Inkcazo
Iimolekyuli zezinto ezahlukeneyo zihlukaniswa ngokubaluleka kunye nobukhulu be-adsorption, ngoko umfanekiso ubizwa ngokuba yi "molecular sieve".
I-molecular sieve (eyaziwa ngokuba yi-synthetic zeolite) yikristale ye-silicate microporous.Isiseko se-skeleton isakhiwo esakhiwe nge-silicon aluminate, kunye ne-cations zetsimbi (ezifana ne-Na +, K +, Ca2 +, njl.) ukulungelelanisa umrhumo ogqithisileyo ongalunganga kwikristale.Uhlobo lwe-molecular sieve luhlulwe kakhulu lube yi-A, uhlobo lwe-X kunye nohlobo lwe-Y ngokwesakhiwo sekristale.
| Ifomula yekhemikhali yeeseli ze-zeolite: | Mx/n [(AlO.2) x (SiO.2) y]WH.2O. |
| Mx/n:. | I-Cation ion, ukugcina ikristale yombane ingathathi hlangothi |
| (AlO2) x (SiO2) y: | I-skeleton yeekristale ze-zeolite, ezinemilo eyahlukeneyo yemingxuma kunye nemijelo |
| H2O: | umphunga wamanzi adsorbed ngokwasemzimbeni |
| Iimbonakalo: | I-adsorption eninzi kunye ne-desorption inokwenziwa |
| Chwetheza iSieve yeMolekyuli | Inxalenye ephambili yohlobo lwe-A molecular sieve yi-silicon aluminate. Umngxuma oyintloko wekristale yisakhiwo se-octaring.I-aperture ye-crystal aperture enkulu yi-4Å(1Å=10-10m), eyaziwa ngokuba yi-type 4A (eyaziwa nangokuthi uhlobo A) i-molecular sieve;
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| Uhlobo X lweSieve yeMolekyuli | Inxalenye ephambili ye-X ye-molecular sieve yi-silicon aluminate, owona mngxuma wekristale oyintloko yi-12 element element ring. I-Ca2 + yatshintshwa nge-Na + kwi-13X ye-molecular sieve, yenza i-crystal sieve ye-molecular ene-aperture ye-8-9 A, ebizwa ngokuba yi-10X (eyaziwa nangokuthi i-calcium X) i-molecular sieve.
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Chwetheza iSieve yeMolekyuli
Uhlobo X lweSieve yeMolekyuli
Isicelo
I-adsorption yezinto eziphathekayo ivela kwi-adsorption ebonakalayo (i-vander Waals Force), ene-polarity eyomeleleyo kunye namasimi e-Coulomb ngaphakathi komngxuma wayo wekristale, ebonisa amandla e-adsorption anamandla kwiimolekyuli ze-polar (ezifana namanzi) kunye neemolekyuli ezingaxutywanga.
Ukuhanjiswa kwe-aperture ye-sieve ye-molecular ifana kakhulu, kwaye kuphela izinto ezinobubanzi be-molecular encinci kunobubanzi bomngxuma onokungena kumngxuma wekristale ngaphakathi kwe-molecular sieve.