Thioacetic acid, chemical formula CH3C (S) H, yog sulfur-muaj organic acid feem ntau siv hauv cov organic synthesis thiab kev lag luam tshuaj. Daim ntawv no yuav qhia txog cov txheej txheem tshuaj synthesis thiab cov kauj ruam ntawm Thioacetic acid hauv chav kuaj thiab kev lag luam tshuaj lom neeg loj raws li cov xwm txheej sib txawv.
1, Laboratory synthesis txoj kev
Thioacetic acid tuaj yeem tau txais los ntawm cov tshuaj tiv thaiv ntawm thioacetyl chloride thiab nickel hydrate hauv chav kuaj. Cov kauj ruam tshwj xeeb yog raws li nram no:
1.1 Ua ntej ntxiv 5 mL ntawm n-butyl lithium (1.6 mol / L) tov rau 100 mL ntawm anhydrous chloroform, txias rau 0 degree C, ces poob 6 mL ntawm chloroform tov ntawm thioacetic acid. (0.1 mol / L), tswj qhov kub ntawm 0-5 degree C, thiab cia sawv ntsug rau 10-15 feeb.
1.2 Tom qab cov tshuaj tiv thaiv, ntxiv 10 mL ntawm cov dej deionized, kho tus nqi pH rau 5.5-6.5, thiab cov tshuaj hloov cov txiv kab ntxwv.
1.3 Ntxiv cov tshuaj rau hauv pre-cooled npib tsib xee hydrate (0.1 mol/L) tov rau cov tshuaj tiv thaiv rau 1 h, thiab tswj qhov kub ntawm 0-5 degree C.
1.4 Tom qab cov tshuaj tiv thaiv, lim cov tshuaj tiv thaiv kom tau txais lub teeb daj Thioacetic acid crystal. Yaug nrog acetic acid thiab qhuav.
2, Txoj kev loj chemical synthesis
Thioacetic acid tuaj yeem tsim los ntawm sodium carbonate sulfuration hauv kev lag luam tshuaj lom neeg loj. Cov kauj ruam tshwj xeeb yog raws li nram no:
2.1 Ntxiv 1.9 kg ntawm sodium carbonate rau hauv lub reactor thiab ntxiv cov dej kom zoo kom yaj nws.
2.2 Hydrolysis kauj ruam: nyob rau hauv ib txwm kub, maj mam ntxiv 220L hydrogen sulfide gas (99.99 feem pua) mus rau hauv lub reactor, cov roj ntws yog 20L / min, thiab cua sov tib lub sijhawm, tswj qhov kub ntawm 60-80 degree C, thiab teb rau 3-4 teev.
2.3 Txhawm rau kom ntseeg tau tias cov tshuaj tiv thaiv tiav, tus nqi ntawm ob peb pawg ntawm cov tshuaj tiv thaiv tuaj yeem sib piv. Thaum tus nqi ruaj khov, ntxiv sodium hydroxide txaus synchronously ua kom tus nqi pH ntawm cov tshuaj tiv thaiv txog li 7.0, thiab cov tshuaj tiv thaiv tiav.
2.4 Ces cov tshuaj tiv thaiv yog rhuab thiab concentrated, thiab cov concentration yog tswj mus rau 16-20 degree Bx. Tom qab ntawd cov tshuaj tiv thaiv yog muab tso rau hauv lub tank bleaching rau decolorization, thiab lim dua kom tau ib lub teeb daj-xim av kua uas muaj Thioacetic acid.
2.5 Thaum kawg, ntxiv cov kua rau hauv ntauwd distillation thiab distilled thiab purify nws kom tau cov ntshiab Thioacetic acid.
Summary: Cov saum toj no yog cov tshuaj synthesis txoj kev thiab cov kauj ruam ntawm Thioacetic acid nyob rau hauv lub chav kuaj thiab loj chemical kev lag luam. Thioacetic acid tuaj yeem tsim los ntawm cov tshuaj tiv thaiv ntawm thioacetic acid thiab npib tsib xee hydrate hauv chav kuaj, thaum sodium carbonate sulfuration txoj kev siv hauv kev lag luam tshuaj loj, thiab cov ntshiab Thioacetic acid thaum kawg tau txais tom qab decolorization thiab distillation purification.
Thioacetic acid yog cov organic sulfur compound nrog cov tshuaj tiv thaiv muaj zog. Nov yog qee qhov ntawm nws cov tshuaj tiv thaiv:
1. Cov tshuaj tiv thaiv alkali: Thioacetic acid tuaj yeem hnov mob nrog alkali los tsim cov ntsev sib xws, xws li:
CH3C(S)SH plus NaOH → CH3C(S) Na plus H2O
2. Cov tshuaj tiv thaiv oxidation: Thioacetic acid tuaj yeem oxidized rau cov kua qaub los ntawm oxidant xws li hydrogen peroxide, piv txwv li:
CH3C(S)SH plus H2O2→ CH3C(S)OH plus H2O plus S
3. Cov tshuaj tiv thaiv decarboxylation: Thioacetic acid tuaj yeem tsim cov mercaptan sib xws los ntawm cov tshuaj tiv thaiv decarboxylation, piv txwv li:
CH3C(S)SH → CH3SH plus CO
4. Alkylation cov tshuaj tiv thaiv: Thioacetic acid tuaj yeem hnov mob nrog alkyl halides, xws li:
CH3C(S) SH plus CH3Ib → CH3C(S)SCH3
5. Cov tshuaj tiv thaiv nrog cov hlau ions: Thioacetic acid tuaj yeem cuam tshuam nrog qee cov hlau ions, xws li:
CH3C(S)SH plus Cu2 plus→ [Cu(CH3C(S)S)]2 plus
Hauv luv luv, Thioacetic acid muaj ntau yam tshuaj tiv thaiv thiab tuaj yeem cuam tshuam nrog ntau lub tebchaw.
Thioacetic acid yog cov organic compound uas muaj sulfur. Nws txoj kev loj hlob keeb kwm tuaj yeem taug qab mus rau qhov kawg ntawm xyoo pua 19th. Cov hauv qab no yog cov lus qhia luv luv ntawm nws keeb kwm kev loj hlob:
Nyob rau hauv 1887, Fabkis chemist Marcelin Berthelot thawj zaug synthesized ib tug compound zoo li Thioacetic acid, uas nws hu ua "acide thioac é tique".
Xyoo 1895, German chemist Arthur Hantzsch synthesized Thioacetic acid zoo ib yam, thiab pom qee yam tseem ceeb ntawm nws, xws li volatile, pungent tsw, thiab muaj peev xwm tsim cov pawg.
Thaum pib ntawm lub xyoo pua 20th, German chemist Carl Duisberg pib kawm txog kev npaj thiab tshuaj lom neeg ntawm Thioacetic acid, thiab luam tawm ib daim ntawv ntawm kev sib txuas ntawm Thioacetic acid nyob rau hauv 1903.
Txij thaum pib ntawm lub xyoo pua 20th mus rau nruab nrab ntawm lub xyoo pua 20th, kev tshawb fawb ntawm Thioacetic acid maj mam nkag siab, tsis tsuas yog txhim kho nws txoj kev npaj, tab sis kuj pom nws daim ntawv thov hauv biology, tshuaj thiab lwm yam kev lag luam, xws li siv los ua raw khoom tseem ceeb. cov khoom siv hauv tshuaj synthesis.
Txog tam sim no, kev tshawb fawb ntawm Thioacetic acid tseem txuas ntxiv mus, thiab tib neeg tab tom tshawb nrhiav nws txoj kev siv dav hauv cov organic synthesis, tshuaj lom neeg lom neeg thiab lwm yam haujlwm.