Wamkelekile kwiwebhusayithi yethu ukuze ufumane ulwazi ngemveliso kunye nokubonisana.
Iwebhusayithi yethu:https://www.vet-china.com/
Indlela yokusebenza ngokwasemzimbeni nangokweekhemikhali
Indlela yokusebenza ngokwasemzimbeni nangokweekhemikhali ibhekisa kwindlela yokulungiselela izinto ezinemingxuma ngokudibanisa ezi ndlela zimbini zokuqalisa ezingentla. Ngokubanzi, ukusebenza kweekhemikhali kwenziwa kuqala, emva koko ukusebenza ngokwasemzimbeni kwenziwa. Okokuqala faka i-cellulose kwisisombululo se-68% ~ 85% H3PO4 kwi-85℃ iiyure ezi-2, uze uyifake kwi-muffle furnace iiyure ezi-4, uze uyisebenze nge-CO2. Indawo ethile yomphezulu wekhabhoni esebenzayo efunyenweyo yayiphezulu njenge-3700m2·g-1. Zama ukusebenzisa i-sisal fiber njengezinto eziluhlaza, uze usebenze i-activated carbon fiber (ACF) efunyenwe yi-H3PO4 activation kanye, uyifudumeze ukuya kwi-830℃ phantsi kokhuseleko lwe-N2, uze usebenzise umphunga wamanzi njengesiqalisi sokuqalisa okwesibini. Indawo ethile yomphezulu we-ACF efunyenwe emva kwemizuzu engama-60 yokusebenza iphuculwe kakhulu.
Ukuchazwa kokusebenza kwesakhiwo se-pore se-activatedikhabhoni
Iindlela zokuchaza ukusebenza kwekhabhoni esebenzayo ezisetyenziswa rhoqo kunye nemiyalelo yokusetyenziswa ziboniswe kwiTheyibhile 2. Iimpawu zesakhiwo seembobo zezinto zinokuvavanywa kwiinkalo ezimbini: uhlalutyo lwedatha kunye nohlalutyo lomfanekiso.
Inkqubela phambili yophando lwetekhnoloji yokwenza ngcono ulwakhiwo lwe-pore structure ye-activated carbon
Nangona ikhabhoni esebenzayo ineembobo ezityebileyo kunye nendawo enkulu ethile yomphezulu, isebenza kakuhle kakhulu kwiinkalo ezininzi. Nangona kunjalo, ngenxa yokukhetha kwayo izinto eziluhlaza kunye neemeko zokulungiselela ezinzima, iimveliso ezigqityiweyo zihlala zineengxaki zesakhiwo seembobo ezingalawulekiyo, indawo eyahlukileyo yomphezulu, ukusasazwa kobukhulu beembobo ezingalungelelananga, kunye neempawu zekhemikhali zomphezulu ezilinganiselweyo. Ke ngoko, kukho iingxaki ezifana nomthamo omkhulu kunye nokuguquguquka okuncinci kwinkqubo yokufaka isicelo, okungenakwanelisa iimfuno zemarike. Ke ngoko, kubaluleke kakhulu ukwenza ngcono nokulawula isakhiwo kunye nokuphucula ukusebenza kwaso okubanzi. Iindlela ezisetyenziswa rhoqo zokuphucula nokulawula isakhiwo seembobo ziquka ukulawulwa kweekhemikhali, ukuxuba ipolymer, kunye nokulawulwa kokusebenza kwe-catalytic.
Itekhnoloji yokulawula iikhemikhali
Itekhnoloji yokulawula iikhemikhali ibhekisa kwinkqubo yokuvuselela okwesibini (ukuguqulwa) kwezinto ezinemingxuma ezifunyenwe emva kokuvuselela ngee-reagents zeekhemikhali, ukutshabalalisa ii-pores zokuqala, ukwandisa ii-micropores, okanye ukudala ngakumbi ii-micropores ezintsha ukwandisa indawo ethile yomphezulu kunye nolwakhiwo lwee-pore zezinto. Ngokubanzi, imveliso egqityiweyo yokuvuselela okukodwa idla ngokuntywiliselwa kwisisombululo seekhemikhali esiphindwe kayi-0.5 ~ 4 ukulawula isakhiwo se-pore kunye nokwandisa indawo ethile yomphezulu. Zonke iintlobo zezisombululo ze-asidi kunye ne-alkali zingasetyenziswa njengee-reagents zokuvuselela okwesibini.
Itekhnoloji yokuguqula i-asidi kumphezulu we-oxidation
Ukuguqulwa kwe-asidi kumphezulu we-oxidation yindlela esetyenziswa kakhulu yokulawula. Kwiqondo lobushushu elifanelekileyo, ii-acid oxidants zinokutyebisa ii-pores ezingaphakathi kwe-activated carbon, ziphucule ubungakanani bee-pore zayo, kwaye zikhuphe ii-pore ezivaliweyo. Okwangoku, uphando lwasekhaya nolwangaphandle lugxile kakhulu ekuguqulweni kwee-inorganic acids. I-HN03 yi-oxidant esetyenziswa kakhulu, kwaye uninzi lwabaphengululi basebenzisa i-HN03 ukuguqula i-activated carbon. UTong Li et al. [28] bafumanise ukuba i-HN03 inokunyusa umxholo wamaqela asebenzayo ane-oxygen kunye ne-nitrogen kumphezulu we-activated carbon kwaye iphucule isiphumo sokutsalwa kwe-mercury.
Ukutshintsha ikhabhoni esebenzayo nge-HN03, emva kokutshintsha, indawo ethile yomphezulu wekhabhoni esebenzayo yehle ukusuka kwi-652m2·g-1 ukuya kwi-241m2·g-1, ubungakanani obuphakathi bembobo bunyuke ukusuka kwi-1.27nm ukuya kwi-1.641nm, kwaye amandla okufunxa i-benzophenone kwipetroli elinganisiweyo anyuke nge-33.7%. Ukutshintsha ikhabhoni esebenzayo yomthi ene-10% kunye ne-70% yomthamo we-HN03, ngokwahlukeneyo. Iziphumo zibonisa ukuba indawo ethile yomphezulu wekhabhoni esebenzayo eguqulwe nge-10% HN03 inyuke ukusuka kwi-925.45m2·g-1 ukuya kwi-960.52m2·g-1; emva kokutshintsha nge-70% HN03, indawo ethile yomphezulu yehle ukuya kwi-935.89m2·g-1. Amanqanaba okususa i-Cu2+ yikhabhoni esebenzayo eguqulweyo ene-HN03 ezimbini ayengaphezulu kwe-70% kunye ne-90%, ngokwahlukeneyo.
Kwikhabhoni esebenzayo esetyenziswa kwintsimi yokufunxa, isiphumo sokufunxa asixhomekekanga kuphela kwisakhiwo sembobo kodwa nakwiimpawu zeekhemikhali zomphezulu we-adsorbent. Isakhiwo sembobo simisela indawo ethile yomphezulu kunye nomthamo wokufunxa wekhabhoni esebenzayo, ngelixa iimpawu zeekhemikhali zomphezulu zichaphazela ukusebenzisana phakathi kwekhabhoni esebenzayo kunye ne-adsorbate. Ekugqibeleni kwafunyaniswa ukuba ukuguqulwa kwe-asidi yekhabhoni esebenzayo akunakulungisa kuphela isakhiwo sembobo ngaphakathi kwekhabhoni esebenzayo kunye nokucoca iimbobo ezivaliweyo, kodwa kwandisa umxholo wamaqela e-acid kumphezulu wezinto kwaye kunyuse i-polarity kunye ne-hydrophilicity yomphezulu. Umthamo wokufunxa we-EDTA yikhabhoni esebenzayo eguqulwe yi-HCI unyuke nge-49.5% xa kuthelekiswa nalowo wangaphambi kokuguqulwa, owawungcono kunowokuguqulwa kwe-HNO3.
Ikhabhoni esebenzayo etshintshiweyo yorhwebo ene-HNO3 kunye ne-H2O2 ngokwahlukeneyo! Iindawo ezithile zomphezulu emva kokuguqulwa zaziyi-91.3% kunye ne-80.8% yezo zangaphambi kokuguqulwa, ngokwahlukeneyo. Amaqela amatsha asebenzayo aneoksijini afana ne-carboxyl, i-carbonyl kunye ne-phenol ongezwe kumphezulu. Amandla okufunxa i-nitrobenzene ngokuguqulwa kwe-HNO3 yayiyeyona ilungileyo, eyayiphindwe kathathu kuneyangaphambi kokuguqulwa. Kufunyaniswe ukuba ukwanda komxholo wamaqela asebenzayo aneoksijini kwikhabhoni esebenzayo emva kokuguqulwa kwe-asidi kukhokelele ekwandeni kwenani lamanqaku asebenzayo kumphezulu, nto leyo eyaba nefuthe ngqo ekuphuculeni amandla okufunxa i-adsorbate ekujoliswe kuyo.
Xa kuthelekiswa nee-asidi ezingaphiliyo, zimbalwa iingxelo malunga nokuguqulwa kwe-organic acid ye-carbon esebenzayo. Thelekisa imiphumo yokuguqulwa kwe-organic acid kwiimpawu zesakhiwo se-pore se-carbon esebenzayo kunye nokutsalwa kwe-methanol. Emva kokuguqulwa, indawo ethile yomphezulu kunye nomthamo we-pore iyonke ye-carbon esebenzayo yehla. Okukhona i-acidity iqina, kokukhona ihla kakhulu. Emva kokuguqulwa nge-oxalic acid, i-tartaric acid kunye ne-citric acid, indawo ethile yomphezulu we-carbon esebenzayo yehla ukusuka kwi-898.59m2·g-1 ukuya kwi-788.03m2·g-1, 685.16m2·g-1 kunye ne-622.98m2·g-1 ngokwahlukeneyo. Nangona kunjalo, i-microporosity ye-carbon esebenzayo yanda emva kokuguqulwa. I-microporosity ye-carbon esebenzayo eguqulwe nge-citric acid yanda ukusuka kwi-75.9% ukuya kwi-81.5%.
Ukuguqulwa kwe-oxalic acid kunye ne-tartaric acid kuluncedo ekufakweni kwe-methanol, ngelixa i-citric acid inefuthe lokuthintela. Nangona kunjalo, uJ.Paul Chen et al. [35] bafumanise ukuba i-activated carbon eguqulwe nge-citric acid inokunyusa ukufunxwa kwee-ions zobhedu. ULin Tang et al. [36] waguqula i-activated carbon ethengiswayo ene-formic acid, i-oxalic acid kunye ne-aminosulfonic acid. Emva kokuguqulwa, indawo ethile yomphezulu kunye nomthamo we-pore zancitshiswa. Amaqela asebenzayo aqulethe i-oksijini afana ne-0-HC-0, C-0 kunye ne-S=0 enziwe phezu komphezulu wemveliso egqityiweyo, kwaye kwavela imijelo engalinganiyo kunye neekristale ezimhlophe. Umthamo we-adsorption ye-acetone kunye ne-isopropanol nawo wanda kakhulu.
Itekhnoloji yokuguqula isisombululo se-alkaline
Ezinye iingcali zisebenzise isisombululo se-alkaline ukwenza i-activation yesibini kwi-activated carbon. Faka isisombululo se-Na0H esenziwe ngamalahle esenziwe ekhaya ngesisombululo se-Na0H samanqanaba ahlukeneyo oxinzelelo ukulawula ulwakhiwo lwe-pore. Iziphumo zibonise ukuba uxinzelelo oluphantsi lwe-alkali lwalunceda ukwanda kwe-pore kunye nokwanda kwayo. Isiphumo esingcono sifunyenwe xa uxinzelelo lobunzima lwaluyi-20%. I-activated carbon yayinendawo ephezulu yomphezulu (681m2·g-1) kunye nomthamo we-pore (0.5916cm3·g-1). Xa uxinzelelo lobunzima be-Na0H ludlula i-20%, ulwakhiwo lwe-pore lwe-activated carbon luyatshatyalaliswa kwaye iiparameter zesakhiwo se-pore ziqala ukwehla. Oku kungenxa yokuba uxinzelelo oluphezulu lwesisombululo se-Na0H luya kutshabalalisa i-carbon skeleton kwaye inani elikhulu le-pore liya kuwa.
Ukulungiselela ikhabhoni esebenzayo esebenza kakhulu ngokuxuba i-polymer. Izinto zokuqala yayiyi-furfural resin kunye ne-furfuryl alcohol, kwaye i-ethylene glycol yayiyi-arhente eyenza i-pore. Ulwakhiwo lwe-pore lwalulawulwa ngokulungelelanisa umxholo wee-polymers ezintathu, kwaye kwafunyanwa into ene-porous enobukhulu be-pore phakathi kwe-0.008 kunye ne-5 μm. Ezinye iingcali ziye zangqina ukuba ifilimu ye-polyurethane-imide (PUI) inokufakwa kwi-carbon ukuze kufunyanwe ifilimu yekhabhoni, kwaye ulwakhiwo lwe-pore lunokulawulwa ngokutshintsha ulwakhiwo lwe-molecular ye-polyurethane (PU) prepolymer [41]. Xa i-PUI ishushu ukuya kwi-200°C, i-PU kunye ne-polyimide (PI) ziya kuveliswa. Xa ubushushu bonyango lobushushu bunyuka bufikelela kwi-400°C, i-PU pyrolysis ivelisa igesi, nto leyo ekhokelela ekwakhiweni kwesakhiwo se-pore kwifilimu ye-PI. Emva kwe-carbonization, kufunyanwa ifilimu yekhabhoni. Ukongeza, indlela yokuxuba i-polymer inokuphucula ezinye iipropati zomzimba neze-mechanical zezinto ukuya kwinqanaba elithile.
Itekhnoloji yokulawula ukusebenza kwe-Catalytic
Itekhnoloji yokulawula ukusebenza kwe-catalytic eneneni yindibaniselwano yendlela yokusebenza kweekhemikhali kunye nendlela yokusebenza kwegesi enobushushu obuphezulu. Ngokubanzi, izinto zeekhemikhali zongezwa kwizixhobo ezikrwada njengee-catalysts, kwaye ezi catalysts zisetyenziselwa ukunceda inkqubo yokwenza i-carbonization okanye yokwenza i-activation ukuze kufunyanwe izinto zekhabhoni ezinemingxuma. Ngokubanzi, iimetali ngokubanzi zineziphumo ze-catalytic, kodwa iziphumo ze-catalytic ziyahluka.
Enyanisweni, ngokuqhelekileyo akukho mda ucacileyo phakathi kommiselo wokusebenza kweekhemikhali kunye nomgaqo wokusebenza kwee-catalytic kwizixhobo ezinemingxuma. Oku kungenxa yokuba zombini ezi ndlela zongeza ii-reagents ngexesha lenkqubo yokwenza i-carbonization kunye neyokusebenza. Indima ethile yezi reagents imisela ukuba le ndlela ikwicandelo lokwenziwa kwee-catalytic.
Ulwakhiwo lwezinto ezineembobo zekhabhoni ngokwazo, iimpawu zomzimba nezekhemikhali ze-catalyst, iimeko ze-catalytic reaction kunye nendlela yokulayisha i-catalyst zonke zinokuba nefuthe elahlukileyo kwisiphumo sokulawula. Ukusebenzisa amalahle e-bituminous njengezinto eziluhlaza, i-Mn(N03)2 kunye ne-Cu(N03)2 njengee-catalysts zinokulungiselela izinto ezineembobo ezinee-metal oxides. Ubungakanani obufanelekileyo bee-metal oxides bunokuphucula i-porosity kunye nomthamo we-pore, kodwa iziphumo ze-catalytic zeentsimbi ezahlukeneyo zahlukile kancinci. I-Cu(N03)2 inokukhuthaza uphuhliso lwee-pores kuluhlu lwe-1.5 ~ 2.0nm. Ukongeza, ii-metal oxides kunye neetyuwa ezingaphiliyo eziqulethwe kuthuthu lwezinto eziluhlaza nazo ziya kudlala indima ye-catalytic kwinkqubo yokusebenza. U-Xie Qiang et al. [42] babekholelwa ukuba i-catalytic activation reaction yezinto ezifana ne-calcium kunye ne-iron kwizinto ezingaphiliyo inokukhuthaza uphuhliso lwee-pores. Xa umxholo wezi zinto zimbini uphezulu kakhulu, umlinganiselo wee-pores eziphakathi nezinkulu kwimveliso uyanda kakhulu.
Isiphelo
Nangona ikhabhoni esebenzayo, njengeyona nto isetyenziswa kakhulu kwikhabhoni eluhlaza enemingxuma, idlale indima ebalulekileyo kushishino nakubomi, isenamandla amakhulu okuphucula ukwandiswa kwezinto eziluhlaza, ukunciphisa iindleko, ukuphucula umgangatho, ukuphucula amandla, ukwandisa ubomi kunye nokuphucula amandla. Ukufumana izinto eziluhlaza zekhabhoni esebenzayo ezikumgangatho ophezulu nezingabizi kakhulu, ukuphuhlisa iteknoloji yokuvelisa ikhabhoni esebenzayo ecocekileyo nesebenzayo, kunye nokwenza ngcono kunye nokulawula ulwakhiwo lwemingxuma yekhabhoni esebenzayo ngokweendawo ezahlukeneyo zokusetyenziswa kuya kuba yindlela ebalulekileyo yokuphucula umgangatho weemveliso zekhabhoni esebenzayo kunye nokukhuthaza uphuhliso olusemgangathweni lweshishini lekhabhoni esebenzayo.
Ixesha leposi: Agasti-27-2024