isithwali se-catalyst kanye ne-zeolite

Sisebenzisa amakhukhi ukuthuthukisa ulwazi lwakho. Ngokuqhubeka uphequlula le sayithi, uyavuma ukusebenzisa kwethu amakhukhi. Ulwazi olwengeziwe.
Lesi sihloko sigxile ezimpahleni ze-acidity ebusweni bama-catalysts e-oxide kanye nezisekelo (γ-Al2O3, CeO2, ZrO2, SiO2, TiO2, HZSM5 zeolite) kanye nokutholakala okuqhathanisayo kwezindawo zazo ngokulinganisa i-temperature-programmed ammonia desorption (ATPD). I-ATPD iyindlela ethembekile nelula lapho ubuso, ngemva kokugcwala i-ammonia ekushiseni okuphansi, bushintsha khona izinga lokushisa, okuholela ekuncishisweni kwama-molecule e-probe kanye nokusatshalaliswa kwezinga lokushisa.
Ngokuhlaziywa kwenani kanye/noma kwekhwalithi kwephethini yokumunca, ulwazi lungatholakala ngamandla okumunca/ukumunca kanye nenani le-ammonia elimunca phezu komhlaba (ukuthathwa kwe-ammonia). Njenge-molecule eyisisekelo, i-ammonia ingasetshenziswa njenge-probe ukuthola i-asidi yobuso. Le datha ingasiza ukuqonda ukuziphatha kwe-catalytic kwamasampula futhi isize ngisho nokulungisa ukwenziwa kwezinhlelo ezintsha. Esikhundleni sokusebenzisa i-TCD detector yendabuko, kwasetshenziswa i-quadrupole mass spectrometer (i-Hiden HPR-20 QIC) kulo msebenzi, ixhunywe kudivayisi yokuhlola nge-capillary efudumele.
Ukusetshenziswa kwe-QMS kusenza sikwazi ukuhlukanisa kalula izinhlobo ezahlukene ezikhishwe emanzini ngaphandle kokusebenzisa noma yiziphi izihlungi zamakhemikhali noma zomzimba kanye nezicupho ezingathinta kabi ukuhlaziywa. Ukubekwa kahle kwamandla okwenziwa kwe-ionization kwethuluzi kusiza ukuvimbela ukuqhekeka kwama-molecule amanzi kanye nokuphazamiseka okubangelwa yisignali ye-ammonia m/z. Ukunemba nokuthembeka kwedatha yokususwa kwe-ammonia ehlelwe izinga lokushisa kuhlaziywe kusetshenziswa izindlela zokuhlola kanye nokuhlolwa kokuhlola, kugqamisa imiphumela yemodi yokuqoqwa kwedatha, igesi yokuthwala, usayizi wezinhlayiya, kanye ne-geometry ye-reactor, okubonisa ukuguquguquka kwendlela esetshenzisiwe.
Zonke izinto ezifundwe zinezindlela eziyinkimbinkimbi ze-ATPD ezihlanganisa ububanzi obungu-423-873K, ngaphandle kwe-cerium, ekhombisa iziqongo ezincane zokukhipha amanzi ezixazululiwe ezibonisa i-asidi ephansi efanayo. Idatha yobuningi ikhombisa umehluko ekuthathweni kwe-ammonia phakathi kwezinye izinto kanye ne-silica ngaphezu komyalelo wobukhulu. Njengoba ukusatshalaliswa kwe-ATPD kwe-cerium kulandela ijika le-Gaussian kungakhathaliseki ukumbozwa kobuso kanye nesivinini sokushisa, ukuziphatha kwezinto ezifundwayo kuchazwa njengokuhleleka kwemisebenzi emine ye-Gaussian ehlotshaniswa nenhlanganisela yamaqembu esayithi aphakathi nendawo, abuthakathaka, aqinile, nanamandla kakhulu. Lapho yonke idatha isiqoqiwe, ukuhlaziywa kwemodeli ye-ATPD kwasetshenziswa ukusiza ukuthola ulwazi ngamandla okumunca e-molecule ye-probe njengomsebenzi wokushisa ngakunye kokukhipha amanzi. Ukusatshalaliswa kwamandla okuqongelelekayo ngendawo kubonisa amanani alandelayo e-asidi asekelwe kumanani ajwayelekile wamandla (ku-kJ/mol) (isb. ukumbozwa kobuso θ = 0.5).
Njengokusabela kwe-probe, i-propene yacwiliswa i-isopropanol ukuze kutholakale ulwazi olwengeziwe mayelana nokusebenza kwezinto ezifundwayo. Imiphumela etholakele yayihambisana nokulinganiswa kwangaphambilini kwe-ATPD maqondana namandla kanye nobuningi bezindawo ze-asidi engaphezulu, futhi yenze kwaba nokwenzeka ukuhlukanisa phakathi kwezindawo ze-asidi ze-Brønsted kanye ne-Lewis.
Umfanekiso 1. (Kwesobunxele) Ukususwa kwephrofayili ye-ATPD kusetshenziswa umsebenzi we-Gaussian (umugqa ophuzi onamachashazi umele iphrofayili ekhiqiziwe, amachashazi amnyama ayidatha yokuhlola) (kwesokudla) Umsebenzi wokusabalalisa amandla okukhishwa kwe-ammonia ezindaweni ezahlukahlukene.
URoberto Di Cio Faculty of Engineering, University of Messina, Contrada Dee Dee, Sant'Agata, I-98166 Messina, Italy
UFrancesco Arena, uRoberto Di Cio, uGiuseppe Trunfio (2015) “Ukuhlolwa Kokuhlola Kwendlela Yokuncibilikisa Ukushisa Okuhlelwe yi-Ammonia Yokuphenya Izakhiwo Ze-Acid Zezindawo Ezinezinhlayiya Ezingafani” I-Applied Catalysis A: Isibuyekezo 503, 227-236
Fihla ukuhlaziya. (9 kuNhlolanja 2022). Ukuhlolwa kokuhlola kwendlela yokukhipha i-ammonia okuhlelwe ngokushisa ukuze kufundwe izakhiwo ze-asidi zezindawo ezingafani zama-catalyst. AZ. Kuthathwe ngoSepthemba 7, 2023 ku-https://www.azom.com/article.aspx?ArticleID=14016.
Fihla ukuhlaziya. “Ukuhlolwa Kokuhlola Kwendlela Yokuncibilikisa I-Ammonia Ehlelwe Ukushisa Yokufunda Izakhiwo Ze-Acid Zezindawo Ezine-Heterogeneous Catalyst”. AZ. Septhemba 7, 2023 .
Fihla ukuhlaziya. “Ukuhlolwa Kokuhlola Kwendlela Yokuncibilikisa I-Ammonia Ehlelwe Ukushisa Yokufunda Izakhiwo Ze-Acid Zezindawo Ezingenazo Izinto Eziningi”. AZ. https://www.azom.com/article.aspx?ArticleID=14016. (Kufinyelelwe: Septhemba 7, 2023).
Fihla ukuhlaziya. 2022. Ukuhlolwa kokuhlola kwendlela yokukhipha i-ammonia ehlelwe ngokushisa ukuze kufundwe izakhiwo ze-asidi zezindawo ze-catalyst ezingafani. I-AZoM, ifinyelelwe ngo-7 Septhemba 2023, https://www.azom.com/article.aspx?ArticleID=14016.