Sisebenzisa amakhukhi ukuthuthukisa ulwazi lwakho. Ngokuqhubeka nokuphequlula leli sayithi, uyavumelana nokusebenzisa kwethu amakhukhi. Ulwazi olwengeziwe.
Lesi sihloko sigxile ezicini ze-asidi engaphezulu yezisusa ze-oxide nezisekelo (γ-Al2O3, CeO2, ZrO2, SiO2, TiO2, HZSM5 zeolite) kanye nokutholwa okuqhathaniswayo kwezindawo zazo ngokulinganisa i-ammonia desorption (ATPD) ehlelwe ngokwezinga lokushisa. I-ATPD iyindlela enokwethenjelwa nelula lapho indawo engaphezulu, ngemva kokugcwala i-ammonia ezingeni lokushisa eliphansi, ishintshe izinga lokushisa, okuholela ekuncipheni kwama-molecule e-probe kanye nokusatshalaliswa kwezinga lokushisa.
Ngokuhlaziywa kobuningi kanye/noma kwekhwalithi kwephethini yokuncibilika, ulwazi lungatholwa ngamandla e-desorption/adsorption kanye nenani le-ammonia elikhangiswa phezulu (ukuthathwa kwe-ammonia). Njenge-molecule eyisisekelo, i-ammonia ingasetshenziswa njenge-probe ukuze kutholakale i-asidi yendawo. Le datha ingasiza ukuqonda ukuziphatha kwe-catalytic kwamasampuli futhi isize nokushuna kahle ukuhlanganiswa kwamasistimu amasha. Esikhundleni sokusebenzisa umtshina we-TCD ovamile, i-quadrupole mass spectrometer (Hiden HPR-20 QIC) isetshenziswe emsebenzini, exhunywe kudivayisi yokuhlola nge-capillary eshisayo.
Ukusetshenziswa kwe-QMS kusivumela ukuthi sikwazi ukuhlukanisa kalula phakathi kwezinhlobo ezahlukene zezinhlobo ezincibilikisiwe ngaphandle kokusebenzisa izihlungi zamakhemikhali noma ezibonakalayo nezicupho ezingase zibe nomthelela omubi ekuhlaziyeni. Ukusetha okufanelekile kwamandla e-ionization wensimbi kusiza ukuvimbela ukuhlukana kwama-molecule wamanzi kanye nomphumela wokuphazamiseka kwesiginali ye-ammonia m/z. Ukunemba nokuthembeka kwedatha ye-ammonia desorption ehlelwe izinga lokushisa kwahlaziywa kusetshenziswa imibandela yethiyori kanye nokuhlolwa kokuhlola, okugqamisa imiphumela yemodi yokuqoqwa kwedatha, igesi yenkampani yenethiwekhi, usayizi wezinhlayiyana, kanye nejiyomethri ye-reactor, okubonisa ukuguquguquka kwendlela esetshenzisiwe.
Zonke izinto ezifundwayo zinezindlela eziyinkimbinkimbi ze-ATPD ezihlanganisa uhla lwe-423-873K, ngaphandle kwe-cerium, ebonisa iziqongo ezixazululiwe zokuncibilika ezibonisa i-asidi ephansi efanayo. Idatha yobuningi ibonisa umehluko ekuthathweni kwe-ammonia phakathi kwezinye izinto zokwakha kanye ne-silica ngaphezu kwe-oda lobukhulu. Njengoba ukusatshalaliswa kwe-ATPD kwe-cerium kulandela ijika le-Gaussian kungakhathaliseki ukumbozwa kwendawo nezinga lokushisa, ukuziphatha kwento efundwayo kuchazwa njengokulandelana kwemisebenzi emine ye-Gaussian ehlotshaniswa nenhlanganisela yamaqembu esayithi amaphakathi, abuthaka, aqinile, futhi aqine kakhulu. . Lapho yonke idatha isiqoqiwe, ukuhlaziywa kokumodela kwe-ATPD kwasetshenziswa ukusiza ukuthola ulwazi mayelana namandla e-adsorption we-molecule ye-probe njengomsebenzi wezinga lokushisa ngalinye le-desorption. Ukusatshalaliswa kwamandla anqwabelene ngendawo kubonisa amanani e-asidi alandelayo asekelwe kumanani wamandla amaphakathi (ku-kJ/mol) (isb. ukumbozwa kwendawo θ = 0.5).
Njengokusabela kwe-probe, i-propene yafakwa ngaphansi kokuphelelwa amanzi emzimbeni kwe-isopropanol ukuze ithole ulwazi olwengeziwe mayelana nokusebenza kwezinto ezifundwayo. Imiphumela etholiwe yayihambisana nezilinganiso zangaphambilini ze-ATPD ngokwamandla nobuningi bezindawo ze-asidi engaphezulu, futhi yenza kwaba nokwenzeka ukuhlukanisa phakathi kwezindawo ze-Brønsted ne-Lewis acid.
Umfanekiso 1. (Kwesobunxele) Ukuguqulwa kwephrofayili ye-ATPD kusetshenziswa umsebenzi we-Gaussian (umugqa onamachashazi aphuzi umele iphrofayela ekhiqiziwe, amachashazi amnyama ayidatha yokuhlola) (kwesokudla) umsebenzi wokusabalalisa amandla we-ammonia desorption ezindaweni ezihlukahlukene.
URoberto Di Cio Faculty of Engineering, University of Messina, Contrada Dee Dee, Sant'Agata, I-98166 Messina, Italy
U-Francesco Arena, u-Roberto Di Cio, u-Giuseppe Trunfio (2015) "Ukuhlolwa Kokuhlola Kwendlela Yokulahla I-ammonia Temperature-Programmed Desorption Yokuhlola Izakhiwo Ze-Acid Yezindawo Ze-Heterogeneous Catalyst" Kusetshenziswe I-Catalysis A: Buyekeza 503, 227-236
Fihla izibalo. (Februwari 9, 2022). Ukuhlolwa kokuhlola kwendlela yokushisa okuhleliwe kwe-ammonia ukuze kufundwe izici ze-asidi zezindawo ezihlukene zama-catalysts. AZ. Ibuyiselwe ngoSepthemba 7, 2023 kusukela ku-https://www.azom.com/article.aspx?ArticleID=14016.
Fihla izibalo. "Ukuhlolwa Kokuhlola Kwendlela Yokushisa I-ammonia Ehlelwe Ngamazinga Okushisa Yokufunda Izakhiwo Ze-Acid Yezindawo Ezihlukahlukene Ze-Catalyst". AZ. Septhemba 7, 2023
Fihla izibalo. "Ukuhlolwa Kokuhlola Kwendlela Yokushisa Ye-ammonia Ehlelwe Ngamazinga Okushisa Yokufunda Izakhiwo Ze-Acid Yezindawo Ezihlukahlukene Ze-Catalyst". AZ. https://www.azom.com/article.aspx?ArticleID=14016. (Kufinyelelwe: Septhemba 7, 2023).
Fihla izibalo. 2022. Ukuhlolwa kokuhlolwa kwendlela yokushisa i-ammonia desorption ehlelwe izinga lokushisa ukuze kufundwe izici ezine-asidi zezindawo ze-catalyst ezihlukile. I-AZoM, ifinyelelwe ngomhla ka-7 Septhemba 2023, https://www.azom.com/article.aspx?ArticleID=14016.
Isikhathi sokuthumela: Sep-07-2023
