Nyob rau hauv niaj hnub inorganic chemistry, kev faib cov ntsev, kev sib cuam tshuam thiab cov khoom ntawm cov ntsiab lus thiab lawv ntau cov tebchaw yog qhov tseem ceeb heev. Muaj cov khoom uas, ntawm lwm tus, nyob hauv qhov chaw tshwj xeeb. Xws li cov tebchaw, tshwj xeeb, yuav tsum muaj calcium sulfate. Cov qauv ntawm cov tshuaj yog CaSO4.
Nco ntau qhov tso nyiaj ntawm cov khoom sib xyaw no hauv lub ntiaj teb cov pob zeb tso cai rau nws siv los ua cov khoom siv raw hauv kev tsim ntau yam khoom. Cov tshuaj uas tshwm sim tuaj yeem siv tau zoo hauv kev tsim kho, tshuaj thiab lwm yam.
Nyob rau hauv tej yam ntuj tso, deposits ntawm ib tug ntxhia nrog cov muaj pes tsawg leeg CaSO4 2 H2O yog pom. Calcium sulfate kuj pom nyob rau hauv hiav txwv (kwv yees li 1,800,000 tons ib cubic meter) thiab dej tshiab.
Anhydride CaSO4 yog cov hmoov dawb nrog qhov ntom ntawm 2.90-2.99 grams ib cubic centimeter. Lub compound nquag absorbs noo noo los ntawm huab cua. Vim yog cov cuab yeej no, calcium sulfate yog siv los ua kom qhuav.
Ntawm qhov kub ntawm ib txhiab plaub puas thiab tsib caug degrees, cov khoom melts thiab decomposes. Lub solubility ntawm ib yam khoom ncenyob rau hauv muaj HCl, HNO3, NaCl, MgCl2. Calcium sulfate reacts nrog sulfuric acid thiab txo thaum sintered nrog carbon.
Yog nyob rau hauv dej nrog rau MgSO4 thiab MgCl2, CaSO4 muab nws mus tas li hardness. Tshuaj softening ntawm cov kua yog ua tau nrog kev pab los ntawm reagents. Kev txo cov dej hardness yog ua raws li kev qhia txog cov khoom muaj txiaj ntsig nrog nws cov anions.
Dej softening kuj yog ua los ntawm kev sib pauv ion. Txoj kev no yog ua raws li lub peev xwm ntawm tus kheej cov khoom siv dag zog thiab ntuj ion exchangers - high-molecular compounds - los pauv cov radicals uas ua rau lawv muaj pes tsawg leeg rau cov ions tam sim no hauv cov tshuaj. Aluminosilicates (Na2 [Al2Si2O8]∙nH2O, piv txwv li) feem ntau ua raws li ion exchangers.
Hydrate nrog cov muaj pes tsawg leeg 2CaSO4 H2O - alabaster (burnt gypsum) - yog siv rau hauv kev tsim cov binders. Cov tshuaj no yog cov hmoov sib xyaw ua ke, los ntawm qhov uas, thaum tov nrog dej, cov khoom yas yog thawj zaug, thiab tom qab ntawd hardened rau hauv ib qho khoom loj. Tau txais alabaster yog nqa tawm nyob rau hauv tus txheej txheem ntawm firing gypsum nyob rau hauv lub cawv ntawm ib puas thiab tsib caug rau ib puas thiab xya caum degrees. Cov cuab yeej no yog siv rau hauv kev tsim cov vaj huam sib luag thiab slabs, cam khwb cia ntawm cov khoom, nrog rau kev siv cov plaster ua haujlwm.
Roasting nyob rau hauv qhov kub ntawm ntau tshaj li ob puas degrees ua rau tsim ib daim ntawv soluble ntawm anhydrous calcium sulfate, ntawm qhov kub ntawm ntau tshaj tsib puas degrees - ib daim ntawv insoluble. Qhov kawg poob nws lub peev xwmtxuas dej, yog li nws tsis tuaj yeem siv los ua tus khi.
Natural gypsum tuaj yeem siv los ua cov khoom lag luam thawj zaug hauv kev tsim cov cement thiab sulfuric acid los ntawm kev sib xyaw ua ke.
Natural calcium sulfate kuj tseem siv tau los ua cov tshuaj desiccant hauv kev tshuaj xyuas cov organic tebchaw. Ib qho anhydrous compound muaj peev xwm nqus tau 6.6% ntawm noo noo los ntawm tag nrho cov huab hwm coj. Calcium sulfate kuj tseem siv rau hauv kev tsim cov khoom siv thermal rwb thaiv tsev.
