I-Hielscher Ultrasound Technology

Sonocatalysis – Ultrasonically Assisted Catalysis

I-Ultrasonication ithinta i-reactivity ye-catalyst ngenkathi i-catalysis iphakanyisiwe ukufaka amandla okudlulisa nokusebenza kwamandla. Ku-catalysis ye-heterogeneous, lapho i-catalyst isendaweni ehlukile kuya ku-reactants, ukusabalalisa kwe-ultrasonic kwandisa indawo ekhona etholakalayo kuma-reactants.

Ingemuva ye-Catalysis

I-Catalysis inqubo lapho isilinganiso se-a ukuphendula kwamakhemikhali kwanda (noma wehlile) nge-catalyst. Ukukhiqizwa kwamakhemikhali amaningi kuhilela ukucubungula. Ithonya ekulingeni izinga lokuphendula lixhomeke emvamisa wokuxhumana we-reactants kwisinyathelo sokunquma isilinganiso. Ngokuvamile, izisusa zandisa izinga lokuphendula futhi zinciphisa amandla okuvuselela ngokuhlinzeka ngenye indlela yokusabela ekukhiqizeni umkhiqizo. Ngenxa yalokhu izisusa zithinta isakhi esisodwa noma ngaphezulu ukwakha izihambeli ezinikezela ngomkhiqizo wokugcina. Isinyathelo sokugcina sivuselela isisusa. Ngu ukunciphisa amandla okusebenza, ukushayisana okuningi kwamangqamuzana kunamandla okudingeka afinyelele esimweni sokuguquka. Kwesinye isikhathi izici ezisetshenziswayo zishintsha ukhetho lokuphendula kwamakhemikhali.

Umdwebo ubonisa umphumela wendlela yokwenza ama-chemical reaction X + Y ukukhiqiza iZ I umdwebo kuya ngakwesokudla kubonisa umphumela we-catalyst ekuphenduleni kwamakhemikhali X + Y ukukhiqiza iZ. I-catalyst inikeza enye indlela (eluhlaza) nge-activation ephansi ye-Energy Ea.

Imiphumela ye-Ultrasonication

Ukuphakama kwe-acoustic ku-liquide kusuka ku-approx. 110 kuya ku-0.15mm ngezikhathi eziphakathi kuka-18kHz no-10MHz. Lokhu kubaluleke ngaphezu kwezingqimba zamangqamuzana. Ngenxa yalesi sizathu, akukho ukuhlanganiswa okuqondile kwensimu ye-acoustic nge-molecule yezinhlobo zamakhemikhali. Imiphumela ye-ultrasonication yilezi zikhulu ngenxa yalokho cavitation ultrasonic ezitsheni. Ngakho-ke, i-catalysis eyasiza ultrasonically idinga okungenani eyodwa reagent ukuba ibe isigaba liquid. Ultrasonication inomthelela ekutheni i-catalysis engapheliyo neyama-homogeneous ngezindlela eziningi. Imiphumela yomuntu ngamunye ingakhuthazwa noma iyancishiswe ukulungisa ukuphakama kwe-ultrasonic nokucindezela ketshezi.

I-ultrasonic ihlakaza futhi imisa

Ukusabela kwamakhemikhali okubandakanya ama-reagents kanye ne-catalyst yesigaba esingaphezu kwesinye (catalyst heterogeneous catalysis) kunqunyelwe emngceleni wesigaba njengoba lena yindawo kuphela, lapho kutholakala khona i-reagent kanye ne-catalyst. Ukuvezwa kwama-reagents kanye nokwenzisana komunye nomunye yi-a isici esiyinhloko ekuphenduleni kwamakhemikhali amaningi amaningi. Ngenxa yalesi sizathu, indawo ecacile yomngcele wesigaba iba nomthelela ekwenzeni ama-chemical reaction reaction.

Imidwebo ibonisa ukuhlangana phakathi kobukhulu bezinhlayiyana kanye nendawoI-Ultrasonication iyindlela ephumelela kakhulu ye ukusabalalisa kwama-solids futhi for emulsification uketshezi. Ngokunciphisa usayizi we-particle / droplet, indawo ephelele yomngcele wesigaba iyanda ngesikhathi esifanayo. Umfanekiso ohlangothini lwesobunxele ubonisa ukuhlangana phakathi kobukhulu bezinhlayiyana kanye nomhlaba uma kwenzeka izinhlayiya ezincane noma amaconsi (Chofoza ukuze ubone ukubuka okukhulu!). Njengoba isakhiwo somngcele wesigaba sikhula futhi izinga lokuphendula kwamakhemikhali lithinta kanjani. Kwabaningi izinto zokwakha i-cavitation ye-ultrasonic zingenza izinhlayiya namaconsi ubukhulu obuhle kakhulu – ngokuvamile kakhulu ngaphansi kwe-nanometer eyi-100. Uma ukusabalalisa noma i-emulsion iba okungenani okwesikhashana okwesikhashana, ukusetshenziswa kwe Ama-ultrasonics angadingeka kuphela esigabeni sokuqala of the reaction chemical. I-reactor encane ye-ultrasonic yokuhlanganiswa kokuqala kwama-reagents kanye ne-catalyst ingaveza ama-particles amancane / amaconsi ngesikhathi esifushane kakhulu kanye nasezingeni eliphezulu lokugeleza. Kungasetshenziswa ngisho nakwabamemezeli be-viscous kakhulu.

I-Mass-Transfer

Lapho ama-reagents esabela emngceleni wesigaba, imikhiqizo ye-chemical response reaction iqoqa endaweni yokuxhumana. Lokhu kuvimbela amanye ama-molecule e-reagent ukuthi angahlanganyeli kulo mngcele wesigaba. Amandla okukhipha izingcingo ezibangelwa imifudlana ye-javitational kanye nomsakazo we-acoustical umphumela wokugeleza okuphazamisayo nokuthuthwa kwezinto ezivela ku-to particle noma endaweni ye-droplet. Endabeni yamaconsi, i-shear ephakeme ingabangela ukuba kube ne-coalescence nokubunjwa okulandelayo kwamaconsi amasha. Njengoba ukuphikisana kwamakhemikhali kuqhubeka ngokuhamba kwesikhathi, ukuvuselelwa ngokuphindaphindiwe, isib. Isigaba ezimbili noma ukuphindaphinda, kungadingeka ukuba ukwandisa ukuvezwa kwama-reagents.

Ukufaka amandla

I-cavitation ye-Ultrasonic iyindlela ehlukile faka amandla ekusebenzeni kwamakhemikhali. Inhlanganisela yejetshi ejubane yamanzi, ukucindezela okukhulu (>1000atm) namazinga aphezulu okushisa (>5000K), amazinga amaningi okushisa nokupholisa (>109Ks-1) kwenzeka endaweni yangakapheli ngesikhathi sokucindezela okungenalutho kwe-bubble cavitational. Kenneth Suslick says: "Cavitation is an extraordinary method of concentrating the diffuse energy of sound into a chemically usable form."

Khulisa ekusebenzeni kabusha

Ukuguguleka kwamakhemikhali kuma-particle ikhiqiza izindawo ezingaphenduliwe, eziphezulu kakhulu. Ukushisa okuphephile okufishane nokucindezela kunengxenye ukuchithwa kwamangqamuzana futhi ukwandise ukusebenza kabusha zezinhlobo eziningi zamakhemikhali. I-ultrasonic irradiation ingasetshenziselwa ukulungiselela ama-catalysts, isb ukukhiqiza ama-aggregates ama-particle-size particles. Lokhu kukhiqiza izici zokuqamba amorphous izinhlayiyana eziphezulu eziphezulu indawo. Ngenxa yalesi sakhiwo esiphezulu, lezo zakhizo zingahlukaniswa nemikhiqizo yokusabela (okusho ngokuhlunga).

Ultrasonic Cleaning

Ngokuvamile i-catalysis ihilela okungafunwa yi-imikhiqizo, ukungcola noma ukungcola kuma-reagents. Lokhu kungaholela ekwenzeni ukungcoliswa futhi kuqhutshwe phezu kwezinsimbi eziqinile. Ukuvuthwa kunciphisa ukukhanya okubonakalayo okusobala futhi ngaleyo ndlela kunciphisa ukusebenza kwayo. Akudingeki ukuthi kususwe noma phakathi nenqubo noma ngezikhathi zokuvuselela usebenzisa amanye amakhemikhali enqubo. I-Ultrasonication iyindlela ephumelelayo yokwenza ama-catalysts ahlanzekile noma asekela inqubo yokuvuselela kabusha. Ukuhlanzwa kwe-Ultrasonic cishe isicelo esivame kakhulu nesaziwayo se-ultrasonics. Ukufakelwa kwe-jets cavitational liquid kanye namagagasi okwethuka okufika ku-104i-atm ingakwazi ukudala amandla we-shear, ukuguguleka komhlabathi kanye nokukhishwa kwendawo. Ukuze uthole ama-particle ama-tile amahle, ukushayisana kwama-inter-particle okusheshayo kuholela ekukhuliseni komhlabathi futhi ngisho ukugaya nokugaya. Lezi zingxabano zingabangela ukushisa kwesikhashana kwendawo yangakini. 3000K. Suslick wabonisa, ukuthi ultrasonication ngempumelelo isusa izembatho ze-oxide. Ukukhishwa kwezingubo ezinjalo zokudlulela ngokweqile kuthuthukisa kakhulu izinga lokuphendula ngokuhlukahluka okuhlukahlukene (Suslick 2008). Ukusetshenziswa kwe-ultrasonics kusiza ekunciphiseni inkinga yokuqothula isakhi esiqinile esasakazeka ngesikhathi se-catalysis futhi sinomthelela ekuhlanzeni ngesikhathi senqubo yokuvuselela i-catalyst.

Izibonelo ze-Ultrasonic Catalysis

Kunezibonelo eziningi ze-catalysis ezisizwa ultrasonically kanye nokulungiselela ultrasonic of catalysts heterogeneous. Sincoma Sonocatalysis isihloko sikaKenneth Suslick isingeniso esibanzi. Hielscher inikeza reactors ultrasonic for ukulungiselela catalysts noma catalysis, njenge ukuguqulwa kwe-catalytic for the production of methylesters (ie fatty methylester = biodiesel).

Izinsiza ze-ultrasonic ze-Sonocatalysis

I-Ultrasonic Reactor enezinkampani ezingu-7 x 1kW ze-ultrasonic UIP1000hdI-Hielscher ikhiqiza amadivaysi e-ultrasonic ukuze kusetshenziswe noma yiliphi isilinganiso futhi a ezihlukahlukene izinqubo. Lokhu kuhlanganisa lab sonication emigodini encane kanye izimboni zezimboni kanye namaseli okugeleza. Ukuqala kokuhlola inqubo ebhalweni lebhu I-UP400S (ama-watts angu-400) kuhle kakhulu. Ingasetshenziselwa izinqubo ze-batch kanye ne-sonication encane. Ukuze kusetshenzwe inqubo nokusebenza kahle ngaphambi kokukala, sincoma ukusebenzisa i- UIP1000hd (1000 watts), njengoba lezi zinyunithi zivumelanisa kakhulu futhi imiphumela yokucubungula ingalinganiswa nanoma yikuphi amandla amakhulu. Ukuze uthole ukukhiqizwa okugcwele kwesilinganiso sinikeza amadivayisi we-ultrasonic kuze kube 10kW futhi 16kW amandla ultrasonic. Amaqoqo ezinyunithi eziningana ezinjalo anika amandla okucubungula kakhulu.

Sizojabula ukusekela inqubo yokuhlola, ukuthuthukisa nokwenza ngcono. Khuluma nathi mayelana nemishini efanele noma vakashela inqubo yethu ye laboratory.

Cela ulwazi oluthe xaxa!

Sicela ugcwalise leli fomu ukucela ulwazi oluthe xaxa mayelana ne-sonocatalysis kanye ne-catalysis eyayisizwa nge-ultrasonically.









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Izincwadi ku-Sonocatalysis ne-Ultrasonically Assisted Catalysis

Suslick, KS; Didenko, Y .; I-Fang, MM; I-Hyeon, T .; Kolbeck, KJ; McNamara, WB III; UMdlele, MM; Wong, M. (1999): I-Acoustic Cavitation Nemiphumela Yayo Yamakhemikhali, ku: Phil. I-Trans. Roy. I-Soc. A, 1999, 357, 335-353.

Suslick, KS; I-Skrabalak, SE (2008): "Sonocatalysis" In Handbook of Heterogeneous Catalysis, vol. 4; Ertl, G .; I-Knzinger, H .; I-Schth, F .; I-Weitkamp, ​​J., Eds ;; I-Wiley-VCH: Weinheim, 2008, iphe. 2006-2017.