsim, nyob rau hauv lub thib ob - esters. Piv txwv li, sodium displaces hydrogen atoms nyob rau hauv lub functional hydroxyl pab pawg neeg ntawm ib tug cawv:

2CH₃OH + 2Na=2CH₃ONa +H₂.

Cov tshuaj tiv thaiv ntawm methyl cawv thiab acetic acid ua rau tsim cov methyl acetate, los yog acetic acid methyl ester:

CH₃COOH+CH₃OH<--(H₂SO 4_)CH3_COOCH3_+H2_O.

Cov tshuaj tiv thaiv saum toj no yog hu ua esterification thiab yog qhov tseem ceeb tshaj plaws.

Oxidation ntawm cawv

Cov tshuaj methanol ua rau kev tsim cov aldehydes, xav txog qhov piv txwv ntawm nws kev cuam tshuam nrog tooj liab oxide. Yog hais tias ib tug liab-kub tooj liab hlau coated nrog oxide yog txo mus rau hauv ib tug methanol tov, ces muaj ib tug tshwj xeeb tsis kaj siab tsw ntawm formaldehyde. Thiab qhov dull nto ntawm cov hlau yuav ci thiab ci vim qhov txo qis ntawm cov tooj liab ntshiab.

Dehydration

Thaum rhuab thiab nyob rau hauv lub xub ntiag ntawm hygroscopic tshuaj, particles cais tawm ntawm cawv moleculesdej. Unsaturated hydrocarbons ntawm ethylene series tuaj yeem pom hauv cov khoom. Nyob rau hauv cov xwm txheej ntawm cov dej siab concentration thiab qhov kub thiab txias, ethers tuaj yeem tau txais. Yog li, dimethyl ether tuaj yeem tau los ntawm methanol.

Kev siv methyl cawv

Methyl cawv yog siv los ua ib qho inhibitor ntawm hydrates tsim nyob rau hauv cov kav dej, vim hais tias cov khoom tseem ceeb ntawm methanol yog solubility zoo nyob rau hauv dej thiab tsis tshua muaj freezing point. Lub ntsiab ntim ntawm methyl cawv yog siv los tsim cov phenol-formaldehyde resins. Lub siab octane tus yam ntxwv ntawm carbinol ua rau nws muaj peev xwm siv tau raws li ib puag ncig tus phooj ywg roj rau tsheb. Hauv kev lag luam xim, carbinol yog siv los ua cov kuab tshuaj.

Kev cuam tshuam ntawm methanol rau tib neeg lub cev

Ntoo cawv yog qhov tsis tsim nyog rau kev siv dej cawv, vim nws yog cov tshuaj muaj zog tshaj plaws. Ib zaug nyob rau hauv lub plab zom mov, nws pib oxidize rau formic acid thiab formic aldehyde. Oxidation cov khoom cuam tshuam rau lub paj hlwb thiab lub retina, uas muaj cov receptors. Qhov muag tsis pom kev teeb tsa hauv. Formic acid, uas muaj peev xwm sib sau ua ke, yog nqa los ntawm cov ntshav mus rau daim siab thiab ob lub raum, rhuav tshem cov kab mob tseem ceeb no. Raws li qhov tshwm sim ntawm methanol lom, qhov tshwm sim tuag tshwm sim, txij li cov txheej txheem ntawm kev ntxuav cov ntshav los ntawm cov metabolites tsis zoo.

Hauv peb tsab xov xwm, peb tau paub txog cov khoom, daim ntawv thov thiabtxoj kev kom tau methanol.