Nitrobenzene yog dab tsi? Qhov no yog ib qho organic compound uas yog ib tug muaj zog nucleus thiab ib pawg nitro txuas rau nws. Nyob rau hauv tsos, nyob ntawm qhov kub thiab txias, lawv yog ci daj crystals los yog oily kua. Nws muaj almond tsw. Toxic.
qauv qauv ntawm nitrobenzene
Cov pab pawg nitro yog cov khoom siv hluav taws xob muaj zog heev. Yog li ntawd, nitrobenzene molecule muaj qhov tsis zoo inductive thiab tsis zoo mesomeric nyhuv. Cov pab pawg nitro heev nyiam cov electron ntom ntom ntawm cov ntxhiab tsw qab, ua rau nws tsis ua haujlwm. Electrophilic reagents yog tsis nyiam mus rau lub nucleus yog li ntawd, thiab yog li ntawd nitrobenzene tsis yog li ntawd nquag koom nyob rau hauv xws li tshwm sim. Txhawm rau ncaj qha ntxiv lwm pab pawg nitro rau nitrobenzene, yuav tsum muaj kev mob hnyav heev, yuav tsum nruj dua li kev sib txuas ntawm mononitrobenzene. Tib yam siv rau halogens, sulfo pawg, thiab lwm yam.
Los ntawm cov qauv qauv ntawm nitrobenzene nws tuaj yeem pom tias ib daim ntawv cog lus ntawm nitrogen nrog oxygen yog ib leeg, thiab lwm qhov yog ob npaug. Tab sis qhov tseeb, vim yog cov nyhuv mesomeric, lawv yog ob qho tib si sib npaug thiab muaj qhov ntev ntawm 0.123 nm.
Tau txais nitrobenzene hauv kev lag luam
Nitrobenzene yog ib qho tseem ceeb nruab nrab ntawm kev sib txuas ntawm ntau yam tshuaj. Yog li ntawd, nws yog tsim nyob rau hauv ib tug industrial scale. Txoj hauv kev tseem ceeb kom tau txais nitrobenzene yog nitration ntawm benzene. Feem ntau, kev sib xyaw nitrating (ib qho sib xyaw ntawm sulfuric thiab nitric acid) yog siv rau qhov no. Cov tshuaj tiv thaiv yog nqa tawm rau 45 feeb ntawm qhov kub ntawm txog 50 ° C. Cov txiaj ntsig ntawm nitrobenzene yog 98%. Tias yog vim li cas txoj kev no feem ntau yog siv hauv kev lag luam. Rau nws qhov kev siv, muaj cov kev teeb tsa tshwj xeeb ntawm ob qho tib si ntu thiab txuas ntxiv. Xyoo 1995, US nitrobenzene ntau lawm yog 748,000 tons hauv ib xyoos.
Nitration ntawm benzene kuj tseem tuaj yeem ua tau yooj yim nrog cov concentrated nitric acid, tab sis nyob rau hauv cov ntaub ntawv no cov txiaj ntsig ntawm cov khoom yuav qis dua.
Tau txais nitrobenzene hauv chav kuaj
Muaj lwm txoj hauv kev kom tau nitrobenzene. Aniline (aminobenzene) yog siv los ua raw khoom, uas yog oxidized nrog peroxy compounds. Vim li no, pawg amino yog hloov los ntawm ib pawg nitro. Tab sis thaum lub sij hawm no cov tshuaj tiv thaiv, ob peb by-products yog tsim, uas tiv thaiv kev siv ntawm no txoj kev nyob rau hauv kev lag luam. Ntxiv mus, nitrobenzene tsuas yog siv rau kev sib txuas ntawm aniline, yog li nws tsis muaj kev nkag siab siv aniline rau kev tsim cov nitrobenzene.
Lub cev muaj zog
Nyob rau hauv chav tsev kub, nitrobenzene yog cov xim tsis muaj xim oily kua nrog iab almond tsw. Ntawm qhov kub ntawm 5.8 ° C, nwshardens rau hauv daj crystals. Nitrobenzene boils ntawm 211 ° C, thiab ignites spontaneously ntawm 482 ° C. Cov tshuaj no, yuav luag zoo li cov tshuaj tsw qab, yog insoluble hauv dej, tab sis nws yog heev soluble nyob rau hauv cov organic tebchaw, tshwj xeeb tshaj yog nyob rau hauv benzene. Nws kuj tseem tuaj yeem ua tau chav distilled.
Electrophilic hloov pauv
Rau nitrobenzene, xws li rau ib qho chaw, kev cuam tshuam ntawm electrophilic hloov mus rau hauv lub nucleus yog tus yam ntxwv, txawm hais tias lawv nyuaj me ntsis piv rau benzene vim muaj kev cuam tshuam ntawm pawg nitro. Yog li, dinitrobenzene tuaj yeem tau los ntawm nitrobenzene los ntawm nitration ntxiv nrog kev sib xyaw ntawm nitric thiab sulfuric acids ntawm qhov kub siab. Cov khoom tsim tawm yuav muaj feem ntau (93%) muaj cov meta-dinitrobenzene. Nws tseem tuaj yeem tau txais trinitrobenzene ncaj qha. Tab sis rau qhov no nws yog ib qho tsim nyog yuav tsum siv cov xwm txheej nruj dua, nrog rau boron trifluoride.
Ib yam nkaus, nitrobenzene tuaj yeem ua sulfonated. Txhawm rau ua qhov no, siv tus neeg sawv cev muaj zog heev - oleum (kev daws teeb meem ntawm sulfur oxide VI hauv sulfuric acid). Qhov kub ntawm cov tshuaj tiv thaiv sib tov yuav tsum yog tsawg kawg 80 ° C. Lwm cov tshuaj tiv thaiv electrophilic hloov pauv yog ncaj qha halogenation. Muaj zog Lewis acids (aluminium chloride, boron trifluoride, thiab lwm yam) thiab kub siab yog siv los ua catalysts.
Nucleophilic hloov pauv
Raws li tuaj yeem pom los ntawm cov qauv qauv, nitrobenzene tuaj yeem cuam tshuam nrog cov khoom siv hluav taws xob muaj zog. Qhov no yogTej zaum vim yog kev cuam tshuam ntawm pawg nitro. Ib qho piv txwv ntawm cov tshuaj tiv thaiv no yog kev cuam tshuam nrog cov concentrated lossis cov khoom hydroxides ntawm alkali hlau. Tab sis qhov tshuaj tiv thaiv no tsis tsim sodium nitrobenzene. Cov tshuaj formula ntawm nitrobenzene es qhia ntxiv ntawm ib pawg hydroxyl rau cov tub ntxhais, piv txwv li, tsim ntawm nitrophenol. Tab sis qhov no tshwm sim tsuas yog nyob rau hauv qhov hnyav hnyav.
Cov tshuaj tiv thaiv zoo sib xws tshwm sim nrog cov tshuaj organomagnesium. Cov hydrocarbon radical txuas mus rau lub nucleus nyob rau hauv ortho los yog para txoj hauj lwm mus rau pawg nitro. Ib sab txheej txheem nyob rau hauv cov ntaub ntawv no yog txo cov nitro pawg rau cov amino pawg. Nucleophilic hloov pauv cov tshuaj tiv thaiv yooj yim dua yog tias muaj ntau pawg nitro, vim lawv yuav rub cov electron ceev ntawm lub nucleus ntau dua.
Txoj kev xav rov qab
Raws li koj paub, cov tshuaj nitro tuaj yeem txo qis rau amines. Nitrobenzene tsis muaj qhov tshwj xeeb, cov qauv uas qhia txog qhov muaj peev xwm ntawm cov tshuaj tiv thaiv no. Nws feem ntau siv hauv kev lag luam rau kev sib txuas ntawm aniline.
Tab sis nitrobenzene tuaj yeem muab ntau yam khoom siv rov qab los. Feem ntau, kev txo qis nrog atomic hydrogen yog siv thaum lub sijhawm tso tawm, piv txwv li, cov tshuaj tiv thaiv acid-hlau yog ua nyob rau hauv cov tshuaj tiv thaiv sib tov, thiab cov tshuaj tso tawm hydrogen reacts nrog nitrobenzene. Feem ntau, qhov kev cuam tshuam no tsim aniline.
Yog tias nitrobenzene raug kho nrog zinc plua plav hauv cov tshuaj ammonium chloride, cov tshuaj tiv thaiv yuav yog N-phenylhydroxylamine. Cov tshuaj no tuaj yeem txo qis rau aniline hauv tus qauv, lossis oxidized rov qab mus rau nitrobenzene nrog cov oxidizing muaj zog.
Txo tuaj yeem ua rau theem roj nrog molecular hydrogen nyob rau hauv muaj platinum, palladium lossis npib tsib xee. Hauv qhov no, aniline kuj tau txais, tab sis muaj peev xwm txo qis ntawm benzene nplhaib nws tus kheej, uas feem ntau tsis xav tau. Qee zaum ib qho catalyst xws li Raney npib tsib xee kuj siv. Nws yog npib tsib xee, saturated nrog hydrogen thiab muaj 15% txhuas.
Thaum nitrobenzene txo los ntawm potassium lossis sodium cawv, azoxybenzene tsim. Yog tias koj siv cov tshuaj txo qis hauv qhov chaw alkaline, koj tau txais azobenzene. Cov tshuaj tiv thaiv no kuj tseem ceeb heev, txij li qee qhov dyes yog synthesized nrog nws cov kev pab. Azobenzene tuaj yeem raug txo qis ntxiv hauv qhov nruab nrab alkaline los tsim hydrazobenzene.
Thaum pib, qhov txo qis ntawm nitrobenzene tau ua nrog ammonium sulfide. Txoj kev no tau npaj rau xyoo 1842 los ntawm N. N. Zinin, yog li cov tshuaj tiv thaiv nws lub npe. Tab sis tam sim no nws tsis tshua muaj siv nyob rau hauv kev xyaum vim tsis tshua muaj yield.
Daim ntawv thov
Nitrobenzene nws tus kheej yog siv tsawg heev, tsuas yog siv cov kuab tshuaj (piv txwv li, rau cellulose ethers) lossis tus neeg sawv cev oxidizing me me. Nws yog qee zaum ntxiv rau cov kev daws teeb meem hlau polishing.
Yuav luag tag nrho cov khoom tsim nitrobenzene yog siv rau kev sib txuas ntawm lwm yam khoom siv (piv txwv li, aniline), uas, dhau los,siv rau kev sib txuas ntawm cov tshuaj, dyes, polymers, explosives, thiab lwm yam.
Danger
Vim nws lub cev thiab tshuaj lom neeg, nitrobenzene yog ib qho chaw txaus ntshai heev. Nws muaj kev phom sij txog kev noj qab haus huv qib peb ntawm plaub hauv qab NFPA 704. Ntxiv rau qhov nqus tau los ntawm cov mucous daim nyias nyias, nws kuj tau nqus los ntawm daim tawv nqaij. Thaum lom los ntawm ib tug loj concentration ntawm nitrobenzene, ib tug neeg yuav poob tsis nco qab thiab tuag. Ntawm qhov tsis tshua muaj siab, cov tsos mob ntawm kev lom muaj xws li malaise, kiv taub hau, tinnitus, xeev siab thiab ntuav. Ib qho tshwj xeeb ntawm nitrobenzene lom yog qhov siab ntawm tus kab mob. Cov tsos mob tshwm sim sai heev: reflexes cuam tshuam, cov ntshav yuav tsaus xim av vim yog tsim ntawm methemoglobin hauv nws. Qee zaum yuav muaj pob khaus ntawm daim tawv nqaij. Qhov concentration txaus rau kev tswj hwm yog tsawg heev, txawm hais tias tsis muaj cov ntaub ntawv qhia tseeb ntawm cov koob tshuaj tuag. Cov ntaub ntawv feem ntau pom muaj nyob rau hauv cov ntaub ntawv tshwj xeeb uas 1-2 tee ntawm nitrobenzene txaus los tua ib tug neeg.
Kev kho mob
Yog tias muaj nitrobenzene lom, tus neeg raug tsim txom yuav tsum raug tshem tawm tam sim ntawd ntawm qhov chaw muaj tshuaj lom thiab tshem tawm cov khaub ncaws tsis huv. Lub cev yog ntxuav nrog dej sov soapy kom tshem tawm nitrobenzene ntawm daim tawv nqaij. Txhua 15 feeb, tus neeg raug tsim txom tau nqus cov pa roj carbon monoxide. Rau kev lom me me, cystamine, pyridoxine, lossis lipoic acid yuav tsum tau noj. Hauv cov xwm txheej hnyav dua, cov tshuaj methylene xiav lossis chromosmon raug pom zoo. Ntawmlom nrog nitrobeznol los ntawm lub qhov ncauj, nws yog ib qho tsim nyog yuav tsum tam sim ntawd ntuav thiab yaug lub plab nrog dej sov. Nws yog contraindicated noj cov rog, nrog rau cov mis nyuj.
