Siffar kwayoyin halitta abu ne mai pores (kananan ramuka sosai) na girman iri ɗaya. Waɗannan diamita na pore suna kama da girman ƙananan ƙwayoyin cuta, don haka manyan ƙwayoyin cuta ba za su iya shiga ko a haɗa su ba, yayin da ƙananan ƙwayoyin cuta za su iya. Kamar yadda cakuda kwayoyin halitta ke ƙaura ta cikin gadon tsaye na porous, abu mai ƙarfi wanda ake magana da shi azaman sieve (ko matrix), abubuwan da ke cikin mafi girman nauyin kwayoyin (waɗanda ba su iya shiga cikin ramukan ƙwayoyin cuta) barin gadon farko, biye da ƙananan ƙananan ƙwayoyin cuta. Ana amfani da wasu sieves na ƙwayoyin cuta a cikin chromatography mai girma, dabarar rabuwa da ke rarraba kwayoyin dangane da girmansu. Ana amfani da sauran sieves na kwayoyin azaman masu bushewa (wasu misalan sun haɗa da gawayi da aka kunna da gel silica).
Ana auna diamita na ramukan ramukan ƙwayoyin cuta a ångströms (Å) ko nanometers (nm). Dangane da bayanin IUPAC, kayan microporous suna da diamita na pore na ƙasa da 2 nm (20 Å) kuma kayan macroporous suna da diamita na pore fiye da 50 nm (500 Å); Rukunin mesoporous don haka ya ta'allaka ne a tsakiya tare da diamita na pore tsakanin 2 da 50 nm (20-500 Å).
Kayayyaki
Sives na kwayoyin halitta na iya zama microporous, mesoporous, ko macroporous abu.
Microporous abu (
● Zeolites (ma'adinan aluminosilicate, kada a rikita batun tare da silicate na aluminum)
●Zeolite LTA: 3-4 Å
● Gilashin mai ƙarfi: 10 Å (1 nm), kuma sama
● Carbon mai aiki: 0-20 Å (0-2 nm), da sama
●Lalle
●Montmorillonite intermixes
●Halloysite (endellite): Ana samun nau'i biyu na yau da kullum, lokacin da ruwa ya cika yumbu yana nuna tazarar 1 nm na yadudduka kuma lokacin da aka bushe (meta-halloysite) tazarar shine 0.7 nm. Halloysite a dabi'a yana faruwa azaman ƙananan silinda waɗanda matsakaicin 30 nm a diamita tare da tsayi tsakanin 0.5 zuwa 10 micrometers.
Mesoporous abu (2-50 nm)
Silicon dioxide (amfani da silica gel): 24 Å (2.4 nm)
Macroporous abu (> 50 nm)
Silica macroporous, 200-1000 Å (20-100 nm)
Aikace-aikace[gyara gyara]
Yawanci ana amfani da sieve na ƙwayoyin cuta a cikin masana'antar mai, musamman don bushewar magudanan iskar gas. Misali, a masana'antar iskar gas ta ruwa (LNG), ana buƙatar rage yawan ruwan iskar zuwa ƙasa da 1 ppmv don hana toshewar ƙanƙara ko methane clathrate.
A cikin dakin gwaje-gwaje, ana amfani da sieves na kwayoyin halitta don bushewa da sauran ƙarfi. "Sieves" sun tabbatar da sun fi na'urorin bushewa na gargajiya, waɗanda galibi suna amfani da masu bushewa.
A ƙarƙashin kalmar zeolites, ana amfani da sieves na ƙwayoyin cuta don aikace-aikace masu yawa na catalytic. Suna haifar da isomerisation, alkylation, da epioxidation, kuma ana amfani da su a cikin manyan matakan masana'antu, ciki har da hydrocracking da fashewar catalytic ruwa.
Ana kuma amfani da su wajen tace kayayyakin da ake amfani da su na iska don na'urorin numfashi, misali wadanda masu ruwa da tsaki da masu kashe gobara ke amfani da su. A cikin irin waɗannan aikace-aikacen, ana ba da iska ta hanyar kwampreso na iska kuma an wuce ta cikin matattarar harsashi wanda, dangane da aikace-aikacen, an cika shi da sieve na kwayoyin halitta da / ko carbon da aka kunna, a ƙarshe ana amfani dashi don cajin tankunan iska. Irin wannan tacewa zai iya cire ɓarna. da kwampreso shaye kayayyakin daga numfashi samar da iska.
Amincewar FDA.
FDA ta Amurka tun daga Afrilu 1, 2012, ta amince da sodium aluminosilicate don saduwa da kai tsaye tare da abubuwan da ake amfani da su a ƙarƙashin 21 CFR 182.2727. Kafin wannan amincewa Tarayyar Turai ta yi amfani da sieves na ƙwayoyin cuta tare da magunguna da gwaje-gwaje masu zaman kansu sun nuna cewa sieves na ƙwayoyin cuta sun cika duk buƙatun gwamnati amma masana'antar ta kasance ba ta son bayar da kuɗin gwajin tsadar da ake buƙata don amincewar gwamnati.
Farfadowa
Hanyoyi don sake farfado da sieves na kwayoyin sun hada da canjin matsa lamba (kamar yadda yake a cikin masu tattara iskar oxygen), dumama da tsaftacewa tare da iskar gas (kamar lokacin da aka yi amfani da shi a cikin rashin ruwa na ethanol), ko dumama a ƙarƙashin babban injin. Zazzabi na sabuntawa yana daga 175 °C (350 °F) zuwa 315 °C (600 °F) dangane da nau'in sieve kwayoyin. Akasin haka, za a iya sabunta gel ɗin silica ta hanyar dumama shi a cikin tanda na yau da kullun zuwa 120 ° C (250 ° F) na sa'o'i biyu. Duk da haka, wasu nau'ikan gel na silica za su "pop" lokacin da aka fallasa su zuwa isasshen ruwa. Wannan yana faruwa ne ta hanyar karyewar sassan siliki lokacin da ake tuntuɓar ruwan.
| Samfura | Diamita na Pore (Ångström) | Yawan yawa (g/ml) | Ruwan da aka sha (% w/w) | Amfani | |
| 3Å | 3 | 0.60-0.68 | 19-20 | 0.3-0.6 | Desiccationnafasa man feturgas da alkenes, zaɓin adsorption na H2O inGilashin da aka keɓe (IG)da polyurethane, bushewa naman fetur ethanoldomin hadawa da fetur. |
| 4Å | 4 | 0.60-0.65 | 20-21 | 0.3-0.6 | Adsorption na ruwa a cikisodium aluminosilicatewanda FDA ta amince (dubakasa) ana amfani da shi azaman sieve na ƙwayoyin cuta a cikin kwantena na likitanci don kiyaye abun ciki bushe da kamar yaddaabinci karisamunE-lambaE-554 (wakilin anti-caking); An fi so don bushewar ruwa a cikin rufaffiyar ruwa ko tsarin gas, misali, a cikin marufi na magunguna, abubuwan lantarki da sinadarai masu lalacewa; tarwatsa ruwa a cikin tsarin bugu da robobi da bushewa cikakkun rafukan ruwa na hydrocarbon. Dabbobin da aka yi wa ado sun haɗa da SO2, CO2, H2S, C2H4, C2H6, da C3H6. Gabaɗaya ana la'akari da wakili na bushewa na duniya a cikin kafofin watsa labarai na polar da marasa ƙarfi;[12]rabuwa daiskar gaskumaalkenes, adsorption na ruwa a cikin marasa amfani da nitrogenpolyurethane |
| 5A-DW | 5 | 0.45-0.50 | 21-22 | 0.3-0.6 | Degreeasing da zuba batu ciki najirgin sama kananzirkumadizal, da kuma rabuwar alkenes |
| 5Å ƙananan wadataccen iskar oxygen | 5 | 0.4-0.8 | ≥23 | An ƙirƙira shi musamman don ingantacciyar iskar oxygen ko lafiya.abin da ake bukata] | |
| 5Å | 5 | 0.60-0.65 | 20-21 | 0.3-0.5 | Desiccation da tsarkakewar iska;rashin ruwakumadesulfurizationna iskar gas da kumaiskar gas mai ruwa;oxygenkumahydrogensamarwa tamatsa lamba lilo adsorptiontsari |
| 10X | 8 | 0.50-0.60 | 23–24 | 0.3-0.6 | High-inganci sorption, amfani da desiccation, decarburization, desulfurization na gas da taya da kuma rabuwa daaromatic hydrocarbon |
| 13X | 10 | 0.55-0.65 | 23–24 | 0.3-0.5 | Desiccation, desulfurization da tsarkakewa na man fetur da kuma iskar gas |
| 13X-AS | 10 | 0.55-0.65 | 23–24 | 0.3-0.5 | Decarburizationda desiccation a cikin iska rabuwa masana'antu, rabuwa da nitrogen daga oxygen a cikin oxygen concentrators |
| Ku-13X | 10 | 0.50-0.60 | 23–24 | 0.3-0.5 | Zaƙi(cirethiols) naman jirgin samakuma masu dacewaruwa hydrocarbons |
Adsorption damar
3Å
Kimanta dabarar sinadarai: ((K2O)2⁄3 (Na2O)1⁄3) • Al2O3• 2 SiO2 • 9/2 H2O
Silica-alumina rabo: SiO2/ Al2O3≈2
Production
Ana samar da sieves guda 3 ta hanyar musayar cation napotassiumdominsodiuma cikin sieves kwayoyin 4A (Duba ƙasa)
Amfani
3Å sieves na kwayoyin ba sa adsorb kwayoyin da diamita ya fi 3 Å girma. Halayen waɗannan sieves na kwayoyin sun haɗa da saurin adsorption da sauri, ƙarfin sake haɓakawa akai-akai, juriya mai kyau da juriyajuriya gurbacewar yanayi. Waɗannan fasalulluka na iya haɓaka duka inganci da rayuwar sieve. 3Å kwayoyin sieves sune maƙasudin da ake buƙata a cikin masana'antar mai da sinadarai don tace mai, polymerization, da bushewar zurfin ruwa mai guba.
Ana amfani da sieves na kwayoyin 3Å don bushe nau'ikan kayan aiki, kamarethanol, iska,firiji,iskar gaskumaunsaturated hydrocarbons. Na ƙarshe sun haɗa da fashewar gas,acetylene,ethylene,propylenekumabutadiene.
Ana amfani da sieve na 3Å don cire ruwa daga ethanol, wanda daga baya za'a iya amfani dashi kai tsaye azaman man fetur ko a kaikaice don samar da kayayyaki daban-daban kamar sinadarai, abinci, magunguna, da sauransu. Tun da distillation na al'ada ba zai iya cire duk ruwa ba (wani samfurin da ba a so daga samar da ethanol) daga kogunan tsarin ethanol saboda samuwarazeotropea kusan kashi 95.6 cikin ɗari ta nauyi, ana amfani da beads sieve na ƙwayoyin cuta don raba ethanol da ruwa akan matakin kwayoyin ta hanyar adsorbing ruwan a cikin beads da barin ethanol ya wuce cikin yardar kaina. Da zarar beads sun cika da ruwa, za a iya sarrafa zafin jiki ko matsa lamba, wanda zai ba da damar fitar da ruwan daga beads sieve na kwayoyin.[15]
Ana adana sieves na kwayoyin 3Å a cikin zafin jiki, tare da danshi mai dangi bai wuce 90%. An rufe su a ƙarƙashin rage matsa lamba, ana kiyaye su daga ruwa, acid da alkalis.
4Å
Tsarin sinadaran: Na2O•Al2O3•2SiO2•9/2H2O
Silicon-aluminium rabo: 1: 1 (SiO2 / Al2O3≈2)
Production
Samar da sieve 4Å yana da sauƙi a sauƙaƙe saboda baya buƙatar matsa lamba ko musamman yanayin zafi. Yawanci maganin ruwa nasodium silicatekumasodium aluminumana haɗe su a 80 ° C. Ana "kunna" samfurin da aka yi ciki ta hanyar "yin burodi" a 400 ° C 4A sieves suna aiki a matsayin maƙasudin zuwa 3A da 5A sieves ta hanyar.musayar canjinasodiumdominpotassium(na 3A) kocalcium(na 5A)
Amfani
Abubuwan bushewa
Ana amfani da sieves na kwayoyin 4Å don busar da kaushi na dakin gwaje-gwaje. Za su iya sha ruwa da sauran kwayoyin halitta tare da diamita mai mahimmanci kasa da 4 Å kamar NH3, H2S, SO2, CO2, C2H5OH, C2H6, da C2H4. Ana amfani da su sosai a cikin bushewa, tsaftacewa da tsarkakewa na ruwa da gas (kamar shirye-shiryen argon).
Polyester Additivesgyara]
Ana amfani da waɗannan sieve na ƙwayoyin cuta don taimakawa kayan wanka saboda suna iya samar da ruwan da aka lalatar da sucalciummusanya ion, cirewa da hana shigar da datti. Ana amfani da su sosai don maye gurbinphosphorus. 4Å molecular sieve yana taka muhimmiyar rawa don maye gurbin sodium tripolyphosphate a matsayin kayan taimako na wanka don rage tasirin muhalli na wanki. Hakanan za'a iya amfani dashi azaman asabulukafa wakili da kuma aman goge baki.
Magani mai cutarwa
4Å kwayoyin sieves iya tsarkake najasa na cationic jinsunan kamarammoniumions, Pb2+, Cu2+, Zn2+ da Cd2+. Saboda babban zaɓi na NH4+ an yi nasarar amfani da su a fagen famaeutrophicationda sauran illolin a cikin hanyoyin ruwa saboda yawan ion ammonium. An kuma yi amfani da sieves na kwayoyin 4Å don cire ions masu nauyi da ke cikin ruwa saboda ayyukan masana'antu.
Wasu dalilai
Themasana'antar karafa: separating wakili, rabuwa, hakar na brine potassium,rubidium,cesium, da dai sauransu.
Masana'antar Petrochemical,mai kara kuzari,desiccant, adsorbent
Noma:kasa kwandishan
Magunguna: lodin azurfazeoliteantibacterial wakili.
5Å
Tsarin sinadaran: 0.7CaO•0.30Na2O•Al2O3•2.0SiO2 •4.5H2O
Silica-alumina rabo: SiO2/ Al2O3≈2
Production
Ana samar da sieves na kwayoyin ta hanyar musayar cation nacalciumdominsodiuma cikin sieves kwayoyin halitta 4A (Duba sama)
Amfani
Biyar-angström(5Å) ana yawan amfani da sieves na ƙwayoyin cuta a cikinman feturmasana'antu, musamman don tsarkake rafukan iskar gas da kuma a cikin dakin gwaje-gwajen sunadarai don rabuwamahadida bushewa dauki fara kayan. Suna ƙunshe da ƙananan ƙofofi masu daidaici kuma girman iri ɗaya, kuma galibi ana amfani da su azaman abin tallatawa ga gas da ruwaye.
Ana amfani da sieves na kwayoyin halitta biyar-ångström don bushewaiskar gas, tare da yin aikidesulfurizationkumadecarbonationna gas. Hakanan za'a iya amfani da su don ware cakuda oxygen, nitrogen da hydrogen, da n-hydrocarbons mai-kakin mai daga rassa da hydrocarbons na polycyclic.
Biyar-ångström kwayoyin sieves ana adana su a dakin da zafin jiki, tare da adangi zafikasa da 90% a cikin ganga na kwali ko kwalin kwali. Bai kamata a baje kolin kwayoyin halitta kai tsaye zuwa iska da ruwa ba, ya kamata a guji acid da alkalis.
Ilimin ilimin halittar jiki na sieves na kwayoyin halitta
Siffofin kwayoyin halitta suna samuwa a cikin nau'i daban-daban da girma dabam. Amma spherical beads suna da fa'ida fiye da sauran siffofi yayin da suke bayar da raguwar matsa lamba, suna da juriya saboda ba su da wani gefuna masu kaifi, kuma suna da ƙarfi mai kyau, watau murkushe ƙarfin da ake buƙata kowane yanki ya fi girma. Wasu ƙwanƙwaran ƙwayoyin ƙwayoyin cuta suna ba da ƙarancin ƙarfin zafi don haka rage buƙatun makamashi yayin sabuntawa.
Sauran fa'idar yin amfani da sieves na ƙwayoyin ƙwayoyin cuta shine yawancin yawa yawanci ya fi sauran sifofi, don haka buƙatun buƙatu iri ɗaya ƙarar sieve kwayoyin da ake buƙata ya ragu. Don haka yayin da ake cire bottlenecking, mutum na iya amfani da sieves na kwayoyin halitta, ƙara ƙara ƙara a cikin girma ɗaya, kuma a guje wa kowane gyare-gyaren jirgin ruwa.
Lokacin aikawa: Yuli-18-2023
