Poov tshuaj carbonate

Los ntawm cov tsis muaj zog carbonic acid (nws yog me ntsis resistant thiab yuav tsuas muaj nyob rau hauv nta kev daws teeb meem) los ntawm reacting nrog alkalis thiab acidic nruab nrab tau ntsev yog tsis hu ua bicarbonates thiab carbonates, ntsig txog. Cov tshuaj tiv thaiv sib npaug yuav sau: H2CO3 + Koh → KHCO3 + H2O thiab H2CO3 + 2KOH → K2CO3 + 2H2O. Nyob rau hauv thawj lem ntawm poov tshuaj hydrogencarbonate, thiab lub thib ob - poov tshuaj carbonate. Formula acid ntsev - KHCO3, thiab hauv nruab nrab - K2CO3. Hniav puas loj ntawm poov tshuaj carbonate sib npaug zos rau 138,2 g / tus nas. Nyob rau hauv tsos tsa ntsev dawb crystalline hmoov, uas yog tsis combustible, melts nyob rau hauv 891 C, tsis muaj ncav lub kub taw tes, lub ntsev decomposes. Poov tshuaj carbonate hygroscopic, nkag soluble nyob rau hauv dej: 100 ml ntawm 20 ° C - 110,5 g, thiab nyob rau ntawm 100 C - 156 g ntawm ntsev. Tab sis nyob rau hauv ib tug dej cawv los yog acetone, qhov no tshuaj tsis yaj.

Nyob rau hauv lub qub hnub ntawm poov tshuaj carbonate, hu ua potash, lo lus los ntawm cov Latin lub npe «potassa». Potash yog ib tug ntawm cov hiob ntsev, uas tau raug hu mus rau cov neeg ntev dhau los. Nyob rau hauv Teb chaws Europe, mus txog rau lub xyoo pua xeem, potash yog ib tug ntawm cov tseem ceeb tshaj plaws tshuaj uas muaj coj mus muag tus nqi. Nyob rau hauv Russia, rau zus tau tej cov potash los ntawm Peter lub Great nyob rau hauv 1721, lub monopoly yog tsim los pab. Tam sim no, lub teb chaws ntawm Lavxias teb sab Federation, raws li zoo raws li nyob rau hauv Armenia, Kazakhstan, Belarus, Ukraine, Turkmenistan, Moldova, Uzbekistan yog ib yam tshuaj uas tau kev pab los ntawm lub xeev tus qauv GOST 10690-73. Potash koom, raws li GOST 12.1.005-88 rau peb teeb meem chav kawm ntawv tshuaj, nyob rau hauv kev sib cuag nrog txheej week los yog noo daim tawv nqaij ua rau voos.

Yog hais tias lub mix ntawm poov tshuaj carbonate nrog dej, ces ib tug ntau ntawm tshav kub thaum lub sij hawm nws xaus, i.e. K2CO3 hydrolysis cov tshuaj tiv thaiv yog exothermic, thiab nyob rau hauv qhov kev txiav txim ntawm cov dej hauv lub tsim ntawm tshiab tshuaj. Dibasic ntsev ntawm carbonic acid yog hydrolyzed stepwise. Thawj tsim acid ntsev: H2O + K2CO3 → KHCO3 + Koh. Ces, lub thib ob theem hais tsis zoo dej decomposition twb acid ntsev: H2O + KHCO3 → H2CO3 + Koh. Txij li thaum lub hydrolysis ntawm poov tshuaj carbonate li zoo li lwm yam ntsev ntawm muaj zog acids proceeds nrog lub tsim ntawm hydroxyl ions OH-, lub pH ntawm lawv aqueous daws yog yeej ib txwm siab tshaj 7, thiab qhov nruab nrab yog alkaline.

Potash nyob rau hauv lub xyoo pua 17th nyob rau hauv Russia twb tau los ntawm leaching ntoo ashes. Nyob rau hauv cov ntoo troughs tau npaj alkali tshuaj, txau dej sov tshauv. Cov tshuaj no yog ces poured rau hauv ib tug cib qhov cub nrog hlawv taws. Poov tshuaj carbonate twb crystallized heev ntom txheej rau hauv qab ntawm lub hearth los ntawm ib tug seem potash rho thiab pw rau ntawm tej kas tham, clogging lawv hermetically. Yuav tsum tau ib tug tej yam kev txawj, rau cov tshuaj twb evaporated, thiab qhov hluav taws kub tsis proffer. Yog li ntawd, cov khoom siv tes ua "polivachey" pib qhia nyob rau hauv lawv cov hluas, thiab tsuas yog tom qab ib tug ob peb xyoos ua hauj lwm mas yuav kis tau tej yam kev txawj ntse thiab ua ib tug tswv ntawm nws khoom siv tes ua. Piv txwv li: Cov burning hluav taws kub ib txwm tsim ntoo av tshauv dawb, qhov loj ib feem ntawm nws - yog potash. Niaj hnub no los siv lwm yam kev txheej txheem - tau los ntawm electrolysis ntawm poov tshuaj hydroxide twb dhau carbon dioxide: 2KOH → K2CO3 + CO2 + H2O. Cov no ib tug potash thiab dej.

poov tshuaj carbonate yog siv nyob rau hauv qhov siv thiab ua soaps thiab iav. Nyob rau hauv lub laboratory, nws yog siv raws li ib tug me me desiccant nyob rau hauv tus neeg mob thaum lwm cov neeg ua hauj xws li calcium chloride los yog magnesium sulfate, yog tsis pub ua. Nws yog tsis haum rau kom qhuav acidic tebchaw, tiam sis tej zaum yuav siv tau rau lub kom qhuav ntawm organic khoom nrog ib tug tsawg cov ntsiab lus ntawm acidic impurities. Poov tshuaj carbonate yog siv rau sib ntaus sib tua hluav taws kub ntawm cov chav kawm ntawv B, txij li thaum nws yog hais txog cov tshuaj hmoov thiab muaj peev xwm ntawm inhibiting thiab tua cov combustion txheej txheem. Nws muaj ib tug ntau dua extinguishing efficiency tshaj ntsev xws li sodium carbonate, sodium sulfate, sodium tshuaj fluoride los yog sodium hydrogen carbonate. Nws inhibitory efficiency ntawm combustion dab tseem yog siab tshaj uas ntawm sodium carbonate, sodium sulfate, txhuas oxide thiab calcium carbonate. Nyob rau hauv lub khob lag luam K2CO3 yog siv nyob rau hauv qhuav ntawm laboratory (refractory), kho qhov muag los yog potash iav, thiab khob rau glassware siv thiab ua. Nyob rau hauv tas li ntawd, potash thov nyob rau hauv cov tshuaj, ua liaj ua teb, kev kho mob thiab cov zaub mov industries.