Sefa ya molekyulu ndi chinthu chokhala ndi mabowo (mabowo ang'onoang'ono kwambiri) ofanana kukula

Sefa ya molekyulu ndi chinthu chokhala ndi ma pores (mabowo ang'onoang'ono kwambiri) ofanana kukula. Ma pores awa ali ndi kukula kofanana ndi mamolekyu ang'onoang'ono, motero mamolekyu akuluakulu sangalowe kapena kulowetsedwa, pomwe mamolekyu ang'onoang'ono amatha. Pamene chisakanizo cha mamolekyulu chimasuntha kudzera mu bedi losasunthika la chinthu chopanda madzi, chotchedwa semi-solid pores (kapena matrix), zigawo za kulemera kwakukulu kwa molekyulu (zomwe sizingathe kudutsa mu ma pores a molekyulu) zimachoka pabedi kaye, kutsatiridwa ndi mamolekyu ang'onoang'ono motsatizana. Ma sefa ena a molekyulu amagwiritsidwa ntchito mu chromatography ya kukula-kupatula, njira yolekanitsira yomwe imasankha mamolekyu kutengera kukula kwawo. Ma sefa ena a molekyulu amagwiritsidwa ntchito ngati desiccants (zina mwa zitsanzo zikuphatikizapo makala ogwiritsidwa ntchito ndi silica gel).
M'mimba mwake mwa pore ya sieve ya molecular imayesedwa mu ångströms (Å) kapena nanometers (nm). Malinga ndi IUPAC notation, zinthu zokhala ndi pore yaying'ono zimakhala ndi ma pore diameter ochepera 2 nm (20 Å) ndipo zinthu zokhala ndi pore yaying'ono zimakhala ndi ma pore diameter opitilira 50 nm (500 Å); motero gulu la mesoporous lili pakati pomwe ma pore diameter ali pakati pa 2 ndi 50 nm (20–500 Å).
Zipangizo
Masefa a mamolekyu amatha kukhala opangidwa ndi ma microporous, mesoporous, kapena macroporous.
Zinthu zokhala ndi ma micropore (
●Zeolites (mchere wa aluminosilicate, osati wosakanikirana ndi aluminiyamu silicate)
●Zeolite LTA: 3–4 Å
●Galasi lokhala ndi mabowo: 10 Å (1 nm), ndi mmwamba
●Kaboni yogwira ntchito: 0–20 Å (0–2 nm), ndi mmwamba
● Dongo
● Zosakaniza za Montmorillonite
●Halloysite (endellite): Mitundu iwiri yofanana imapezeka, dongo likasungunuka limakhala ndi mtunda wa 1 nm pakati pa zigawo ndipo likasungunuka (meta-halloysite) mtunda wake ndi 0.7 nm. Halloysite mwachibadwa imapezeka ngati masilinda ang'onoang'ono omwe ali ndi mainchesi a 30 nm m'mimba mwake okhala ndi kutalika pakati pa 0.5 ndi 10 micrometers.
Zinthu zopingasa (2–50 nm)
Silicon dioxide (yogwiritsidwa ntchito popanga silica gel): 24 Å (2.4 nm)
Zinthu zokhala ndi mapopoma akuluakulu (>50 nm)
Silica yokhala ndi mapopo ambiri, 200–1000 Å (20–100 nm)
Mapulogalamu[sintha]
Ma sieve a molecular nthawi zambiri amagwiritsidwa ntchito mumakampani opanga mafuta, makamaka poumitsa mitsinje ya gasi. Mwachitsanzo, mumakampani opanga gasi wachilengedwe wamadzimadzi (LNG), kuchuluka kwa madzi mu gasi kuyenera kuchepetsedwa kufika pa 1 ppmv kuti kupewe kutsekeka komwe kumachitika chifukwa cha ayezi kapena methane clathrate.
Mu labotale, ma sefa a molecular amagwiritsidwa ntchito kuumitsa solvent. "Ma sefa" atsimikiziridwa kuti ndi apamwamba kuposa njira zachikhalidwe zowumitsira, zomwe nthawi zambiri zimagwiritsa ntchito mankhwala oletsa kutupa.
Pansi pa mawu akuti zeolites, ma molecular sieves amagwiritsidwa ntchito pazinthu zosiyanasiyana zoyambitsa zinthu. Amathandizira isomerization, alkylation, ndi epoxidation, ndipo amagwiritsidwa ntchito m'mafakitale akuluakulu, kuphatikizapo hydrocracking ndi fluid catalytic cracking.
Amagwiritsidwanso ntchito posefa mpweya wa zipangizo zopumira, mwachitsanzo zomwe zimagwiritsidwa ntchito ndi osambira m'madzi ndi ozimitsa moto. Mu ntchito zotere, mpweya umaperekedwa ndi compressor ya mpweya ndipo umadutsa mu fyuluta ya cartridge yomwe, kutengera momwe imagwiritsidwira ntchito, imadzazidwa ndi sieve ya molecular ndi/kapena activated carbon, pamapeto pake imagwiritsidwa ntchito kuyitanitsa matanki a mpweya wopumira. Kusefa kotereku kumatha kuchotsa tinthu tating'onoting'ono ndi zinthu zotulutsa mpweya wa compressor kuchokera ku mpweya wopumira.
Kuvomerezedwa ndi FDA.
Bungwe la US FDA kuyambira pa Epulo 1, 2012, lavomereza sodium aluminosilicate kuti igwirizane mwachindunji ndi zinthu zomwe zingagwiritsidwe ntchito pansi pa 21 CFR 182.2727. Asanavomereze izi, European Union idagwiritsa ntchito ma molecular seeves okhala ndi mankhwala ndipo mayeso odziyimira pawokha adawonetsa kuti ma molecular seeves akukwaniritsa zofunikira zonse za boma koma makampaniwa sanafune kulipira ndalama zoyesera zokwera mtengo zomwe zimafunikira kuti boma livomereze.
Kubadwanso
Njira zobwezeretsera ma sieve a mamolekyulu ndi monga kusintha kwa kuthamanga kwa mpweya (monga momwe zimakhalira ndi okosijeni), kutentha ndi kutsuka ndi mpweya wonyamula (monga momwe zimagwiritsidwira ntchito mu ethanol dehydration), kapena kutentha pansi pa vacuum cleaner yapamwamba. Kutentha kwa kubwezeretsa kumakhala kuyambira 175 °C (350 °F) mpaka 315 °C (600 °F) kutengera mtundu wa sieve ya mamolekyulu. Mosiyana ndi zimenezi, silica gel ikhoza kubwezeretsedwanso mwa kuitentha mu uvuni wamba mpaka 120 °C (250 °F) kwa maola awiri. Komabe, mitundu ina ya silica gel "imatuluka" ikakumana ndi madzi okwanira. Izi zimachitika chifukwa cha kusweka kwa ma sieve a silica ikakhudzana ndi madzi.

Chitsanzo	Chidutswa cha m'mimba mwake (Ångström)	Kuchuluka kwa zinthu (g/ml)	Madzi osungunuka (% w/w)	Kuchepa kapena kusweka, W(% w/w)	Kagwiritsidwe Ntchito
3Å	3	0.60–0.68	19–20	0.3–0.6	Kuchotsa madzi m'thupiyakusweka kwa mafutampweya ndi alkenes, kusankha kwa H2O mugalasi lotetezedwa (IG)ndi polyurethane, kuumitsa kwamafuta a ethanolkuti musakanize ndi mafuta.
4Å	4	0.60–0.65	20–21	0.3–0.6	Kulowetsedwa kwa madzi musodium aluminosilicatezomwe zavomerezedwa ndi FDA (onanipansipa) amagwiritsidwa ntchito ngati sefa ya molekyulu m'zidebe zachipatala kuti zomwe zili mkati zikhale zouma komanso ngatichowonjezera chakudyakukhala ndiNambala ya EE-554 (choletsa kutsekeka); Chogwiritsidwa ntchito kwambiri pochotsa madzi m'madzi otsekedwa kapena mpweya, mwachitsanzo, m'mabokosi a mankhwala, zida zamagetsi ndi mankhwala omwe amatha kuwonongeka; kuchotsa madzi m'makina osindikizira ndi mapulasitiki komanso kuumitsa mitsinje ya hydrocarbon yokhuta. Mitundu yomwe imakhudzidwa ndi madzi ndi monga SO2, CO2, H2S, C2H4, C2H6, ndi C3H6. Kawirikawiri imaonedwa kuti ndi yowumitsa yonse m'malo ozungulira komanso osazungulira;[12]kulekanitsidwa kwagasi wachilengedwendialkeneskuyamwa kwa madzi m'malo omwe sakhudzidwa ndi nayitrogenipolyurethane
5Å-DW	5	0.45–0.50	21–22	0.3–0.6	Kuchepetsa mafuta ndi kutsitsa kwa pour pointndege palafinindidizilo, ndi kulekanitsa kwa alkenes
5Å wolemera mpweya pang'ono	5	0.4–0.8	≥23		Yopangidwira makamaka makina opangira mpweya wa okosijeni m'zachipatala kapena wathanzi [kufunikira kwa mawu]
5Å	5	0.60–0.65	20–21	0.3–0.5	Kuchotsa mpweya m'thupi ndi kuuyeretsa;kutaya madzi m'thupindikuchotsedwa kwa sulfuregasi wachilengedwe ndimpweya wamafuta amadzimadzi;mpweyandihaidrojenikupanga ndikukakamiza kugwedezekanjira
10X	8	0.50–0.60	23–24	0.3–0.6	Kusungunula bwino kwambiri, komwe kumagwiritsidwa ntchito pochotsa mpweya m'thupi, kuchotsa poizoni m'thupi, kuchotsa sulfur mu mpweya ndi zakumwa komanso kulekanitsa mpweya ndi madzi.hydrocarbon yonunkhira
13X	10	0.55–0.65	23–24	0.3–0.5	Kuchotsa mpweya wa mafuta ndi gasi wachilengedwe m'thupi, kuchotsa sulfure m'thupi ndi kuyeretsa mpweya wa mafuta ndi gasi wachilengedwe
13X-AS	10	0.55–0.65	23–24	0.3–0.5	Kuchotsa kabotolo m'thupindi kuuma kwa mpweya m'makampani olekanitsa mpweya, kulekanitsa nayitrogeni ndi mpweya m'mafakitale osungira mpweya
Cu-13X	10	0.50–0.60	23–24	0.3–0.5	Kutsekemera(kuchotsedwa kwathiols) yamafuta a ndegendi zofananama hydrocarbon amadzimadzi

Mphamvu zokoka

3Å

Fomula yoyerekeza ya mankhwala: ((K2O)2⁄3 (Na2O)1⁄3) • Al2O3• 2 SiO2 • 9/2 H2O

Chiŵerengero cha silika-alumina: SiO2/ Al2O3≈2

Kupanga

3Ma sieve a molecular amapangidwa ndi kusinthana kwa cationpotaziyamuchifukwa chasodiummu ma sefa a 4A molecular (Onani pansipa)

Kagwiritsidwe Ntchito

Ma sieve a mamolekyulu a 3Å samatenga mamolekyulu omwe mainchesi ake ndi akulu kuposa 3Å. Makhalidwe a ma sieve a mamolekyulu awa ndi monga kuthamanga kwa madzi mwachangu, kuthekera kobwezeretsa zinthu pafupipafupi, kukana kuphwanya bwino komansokukana kuipitsidwa kwa mpweyaZinthu zimenezi zimatha kukonza bwino ntchito ya sefa komanso moyo wake wonse. Ma sefa a 3Å molecular ndi ofunikira kwambiri m'mafakitale a mafuta ndi mankhwala poyenga mafuta, polymerization, komanso kuumitsa kuya kwa gasi ndi madzi pogwiritsa ntchito mankhwala.

Ma sieve a 3Å molecular amagwiritsidwa ntchito kuumitsa zinthu zosiyanasiyana, mongaethanol, mpweya,zoziziritsira,gasi wachilengedwendima hydrocarbon osakhutaZomalizazi zikuphatikizapo mpweya wosweka,asetilini,ethylene,propylenendibutadiene.

Sipo ya 3Å molecular imagwiritsidwa ntchito kuchotsa madzi mu ethanol, omwe pambuyo pake angagwiritsidwe ntchito mwachindunji ngati bio-fuel kapena mwanjira ina kupanga zinthu zosiyanasiyana monga mankhwala, zakudya, mankhwala, ndi zina. Popeza kusungunuka kwabwinobwino sikungachotse madzi onse (chomwe sichingachitike kuchokera ku kupanga ethanol) kuchokera ku njira ya ethanol chifukwa cha kupangika kwaazeotropePa kulemera kwa pafupifupi 95.6 peresenti, mikanda yosefera ya molekyulu imagwiritsidwa ntchito kulekanitsa ethanol ndi madzi pamlingo wa molekyulu mwa kulowetsa madzi mu mikanda ndikulola ethanol kudutsa momasuka. Mikanda ikadzaza ndi madzi, kutentha kapena kupanikizika kumatha kusinthidwa, zomwe zimathandiza kuti madzi atuluke mu mikanda yosefera ya molekyulu.[15]

Ma sieve a 3Å molecular amasungidwa kutentha kwa chipinda, ndi chinyezi chosapitirira 90%. Amatsekedwa pansi pa kupsinjika kochepa, ndipo amasungidwa kutali ndi madzi, ma acid ndi alkali.

4Å

Fomula ya mankhwala: Na2O•Al2O3•2SiO2•9/2H2O

Chiŵerengero cha silicon-aluminium: 1:1 (SiO2/ Al2O3≈2)

Kupanga

Kupanga sieve ya 4Å ndikosavuta chifukwa sikumafuna kupanikizika kwambiri kapena kutentha kwambiri. Kawirikawiri madzi amadzimadzi asodium silicatendisodium aluminatezimasakanizidwa pa 80 °C. Chosakaniza chosungunukacho chimayatsidwa "pophika" pa 400 °C. Ma sefa a 4A amagwira ntchito ngati choyambira cha ma sefa a 3A ndi 5A kudzerakusinthana kwa cationyasodiumchifukwa chapotaziyamu(kwa 3A) kapenakashiamu(kwa 5A)

Kagwiritsidwe Ntchito

Zosungunulira zouma

Ma sieve a 4Å molecular amagwiritsidwa ntchito kwambiri poumitsa zosungunulira za m'ma laboratories. Amatha kuyamwa madzi ndi mamolekyu ena okhala ndi mainchesi ochepera 4 Å monga NH3, H2S, SO2, CO2, C2H5OH, C2H6, ndi C2H4. Amagwiritsidwa ntchito kwambiri pakuumitsa, kuyeretsa ndi kuyeretsa zakumwa ndi mpweya (monga kukonzekera argon).

 

Zowonjezera za poliyesitala [sintha]

Masefa a molekyu awa amagwiritsidwa ntchito kuthandiza sopo chifukwa amatha kutulutsa madzi opanda mchere kudzera mukashiamukusinthana kwa ayoni, kuchotsa ndikuletsa kuti dothi lisalowe. Amagwiritsidwa ntchito kwambiri m'malo mwakephosphorousSieve ya 4Å molecular imagwira ntchito yofunika kwambiri m'malo mwa sodium tripolyphosphate ngati sopo wothandizira kuti ichepetse kuwonongeka kwa sopo. Ingagwiritsidwenso ntchito ngati chotsukirasopowothandizira kupanga ndimankhwala otsukira mano.

Kuchiza zinyalala zoopsa

Ma sieve a 4Å molecular amatha kuyeretsa zinyalala za mitundu ya cationic mongaammoniamuma ion, Pb2+, Cu2+, Zn2+ ndi Cd2+. Chifukwa cha kusankha kwakukulu kwa NH4+ agwiritsidwa ntchito bwino pankhondoeutrophicationndi zotsatira zina m'misewu yamadzi chifukwa cha kuchuluka kwa ma ayoni a ammonium. Ma sieve a 4Å molecular agwiritsidwanso ntchito kuchotsa ma ayoni achitsulo cholemera omwe amapezeka m'madzi chifukwa cha ntchito zamafakitale.

Zolinga zina

Themakampani opanga zitsulo: cholekanitsa, kulekanitsa, kuchotsa potaziyamu wamadzi amchere,rubidium,cesium, ndi zina zotero.

Makampani opanga mafuta,chothandizira,chotsukira mano, chokometsera

Ulimi:chowongolera nthaka

Mankhwala: siliva wolemerazeolitewothandizira antibacterial.

5Å

Fomula ya mankhwala: 0.7CaO•0.30Na2O•Al2O3•2.0SiO2 •4.5H2O

Chiŵerengero cha silika-alumina: SiO2/ Al2O3≈2

Kupanga

5Ma sieve a molecular amapangidwa ndi kusinthana kwa cationkashiamuchifukwa chasodiummu ma sefa a mamolekyulu a 4A (Onani pamwambapa)

Kagwiritsidwe Ntchito

Zisanu-ångström(5Å) ma sefa a mamolekyu nthawi zambiri amagwiritsidwa ntchito mumafutamafakitale, makamaka poyeretsa mitsinje ya gasi komanso mu labotale ya chemistry yolekanitsamankhwalandi zinthu zoyambira zoyatsira mpweya. Zili ndi ma pores ang'onoang'ono a kukula kolondola komanso kofanana, ndipo zimagwiritsidwa ntchito makamaka ngati chokometsera mpweya ndi zakumwa.

Ma sieve a mamolekyu asanu a ångström amagwiritsidwa ntchito poumitsagasi wachilengedwe, pamodzi ndi kuchitakuchotsedwa kwa sulfurendikuchotsa mpweya m'thupiAngagwiritsidwenso ntchito kulekanitsa zosakaniza za mpweya, nayitrogeni ndi haidrojeni, ndi mafuta-wax n-hydrocarbons kuchokera ku ma hydrocarbons opangidwa ndi nthambi ndi polycyclic.

Ma sieve a mamolekyu asanu a ångström amasungidwa kutentha kwa chipinda, ndichinyezi chaching'onozosakwana 90% m'migolo ya makatoni kapena m'mabokosi. Ma sefa a molekyulu sayenera kuwonetsedwa mwachindunji ku mpweya ndi madzi, ma acid ndi ma alkali ayenera kupewedwa.

Maonekedwe a ma sieve a mamolekyulu

Masefa a mamolekyu amapezeka m'mawonekedwe ndi kukula kosiyanasiyana. Koma mikanda yozungulira ili ndi ubwino kuposa mawonekedwe ena chifukwa imapereka kutsika pang'ono kwa kupanikizika, imapirira kutsika chifukwa ilibe m'mbali zakuthwa, ndipo ili ndi mphamvu yabwino, mwachitsanzo mphamvu yophwanyika yomwe imafunika pa gawo lililonse ndi yayikulu. Masefa ena a mamolekyu okhala ndi mikanda amapereka mphamvu yochepa yotentha motero amafunikira mphamvu zochepa panthawi yokonzanso.

Ubwino wina wogwiritsa ntchito ma sieve a molecular okhala ndi mikanda ndi wakuti kuchuluka kwa zinthu nthawi zambiri kumakhala kokwera kuposa mawonekedwe ena, motero kuti pakhale kulowetsedwa komweko, kuchuluka kwa ma sieve a molecular ndikofunikira. Chifukwa chake, mukachotsa botolo, munthu angagwiritse ntchito ma sieve a molecular okhala ndi mikanda, kuyika zinthu zambiri zolowetsedwa mu voliyumu yomweyo, ndikupewa kusintha kulikonse kwa mitsempha yamagazi.