Muaj peb hom kev hloov xim silica gel desiccant: xiav silica gel desiccant, cobalt-dawb txiv kab ntxwv silica gel desiccant, thiab cobalt-dawb xiav silica gel desiccant.
(1) Qhov laj thawj tseem ceeb ntawm kev hloov xim ntawm xiav silica gel desiccant (xiav rau liab) yog suav nrog cobalt dichloride.
Cobalt dichloride nws tus kheej muaj tus yam ntxwv ntawm kev hloov ntawm xiav mus rau liab vim yog dej nqus. Toxic, yuav tsum tsis txhob sib cuag nrog zaub mov thiab nqus pa, yog tias muaj teeb meem lom, koj yuav tsum nrhiav kev kho mob tam sim ntawd.
(2), cobalt-free txiv kab ntxwv silica gel desiccant (txiv kab ntxwv mus rau tsaus ntsuab) discoloration yog vim muaj methyl violet.
Methyl violet hloov xim vim pH hloov. Nws siv lub hauv paus ntsiab lus uas "methyl txiv kab ntxwv → tsaus ntsuab" tshwm sim nyob rau hauv thaj tsam ntawm pH 0.13-0.5.
(3) Lub ntsiab yog vim li cas rau discoloration ntawm cobalt-dawb xiav silica gel desiccant (daj mus rau liab) yog lub xub ntiag ntawm Congo liab, uas yog tam sim no tsis tshua muaj siv.
Congo liab nws tus kheej yog siv los ua cov kua qaub-puag qhia nrog kev hloov xim ntawm 3.5 txog 5.2, lub xeev alkali ntawm liab, thiab cov kua qaub ntawm xiav-violet.
