Siyakwamukela kuwebhusayithi yethu ukuze uthole ulwazi mayelana nomkhiqizo kanye nokubonisana.
Iwebhusayithi yethu:https://www.vet-china.com/
Indlela yokusebenza ngokomzimba namakhemikhali
Indlela yokusebenza ngokomzimba nangokwekhemikhali ibhekisela endleleni yokulungiselela izinto ezinezimbobo ngokuhlanganisa izindlela ezimbili zokusebenzisa ezingenhla. Ngokuvamile, ukusebenza kwamakhemikhali kwenziwa kuqala, bese kwenziwa ukusebenza ngokomzimba. Okokuqala cwilisa i-cellulose kusisombululo se-H3PO4 esingu-68% ~ 85% ku-85℃ amahora ama-2, bese usifaka ku-carbon esithandweni somlilo amahora ama-4, bese usivuselela nge-CO2. Indawo ethile yobuso be-carbon esebenzayo etholiwe yayiphezulu njengo-3700m2·g-1. Zama ukusebenzisa i-sisal fiber njengezinto zokusetshenziswa, bese usebenzisa i-activated carbon fiber (ACF) etholiwe ngokusebenza kwe-H3PO4 kanye, uyifudumeze ku-830℃ ngaphansi kokuvikelwa kwe-N2, bese usebenzisa umhwamuko wamanzi njengesiqalisi sokuqalisa ukusebenza kwesibili. Indawo ethile yobuso be-ACF etholiwe ngemuva kwemizuzu engama-60 yokusebenza yathuthukiswa kakhulu.
Ukucaciswa kokusebenza kwesakhiwo sembobo se-activatedikhabhoni
Izindlela zokuchaza ukusebenza kwekhabhoni esebenzayo ezisetshenziswa kakhulu kanye neziqondiso zokusetshenziswa ziboniswe kuThebula 2. Izici zesakhiwo sembobo yezinto ezibonakalayo zingahlolwa kusukela ezicini ezimbili: ukuhlaziywa kwedatha kanye nokuhlaziywa kwesithombe.
Inqubekela phambili yocwaningo lobuchwepheshe bokwenza ngcono isakhiwo se-pore se-activated carbon
Nakuba ikhabhoni esebenzayo inezimbobo ezicebile kanye nendawo enkulu ethile, isebenza kahle kakhulu emikhakheni eminingi. Kodwa-ke, ngenxa yokukhetha kwayo okubanzi kwezinto zokusetshenziswa kanye nezimo zokulungiselela eziyinkimbinkimbi, imikhiqizo eqediwe ngokuvamile inezinkinga zesakhiwo se-pore esixakile, indawo ehlukile ethile, ukusatshalaliswa kosayizi we-pore ophazamisekile, kanye nezakhiwo zamakhemikhali ezilinganiselwe. Ngakho-ke, kunezinkinga ezifana nomthamo omkhulu kanye nokuzivumelanisa nezimo okuncane enkambisweni yokufaka isicelo, okungenakuhlangabezana nezidingo zemakethe. Ngakho-ke, kubaluleke kakhulu ukwenza ngcono nokulawula isakhiwo nokuthuthukisa ukusebenza kwaso okuphelele. Izindlela ezivame ukusetshenziswa zokuthuthukisa nokulawula isakhiwo se-pore zifaka phakathi ukulawulwa kwamakhemikhali, ukuxubana kwe-polymer, kanye nokulawulwa kokusebenza kwe-catalytic.
Ubuchwepheshe bokulawula amakhemikhali
Ubuchwepheshe bokulawula amakhemikhali bubhekisela enkambisweni yokusebenza kwesibili (ukuguqulwa) kwezinto ezinezimbobo ezitholakala ngemva kokusebenza ngama-reagent amakhemikhali, ukuguguleka kwama-pores okuqala, ukwandisa ama-micropores, noma ukudala ama-micropores amasha ukuze kwandiswe indawo ethile yobuso kanye nesakhiwo se-pore sezinto. Ngokuvamile, umkhiqizo oqediwe wokusebenza okukodwa uvame ukucwiliswa esisombululo samakhemikhali izikhathi ezingu-0.5 ~ 4 ukulawula isakhiwo se-pore nokwandisa indawo ethile yobuso. Zonke izinhlobo zezixazululo ze-asidi ne-alkali zingasetshenziswa njenge-reagents ukuze kusebenze kwesibili.
Ubuchwepheshe bokuguqulwa kwe-acid surface oxidation
Ukuguqulwa kwe-acid surface oxidation kuyindlela evame ukusetshenziswa yokulawula. Ezingeni lokushisa elifanele, ama-acid oxidants angacebisa ama-pores ngaphakathi kwe-activated carbon, athuthukise usayizi we-pore yayo, futhi akhiphe ama-pores avaliwe. Njengamanje, ucwaningo lwasekhaya nolwangaphandle lugxile kakhulu ekuguqulweni kwama-inorganic acid. I-HN03 iyi-oxidant evame ukusetshenziswa, futhi izazi eziningi zisebenzisa i-HN03 ukuguqula i-activated carbon. UTong Li et al. [28] bathole ukuthi i-HN03 ingakhuphula okuqukethwe kwamaqembu asebenzayo aqukethe umoya-mpilo kanye ne-nitrogen ebusweni be-activated carbon futhi ithuthukise umphumela wokumuncwa kwe-mercury.
Ukushintsha ikhabhoni esebenzayo nge-HN03, ngemva kokuguqulwa, indawo ethile ebusweni bekhabhoni esebenzayo yehle kusuka ku-652m2·g-1 kuya ku-241m2·g-1, usayizi we-pore omaphakathi ukhuphuke kusuka ku-1.27nm kuya ku-1.641nm, kanye nomthamo wokumunca we-benzophenone kuphethiloli elingisiwe ukhuphuke ngo-33.7%. Ukushintsha ikhabhoni esebenzayo yokhuni enevolumu engu-10% kanye no-70% yokuhlushwa kwe-HN03, ngokulandelana. Imiphumela ikhombisa ukuthi indawo ethile ebusweni bekhabhoni esebenzayo eguquliwe nge-10% HN03 ikhuphuke kusuka ku-925.45m2·g-1 kuya ku-960.52m2·g-1; ngemva kokuguqulwa nge-70% HN03, indawo ethile ebusweni yehle yaya ku-935.89m2·g-1. Amazinga okususwa kwe-Cu2+ ngekhabhoni esebenzayo eguquliwe enezinga ezimbili ze-HN03 ayengaphezu kuka-70% no-90%, ngokulandelana.
Kwikhabhoni esebenzayo esetshenziswa ensimini yokumunca, umphumela wokumunca awuxhomekile kuphela esakhiweni sembobo kodwa futhi nasezimpahleni zamakhemikhali ebusweni be-adsorbent. Isakhiwo sembobo sinquma indawo ethile ebusweni kanye nomthamo wokumunca wekhabhoni esebenzayo, kuyilapho izakhiwo zamakhemikhali ebusweni zithinta ukusebenzisana phakathi kwekhabhoni esebenzayo kanye ne-adsorbate. Ekugcineni kwatholakala ukuthi ukuguqulwa kwe-asidi kwekhabhoni esebenzayo akukwazi nje ukulungisa isakhiwo sembobo ngaphakathi kwekhabhoni esebenzayo futhi kususe ama-pores avinjiwe, kodwa futhi kwandisa okuqukethwe kwamaqembu e-acid ebusweni bezinto futhi kuthuthukise i-polarity kanye ne-hydrophilicity yobuso. Amandla okumunca e-EDTA yikhabhoni esebenzayo eguqulwe yi-HCI akhuphuke ngo-49.5% uma kuqhathaniswa nalawo angaphambi kokuguqulwa, okwakungcono kunokuguqulwa kwe-HNO3.
Ikhabhoni esebenzayo eshintshiwe yezentengiselwano ene-HNO3 kanye ne-H2O2 ngokulandelana! Izindawo ezithile zobuso ngemva kokuguqulwa zazingu-91.3% kanye no-80.8% walezo zangaphambi kokuguqulwa, ngokulandelana. Amaqembu amasha asebenzayo aqukethe umoya-mpilo njenge-carboxyl, i-carbonyl kanye ne-phenol anezelwa ebusweni. Amandla okumunca i-nitrobenzene ngokuguqulwa kwe-HNO3 ayengcono kakhulu, okwakuphindwe izikhathi ezingu-3.3 kunangaphambi kokuguqulwa. Kutholakale ukuthi ukwanda kokuqukethwe kwamaqembu asebenzayo aqukethe umoya-mpilo kukhabhoni esebenzayo ngemva kokuguqulwa kwe-asidi kuholele ekwandeni kwenani lamaphuzu asebenzayo ebusweni, okwaba nomthelela oqondile ekuthuthukiseni amandla okumunca i-adsorbate eqondiwe.
Uma kuqhathaniswa nama-asidi angaphili, kunemibiko embalwa mayelana nokuguqulwa kwe-organic acid kwe-activated carbon. Qhathanisa imiphumela yokuguqulwa kwe-organic acid ezimpahleni zesakhiwo se-pore se-activated carbon kanye nokumuncwa kwe-methanol. Ngemva kokuguqulwa, indawo ethile yobuso kanye nenani eliphelele le-pore ye-activated carbon lehlile. Uma i-acidity iqina, kulapho kwehla khona kakhulu. Ngemva kokuguqulwa nge-oxalic acid, i-tartaric acid kanye ne-citric acid, indawo ethile yobuso be-activated carbon yehle kusuka ku-898.59m2·g-1 kuya ku-788.03m2·g-1, 685.16m2·g-1 kanye no-622.98m2·g-1 ngokulandelana. Kodwa-ke, i-microporosity ye-activated carbon yanda ngemva kokuguqulwa. I-microporosity ye-activated carbon eguquliwe nge-citric acid yanda kusuka ku-75.9% kuya ku-81.5%.
Ukuguqulwa kwe-oxalic acid kanye ne-tartaric acid kuyasiza ekumuncweni kwe-methanol, kuyilapho i-citric acid inomphumela wokuvimbela. Kodwa-ke, u-J.Paul Chen et al. [35] bathole ukuthi i-activated carbon eguquliwe nge-citric acid ingathuthukisa ukumuncwa kwama-ion ethusi. U-Lin Tang et al. [36] ushintshe i-activated carbon ethengiswayo ene-formic acid, i-oxalic acid kanye ne-aminosulfonic acid. Ngemva kokuguqulwa, indawo ethile yobuso kanye nomthamo we-pore kwancishiswa. Amaqembu asebenzayo aqukethe i-oxygen njenge-0-HC-0, C-0 kanye ne-S=0 akhiwa ebusweni bomkhiqizo oqediwe, kwavela iziteshi ezingalingani kanye namakristalu amhlophe. Amandla okulingana okumuncwa kwe-acetone kanye ne-isopropanol nawo anda kakhulu.
Ubuchwepheshe bokuguqulwa kwesisombululo se-alkaline
Ezinye izazi zisebenzise nesixazululo se-alkaline ukwenza ukusebenza kwesibili ku-activated carbon. Faka ikhabhoni eqaliswe ngamalahle eyenziwe ekhaya ngesisombululo se-Na0H samazinga ahlukene ukulawula isakhiwo se-pore. Imiphumela ibonise ukuthi ukuhlushwa okuphansi kwe-alkaline kwakuhambisana nokwanda kwe-pore nokwanda kwayo. Umphumela omuhle kakhulu watholakala lapho ukuhlushwa kwesisindo kungu-20%. Ikhabhoni eqaliswe yayinendawo ephezulu kakhulu (681m2·g-1) kanye nomthamo we-pore (0.5916cm3·g-1). Lapho ukuhlushwa kwesisindo se-Na0H kudlula u-20%, isakhiwo se-pore se-activated carbon siyabhujiswa futhi amapharamitha esakhiwo se-pore aqala ukwehla. Lokhu kungenxa yokuthi ukuhlushwa okuphezulu kwesisombululo se-Na0H kuzokonakalisa uhlaka lwekhabhoni futhi inani elikhulu le-pore lizowa.
Ukulungiselela ikhabhoni esebenzayo esebenza kahle kakhulu ngokuxuba i-polymer. Izinto ezandulelayo kwakuyi-furfural resin kanye ne-furfuryl alcohol, kanti i-ethylene glycol yayiyi-ejenti eyakha i-pore. Isakhiwo se-pore sasilawulwa ngokulungisa okuqukethwe kwama-polymer amathathu, kwathi kwatholakala into enezimbobo ezinobukhulu be-pore obuphakathi kuka-0.008 no-5 μm. Ezinye izazi ziye zafakazela ukuthi ifilimu ye-polyurethane-imide (PUI) ingafakwa i-carbon ukuze kutholakale ifilimu yekhabhoni, kanti isakhiwo se-pore singalawulwa ngokushintsha isakhiwo se-molecular se-polyurethane (PU) prepolymer [41]. Lapho i-PUI ishiswa ku-200°C, i-PU kanye ne-polyimide (PI) kuzokhiqizwa. Lapho izinga lokushisa lokwelashwa kokushisa lenyuka laya ku-400°C, i-PU pyrolysis ikhiqiza igesi, okuholela ekwakhekeni kwesakhiwo se-pore kwifilimu ye-PI. Ngemuva kokufaka i-carbonization, kutholakala ifilimu yekhabhoni. Ngaphezu kwalokho, indlela yokuhlanganisa i-polymer ingathuthukisa nezinye izakhiwo zomzimba nezemishini zezinto ngezinga elithile.
Ubuchwepheshe bokulawula ukusebenza kwe-Catalytic
Ubuchwepheshe bokulawula ukusebenza kwe-catalytic empeleni buyinhlanganisela yendlela yokusebenzisa amakhemikhali kanye nendlela yokusebenzisa igesi eshisa kakhulu. Ngokuvamile, izinto zamakhemikhali zengezwa ezintweni zokusetshenziswa njengezinto zokusebenzisa i-carbonization, futhi lezi zinto zokusebenzisa i-catalyst zisetshenziselwa ukusiza inqubo yokwenza i-carbonization noma yokwenza i-activation ukuthola izinto ze-carbon ezinezimbobo. Ngokuvamile, izinsimbi ngokuvamile zinemiphumela yokusebenzisa i-catalytic, kodwa imiphumela yokusebenzisa i-catalytic iyahlukahluka.
Eqinisweni, ngokuvamile akukho mingcele ecacile phakathi kokulawulwa kokusebenza kwamakhemikhali kanye nokulawulwa kokusebenza kwe-catalytic kwezinto ezinezimbobo. Lokhu kungenxa yokuthi zombili lezi zindlela zengeza ama-reagent ngesikhathi senqubo yokwenza i-carbonization kanye nokusebenza. Indima ethile yalezi zi-reagent inquma ukuthi indlela ingeyesigaba sokusebenza kwe-catalytic.
Isakhiwo sezinto ezimbozwe nge-carbon uqobo, izakhiwo zomzimba nezamakhemikhali ze-catalyst, izimo zokusabela kwe-catalytic kanye nendlela yokulayisha i-catalyst konke kungaba nethonya elihlukile emphumeleni wokulawula. Ukusebenzisa amalahle e-bituminous njengezinto zokusetshenziswa, i-Mn(N03)2 kanye ne-Cu(N03)2 njengezinto zokusetshenziswa kungalungisa izinto ezimbozwe nge-pore eziqukethe ama-metal oxides. Inani elifanele lama-metal oxides lingathuthukisa i-porosity kanye ne-pore volume, kodwa imiphumela ye-catalytic yezinsimbi ezahlukene ihlukile kancane. I-Cu(N03)2 ingakhuthaza ukuthuthukiswa kwama-pores ebangeni eli-1.5 ~ 2.0nm. Ngaphezu kwalokho, ama-metal oxides kanye nosawoti we-inorganic oqukethwe kumlotha wezinto zokusetshenziswa nazo zizodlala indima ye-catalytic enqubweni yokusebenza. U-Xie Qiang et al. [42] bakholelwa ukuthi ukusabela kwe-catalytic activation kwezinto ezifana ne-calcium ne-iron ezintweni ezingezona ezingokwemvelo kungakhuthaza ukuthuthukiswa kwama-pores. Uma okuqukethwe kwalezi zinto ezimbili kuphezulu kakhulu, isilinganiso sama-pores aphakathi namakhulu kumkhiqizo sanda kakhulu.
Isiphetho
Nakuba ikhabhoni esebenzayo, njengezinto eziluhlaza ezimboza kakhulu ezisetshenziswa kakhulu, idlale indima ebalulekile embonini nasempilweni, isenamandla amakhulu okuthuthukisa ukwanda kwezinto ezingavuthiwe, ukunciphisa izindleko, ukuthuthukisa ikhwalithi, ukuthuthukisa amandla, ukwandisa impilo kanye nokuthuthukisa amandla. Ukuthola izinto eziluhlaza ezisebenza ngekhabhoni ezisebenzayo ezisezingeni eliphezulu nezishibhile, ukuthuthukisa ubuchwepheshe bokukhiqiza ikhabhoni esebenzayo ehlanzekile futhi esebenza kahle, kanye nokwenza ngcono nokulawula isakhiwo sembobo sekhabhoni esebenzayo ngokwezinkambu ezahlukene zohlelo lokusebenza kuzoba yisiqondiso esibalulekile sokuthuthukisa ikhwalithi yemikhiqizo yekhabhoni esebenzayo kanye nokukhuthaza intuthuko yekhwalithi ephezulu yemboni yekhabhoni esebenzayo.
Isikhathi sokuthunyelwe: Agasti-27-2024