I-Electrochemical Oxidation

Ngomqondo obanzi, i-electrochemical oxidation ibhekisela kuyo yonke inqubo ye-electrochemistry, ehilela ukusabela kwe-electrochemical okuqondile noma okungaqondile okwenzeka ku-electrode ngokusekelwe ezimisweni zokusabela kokunciphisa i-oxidation. Lokhu kusabela kuhloswe ukunciphisa noma ukususa ukungcola emanzini angcolile.

Kuchazwe kancane, i-electrochemical oxidation ibhekisela ngokukhethekile kunqubo ye-anodic. Kule nqubo, isisombululo se-organic noma ukumiswa kwethulwa esitokisini se-electrolytic, futhi ngokusebenzisa ukusetshenziswa kwamandla aqondile, ama-electron akhishwa ku-anode, okuholela e-oxidation yama-organic compounds. Ngaphandle kwalokho, izinsimbi ezine-valence ephansi zingafakwa i-oxidized kuma-ion ensimbi ane-valence ephezulu ku-anode, abese ebamba iqhaza ekufakweni kwe-oxidation yezinhlanganisela eziphilayo. Ngokuvamile, amaqembu athile asebenzayo ngaphakathi kwezinhlanganisela eziphilayo abonisa umsebenzi we-electrochemical. Ngaphansi kwethonya lenkambu kagesi, ukwakheka kwalawa maqembu asebenzayo kuba nezinguquko, ukuguqula izakhiwo zamakhemikhali ze-organic compounds, ukunciphisa ubuthi bazo, futhi kuthuthukise ukubola kwazo.

I-Electrochemical oxidation ingahlukaniswa ngezinhlobo ezimbili: i-oxidation eqondile kanye ne-oxidation engaqondile. I-oxidation eqondile (i-electrolysis eqondile) ihilela ukukhishwa okuqondile kokungcola emanzini angcolile ngokuwafaka nge-oxidizing ku-electrode. Le nqubo ihlanganisa kokubili izinqubo ze-anodic ne-cathodic. Inqubo ye-anodic ihilela ukukhishwa kwe-oxidation yezinto ezingcolisayo endaweni ye-anode, kuziguqule zibe izinto ezinobuthi obuncane noma izinto ezingabola kakhulu, ngaleyo ndlela zehlise noma ziqede ukungcola. Inqubo ye-cathodic ihilela ukuncishiswa kokungcola endaweni ye-cathode futhi isetshenziselwa ngokuyinhloko ukunciphisa nokususwa kwama-halogenated hydrocarbons kanye nokutholwa kwezinsimbi ezisindayo.

Inqubo ye-cathodic ingabuye ibizwe ngokuthi ukuncishiswa kwe-electrochemical. Kubandakanya ukudluliswa kwama-electron ukuze kuncishiswe ama-ion ensimbi esindayo afana ne-Cr6+ ne-Hg2+ ezifundeni zawo eziphansi ze-oxidation. Ukwengeza, inganciphisa izinhlanganisela eziphilayo ezine-chlorine, iziguqule zibe izinto ezinobuthi obuncane noma ezingenabo ubuthi, ekugcineni kuthuthukise ukubola kwazo:

R-Cl + H+ + e → RH + Cl-

I-oxidation engaqondile (i-electrolysis engaqondile) ihlanganisa ukusetshenziswa kwe-electrochemically oxidizing noma ama-ejenti anciphisayo njengama-reactants noma ama-catalyst ukuguqula ukungcola kube izinto ezinobuthi obuncane. I-electrolysis engaqondile ingabuye ihlukaniswe ibe izinqubo ezihlehliswayo nezingenakuhlehliswa. Izinqubo ezibuyiseleka emuva (i-mediated electrochemical oxidation) zibandakanya ukukhiqizwa kabusha nokugaywa kabusha kwezinhlobo ze-redox phakathi nenqubo ye-electrochemical. Izinqubo ezingahlehliseki, ngakolunye uhlangothi, zisebenzisa izinto ezikhiqizwe ekuphenduleni kwe-electrochemical okungenakuhlehliswa, njengama-oxidizing agents afana ne-Cl2, i-chlorates, ama-hypochlorite, i-H2O2, ne-O3, ukuze kufakwe i-organic compounds. Izinqubo ezingabuyiseleki emuva zingase futhi zikhiqize izinto ezimaphakathi ezine-oxidative kakhulu, okuhlanganisa ama-electron axazululiwe, ·HO radicals, ·HO2 radicals (hydroperoxyl radicals), kanye ·O2- radicals (superoxide anions), angasetshenziswa ukucekela phansi nokuqeda izinto ezingcolisayo njenge-cyanide, phenols, I-COD (Chemical Oxygen Demand), kanye nama-S2- ions, agcina ewaguqule abe izinto ezingenabungozi.

Esimeni se-anodic oxidation eqondile, ukugxila okuphansi kwe-reactant kungakhawulela ukusabela kwe-electrochemical surface ngenxa yemikhawulo yokudlulisa okukhulu, kuyilapho lo mkhawulo ungekho ezinqubweni ze-oxidation ezingaqondile. Phakathi nezinqubo zombili ze-oxidation eziqondile nezingaqondile, ukusabela okusemaceleni okuhilela ukukhiqizwa kwegesi i-H2 noma i-O2 kungase kwenzeke, kodwa lokhu kusabela okuseceleni kungalawulwa ngokukhethwa kwezinto zokwenziwa kwama-electrode nokulawula okungase kube khona.

I-Electrochemical oxidation itholakale iphumelela ekwelapheni amanzi angcolile ngokugxila okuphezulu kwe-organic, ukwakheka okuyinkimbinkimbi, inqwaba yezinto eziphikisayo, nemibala ephezulu. Ngokusebenzisa ama-anode anomsebenzi we-electrochemical, lobu buchwepheshe bungakhiqiza ngempumelelo ama-oxidative hydroxyl radicals. Le nqubo iholela ekuboleni kokungcola kwemvelo okuqhubekayo kube yizinto ezingenabo ubuthi, izinto ezibolayo kanye namaminerali aphelele abe yinhlanganisela efana ne-carbon dioxide noma carbonates.