Zisebenza njani iiMolecular Sieves?

i-molecular sieve yimathiriyeli enemingxuma enemingxuma emincinci kakhulu, enobungakanani obufanayo. Isebenza njenge-sieve yekhitshi, ngaphandle komlinganiselo we-molecular, ukwahlula imixube yegesi equlethe iimolekyuli ezininzi. Kuphela ziimolekyuli ezincinci kunee pores ezinokudlula; kanti, iimolekyuli ezinkulu zivaliwe. Ukuba iimolekyuli ofuna ukuzahlula zilingana ngobukhulu, i-molecular sieve inokwahlula nge-polarity. I-Sieves isetyenziswe kwizicelo ezahlukeneyo njengobumanzi obususa i-desiccants kwaye inceda ukuthintela ukuthotywa kweemveliso.

Iintlobo zeeSieves zeMolekyuli

Iisefu zemolekyuli ziza kwiindidi ezahlukeneyo ezifana ne-3A, 4A, 5A kunye ne-13X. Amanani amanani achaza ubungakanani bepore kunye nokwakheka kweekhemikhali ze-sieve. I-ion ye-potassium, i-sodium, kunye ne-calcium iguqulwa ekubunjweni ukulawula ubungakanani bepore. Kukho amanani ahlukeneyo e-meshes kwiisefu ezahlukeneyo. Isefa yemolekyuli enenani elincinane leemeshes isetyenziselwa ukwahlula iigesi, kwaye enye enemeshes eninzi isetyenziselwa ulwelo. Ezinye iiparameters ezibalulekileyo ze-molecular sieves ziquka ifom (umgubo okanye i-bead), ubuninzi bobuninzi, amanqanaba e-pH, amaqondo okushisa okuvuselela (ukusebenza), umswakama, njl.

I-Molecular Sieve vs. Silica Gel

Ijeli ye-silica ingasetyenziselwa njengomswakama osusa i-desiccant kodwa ihluke kakhulu kwi-sieve ye-molecular. Izinto ezahlukeneyo ezinokuthi ziqwalaselwe ngelixa ukhetha phakathi kwezi zimbini zikhetho zendibano, utshintsho kuxinzelelo, amanqanaba okufuma, amandla omatshini, uluhlu lweqondo lokushisa, njl.

Umlinganiselo we-adsorption ye-molecular sieve inkulu kune-silica gel. Oku kungenxa yokuba isisefu sisixhobo esomisa ngokukhawuleza.

I-molecular sieve isebenza ngcono kune-silica gel kumaqondo obushushu aphezulu, njengoko inesakhiwo esifanayo esibopha amanzi ngamandla.

Kwi-Relative Humidity ephantsi, umthamo we-molecular sieve ungcono kakhulu kunowejeli ye-silica.

Isakhiwo se-molecular sieve sichazwa kwaye sinemibhobho efanayo, ngelixa isakhiwo se-silica gel si-amorphous kunye neepores ezininzi ezingaqhelekanga.

Uzivula njani iiSieves zeMolekyuli

Ukwenza iisefu ze-molecular zisebenze, imfuneko esisiseko kukuvezwa kumaqondo obushushu aphezulu kakhulu, kwaye ubushushu kufuneka bube phezulu ngokwaneleyo ukuze i-adsorbate ibe ngumphunga. Ubushushu buya kuhluka kunye nezinto ezibhengezwayo kunye nohlobo lwe-adsorbent. Uluhlu lweqondo lobushushu elingaguqukiyo lwe-170-315oC (338-600oF) luya kufuneka kwiindidi zezisefu ezixoxwe ngaphambili. Zombini izinto ezibhengezwayo, kwaye i-adsorbent ifudunyezwa kulo bushushu. Ukomisa ngevacuum yindlela ekhawulezayo yokwenza oku kwaye kufuna amaqondo obushushu asezantsi xa kuthelekiswa nokomisa amadangatye.

Nje ukuba isebenze, iisefu zinokugcinwa kwisitya seglasi kunye neparafilm esongelwe kabini. Oku kuya kuzigcina zisebenza ukuya kutsho kwiinyanga ezintandathu. Ukujonga ukuba iisefu ziyasebenza, ungazibamba ngesandla ngelixa unxibe iiglavu kwaye wongeze amanzi kuzo. Ukuba zisebenza ngokupheleleyo, ke ukushisa kuphakama kakhulu, kwaye awuyi kukwazi ukuzibamba nangona unxibe iiglavu.

Ukusetyenziswa kwezixhobo zokhuseleko ezifana neekhithi zePPE, iiglavu, kunye neeglasi zokhuseleko kuyacetyiswa njengoko inkqubo yokuvula isisefu semolekyuli ibandakanya ukujongana namaqondo obushushu aphezulu kunye neekhemikhali, kunye neengozi ezinxulumene noko.