Indlela Inqubo Yokusabela KaHaber Bosch Esebenza Ngayo
Inqubo ye-Haber-Bosch ingenye yezinto ezibaluleke kakhulu ezitholakale emlandweni wekhemistri yezimboni ngoba ivumela abantu ukuthi bakhiqize i-ammonia (NH₃) ngezinga elikhulu kusuka kumagesi amabili atholakala ngokwemvelo: i-nitrogen (N₂) emoyeni kanye ne-hydrogen (H₂), evame ukutholakala kusuka kugesi yemvelo noma eminye imithombo. I-Ammonia ibe isiba yizinto ezisetshenziswa kakhulu zomanyolo we-nitrogen njenge-urea kanye ne-ammonium nitrate, ezidlala indima enkulu ekwandiseni umkhiqizo wezolimo emhlabeni jikelele. Ngaphandle kwale nqubo, ukutholakala kokudla emhlabeni wonke cishe bekuyoba kuncane kakhulu.
Ingemuva: kungani kunzima "ukuyibamba" i-nitrogen?
Nakuba umoya uqukethe cishe i-nitrogen engu-78%, igesi i-N₂ izinzile kakhulu ngoba ama-athomu ayo amabili e-nitrogen aboshwe yisibopho esiqinile esiphindwe kathathu (N≡N). Lesi sibopho yisona esenza i-nitrogen “ingafuni” ukusabela. Izitshalo empeleni zidinga i-nitrogen ukuze zenze amaprotheni nama-nucleic acid, kodwa azikwazi ukusebenzisa i-N₂ ngqo emoyeni. Ngokwemvelo, i-nitrogen iqiniswa amabhaktheriya athile noma ngombani, kodwa izinga lalezi zinqubo zemvelo alanele ukuhlangabezana nezidingo zezolimo zanamuhla. Yilapho i-Haber-Bosch ingena khona: ukuhlinzeka ngendlela “yokuphoqa” i-nitrogen ukuthi isabele ngezimo eziklanywe kahle kanye nama-catalyst.
Impendulo eyinhloko: kusukela ku-nitrogen ne-hydrogen kuya ku-ammonia
I-equation yokusabela okuyinhloko yenqubo ye-Haber-Bosch yile:
N₂(g) + 3H₂(g) ⇌ 2NH₃(g) + ukushisa
Lokhu kusabela kuyaguqulwa (kungaqhubeka kuzo zombili izinkomba) futhi kube yi-exothermic (kukhiqiza ukushisa). Lokhu kusho ukuthi ukwakheka kwe-ammonia kuyathandwa emazingeni okushisa aphansi ngokwesimiso sokulingana, kodwa emazingeni okushisa aphansi kakhulu ukusabela kuqhubeka kancane kakhulu. Ngakho-ke, izinqubo zezimboni kumele zithole ukuvumelana phakathi kwesilinganiso sokusabela kanye nesivuno sokulingana.
Izigaba eziyinhloko enkambisweni yeHaber-Bosch
Ngokuvamile, inqubo yezimboni ye-Haber-Bosch ihlanganisa izigaba eziningana: ukuhlinzekwa kwezinto zokusetshenziswa (i-H₂ ne-N₂), ukuhlanzwa, ukucindezela, ukusabela kokwenziwa nge-catalyst, ukuhlukaniswa kwe-ammonia, kanye nokuvuselelwa kwegesi engaphenduliwe.
1. Imithombo kanye nokukhiqizwa kwe-hydrogen (H₂)
I-hydrogen yenqubo ye-Haber-Bosch ivame ukuvela ekuguqulweni kwegesi yemvelo (i-methane, i-CH₄). Izinyathelo zifaka:
– Ukuguqulwa kwe-methane ngomusi (SMR): i-methane isabela ngomhwamuko wamanzi emazingeni okushisa aphezulu ukuze ikhiqize ingxube yegesi (ama-synga) equkethe i-H₂, i-CO₂, kanye ne-CO₂.
– Ukusabela kokushintsha kwegesi yamanzi: I-CO2 iphinda isabela ngomhwamuko wamanzi ukuze ikhiqize i-CO2 bese ifaka i-H₂.
Ekugcineni, i-CO₂ iyahlukaniswa bese i-hydrogen ihlanzwa. Kwezinye izitshalo, i-hydrogen ingatholakala futhi ku-electrolysis yamanzi, ikakhulukazi lapho kutholakala khona ugesi ovuselelekayo, yize lokhu kuvame ukubiza kakhulu ngokwezomnotho kunegesi yemvelo.
2. Ukuthatha i-nitrogen (N₂) emoyeni
I-nitrogen ngokuvamile ikhishwa ngokuhlukaniswa komoya kusetshenziswa amayunithi e-cryogenic (ukupholisa kuze kube amazinga okushisa aphansi kakhulu) noma obunye ubuchwepheshe obufana nokudonswa kwe-pressure swing (PSA). Umgomo ukuthola i-nitrogen ehlanzekile kakhulu, njengoba ezinye izinto ezingcolile zingaba ubuthi ku-catalyst futhi ziphazamise ukusabela.
3. Ukuhlanzwa kwegesi: ukususa “ubuthi” be-catalyst
Ama-catalyst asetshenziswa eHaber-Bosch (ngokuvamile asekelwe ensimbini) azwela kakhulu ezintweni ezifana ne-sulfur (S), i-carbon monoxide (CO), kanye nokunye ukungcola okuningana. Ngakho-ke, igesi yokudla kumele ihlanzwe:
– Amakhemikhali esibabule asuswa kusetshenziswa ama-adsorbents akhethekile.
– I-CO2 kanye ne-CO2 ziphathwa ngokusebenzisa ukusabela kwamakhemikhali (ukushintsha, i-methanation) noma ukuhlukaniswa ngokomzimba/kwamakhemikhali.
– Umswakama (H₂O) nawo uyancishiswa ukuze ungaphazamisi inqubo.
Lokhu kuhlanzwa kubaluleke kakhulu ngoba ukusebenza kahle kwezitshalo kanye nokuphila kwe-catalyst kuncike kakhulu ekuhlanzekeni kwegesi.
4. Ukucindezela: ukucindezela okwandisa ukushintsha ukulingana
Ukusabela kukhiqiza ama-moles ambalwa egesi (kusukela kuma-moles ama-4 egesi kuya kuma-moles ama-2 egesi). Ngokomgomo kaLe Chatelier, ukucindezela okuphezulu kuzoshintsha ukulingana kuye kumkhiqizo (i-NH₃). Ngakho-ke, ingxube ye-N₂ ne-H₂ icindezelwa ibe yizingcindezi eziphezulu, ngokuvamile emakhulwini emimoya emikhubeni yesimanje yezimboni (inani eliqondile lingahluka kuye ngomklamo wesitshalo).
Kodwa-ke, ukucindezela okuphezulu kusho izidingo ezinkulu zamandla ze-compressor, ngakho-ke isitshalo kumele sithuthukise phakathi kwentengo ye-ammonia kanye nezindleko zamandla.
5. I-synthesis reactor: indima ye-catalyst kanye nokushisa okusebenzayo
Ku-reactor, ingxube ye-N₂ kanye ne-H₂ idluliselwa phezu kwe-catalyst. I-catalyst yakudala yenqubo ye-Haber-Bosch yi-iron (Fe) enama-promoter afana ne-potassium oxide (K₂O), i-aluminium oxide (Al₂O₃), kanye ne-calcium oxide (CaO). Ama-promoter asiza ukwandisa umsebenzi kanye nokuqina kwe-catalyst.
Izinga lokushisa lokusabela ngokuvamile libekwa phezulu ngokwanele ukuqinisekisa izinga lokusabela elanele. Kodwa-ke, ngenxa yokuthi ukusabela kokwakheka kwe-ammonia kuyinto exothermic, amazinga okushisa aphezulu kakhulu empeleni anciphisa isivuno sokulingana. Ngakho-ke, izinga lokushisa libekwa ngaphakathi kobubanzi bokuvumelana obuvumela ukusabela ukuthi kuqhubeke ngokushesha ngenkathi kusakhiqiza isivuno esihle.
Ezingeni lama-molecule, ama-catalyst asebenza ngokuthi:
– Ukuphula izibopho ze-N≡N ebusweni be-catalyst (lesi yisinyathelo esinzima kakhulu).
– Imunca i-H₂ bese iyihlukanisa ibe ama-athomu e-H.
– Kusiza ukwakheka kancane kancane kwama-N–H bond kuze kube yilapho kwakheka i-NH₃.
– Ukukhipha i-NH₃ ebusweni be-catalyst ukuze izindawo ezisebenzayo ziphinde zisetshenziswe.
6. Ukupholisa kanye nokujiya: ukuhlukanisa i-ammonia negesi
Ngemva kokuphuma ku-reactor, ingxube yegesi iqukethe i-NH₃ kanye ne-N₂ engaphenduliwe kanye ne-H₂. Le ngxube iyapholiswa. I-Ammonia incibilikiswa kalula ngaphansi kwezimo ezithile, okuvumela ukuthi ihlukaniswe ngokujiya ibe yi-ammonia ewuketshezi.
Lokhu kuhlukaniswa okusekelwe ekuvundeni kuwusizo kakhulu ngoba:
- Thola umkhiqizo oyinhloko ngendlela efanele
– Kukhuthaza ukusabela ukuthi kuqhubeke (imikhiqizo iyathathwa, ukulingana kusunduzelwa emikhiqizweni)
7. Ukuvuselelwa kwegesi: kwandisa ukusebenza kahle okuphelele
Akuzona zonke i-N₂ ne-H₂ eziguqulwa zibe yi-NH₃ ngokudlula okukodwa ku-reactor. Ngakho-ke, igesi esele ivame ukuphinda isetshenziswe ibuyele ku-reactor ngemva kokuhlukaniswa ne-ammonia. Ukuphinda kusetshenziswe kwandisa kakhulu izinga lokuguqulwa kwenqubo futhi kwenza ukusetshenziswa kwezinto zokusetshenziswa kusebenze kahle kakhulu.
Ngesikhathi esifanayo, ingxenye encane yegesi ingase “ihlanzwe” ukuze kuvinjelwe ukwakheka kwezinto ezingasebenzi njenge-argon ezithwalwa emoyeni.
Izici ezithonya imiphumela yenqubo
Kunezici ezintathu ezibalulekile ezixoxwa ngazo njalo ku-Haber-Bosch:
1. Ingcindezi: lapho ingcindezi iphakeme, kulapho ukuthambekela kokukhiqiza i-NH₃ kukhulu khona.
2. Izinga lokushisa: amazinga okushisa aphansi athanda ukulingana, kodwa amazinga okushisa aphezulu asheshisa izinga lokusabela.
3. I-Catalyst: isheshisa ukufezwa kokulingana ngaphandle kokushintsha isikhundla sokulingana ngokwaso.
Izimboni zikhetha izimo zokusebenza ezifanele kakhulu ezicabangela ukonga, ukuphepha, ukusebenza kahle kwamandla, kanye nokuqina kwemishini.
Imithelela yanamuhla kanye nezinselele
Inqubo ye-Haber-Bosch ibe usizo kakhulu kwezolimo, kodwa futhi ibangela izinselele zemvelo. Ukukhiqiza i-hydrogen kusuka kugesi yemvelo kukhiqiza ukukhishwa kwe-CO₂. Ngakho-ke, ucwaningo oluningi lwanamuhla luqondiswe ku:
– I-hydrogen “eluhlaza” evela ku-electrolysis yamanzi asekelwe emandleni avuselelekayo
– Ukubanjwa nokugcinwa kwekhabhoni (CCS) ezitshalweni ze-ammonia
– Ukuthuthukiswa kwama-catalyst amasha ukuze kwenzeke ukusabela ekucindezelekeni okuphansi noma emazingeni okushisa aphansi
Le mizamo ihlose ukugcina izinzuzo ezibalulekile ze-ammonia—ikakhulukazi njengomanyolo—ngenkathi yehlisa umthelela wayo wekhabhoni.
Isiphetho
Inqubo ye-Haber-Bosch iwuchungechunge lwezinyathelo zezimboni ezenzelwe ukunqoba ukuzinza kwe-nitrogen emoyeni nokukhiqiza i-ammonia ngobuningi. Empeleni iyimpendulo eqhutshwa yi-catalyst ye-N₂ ne-H₂, eyenziwe ngcono ngokucindezela okuphezulu, amazinga okushisa aphansi, ukuhlanzwa kwegesi, kanye nohlelo lokuhlukanisa nokuvuselela kabusha. Umphumela uba ukukhiqizwa kwe-ammonia, umgogodla womanyolo wesimanje kanye nesisekelo esibalulekile sokuvikeleka kokudla emhlabeni jikelele. Inselele ebalulekile yesikhathi esizayo sale nqubo ukwenza ibe nobungane kakhulu nemvelo ngokusebenzisa imithombo ye-hydrogen ekhipha ukungcola okuncane kanye nokusebenza kahle kwamandla okuthuthukisiwe.
