Electrochemical Oxidation

Ngengqiqo ebanzi, i-electrochemical oxidation ibhekisela kuyo yonke inkqubo ye-electrochemistry, ebandakanya ukuphendula ngokuthe ngqo okanye okungathanga ngqo kwe-electrochemical reactions okwenzeka kwi-electrode ngokusekelwe kwimigaqo yokunciphisa i-oxidation-reduction reactions. Ezi ntshukumo zijolise ekunciphiseni okanye ekususeni izinto ezingcolisa amanzi kumanzi amdaka.

Ukuchazwa kancinci, i-electrochemical oxidation ibhekisa ngokukodwa kwinkqubo ye-anodic. Kule nkqubo, isisombululo se-organic okanye ukumiswa singeniswa kwiseli ye-electrolytic, kwaye ngokusetyenziswa kwangoku ngokuthe ngqo, ii-electron zikhutshwa kwi-anode, ezikhokelela kwi-oxidation ye-organic compounds. Ngenye indlela, iintsimbi eziphantsi kwe-valence zinokuthi zenziwe nge-oxidized kwi-ion zetsimbi eziphezulu ze-valence kwi-anode, ezithatha inxaxheba kwi-oxidation ye-organic compounds. Ngokuqhelekileyo, amaqela athile asebenzayo ngaphakathi kweekhompawundi eziphilayo abonisa umsebenzi we-electrochemical. Ngaphantsi kwefuthe lentsimi yombane, isakhiwo lala maqela asebenzayo senza utshintsho, ukuguqula iimpawu zeekhemikhali ze-organic compounds, ukunciphisa ubuthi babo, kunye nokuphucula i-biodegradability yabo.

I-oxidation ye-Electrochemical ingahlelwa kwiindidi ezimbini: i-oxidation ngqo kunye ne-oxidation engathanga ngqo. I-oxidation ngokuthe ngqo (i-electrolysis ngqo) ibandakanya ukususwa ngokuthe ngqo kwezinto ezingcolileyo kumanzi amdaka ngokuzikhupha kwi-electrode. Le nkqubo ibandakanya zombini iinkqubo ze-anodic kunye ne-cathodic. Inkqubo ye-anodic ibandakanya i-oxidation yezinto ezingcolileyo kumphezulu we-anode, ukuziguqulela kwizinto ezinobuthi obuncinci okanye izinto ezinokonakala kakhulu kwi-biodegradable, ngaloo ndlela ukunciphisa okanye ukuphelisa ukungcola. Inkqubo ye-cathodic ibandakanya ukuncitshiswa kwezinto ezingcolileyo kwi-cathode surface kwaye isetyenziselwa ukunciphisa kunye nokususwa kwe-halogenated hydrocarbons kunye nokubuyiselwa kwesinyithi esinzima.

Inkqubo ye-cathodic inokubizwa ngokuba yi-electrochemical reduction. Kubandakanya ukuhanjiswa kwee-electron ukunciphisa i-ion zensimbi ezinzima ezifana ne-Cr6 + kunye ne-Hg2 + kwiindawo zabo eziphantsi ze-oxidation. Ukongeza, inokunciphisa iikhompawundi ze-chlorinated organic, iziguqule zibe zizinto ezinetyhefu encinci okanye ezingekho tyhefu, ekugqibeleni ziphucule ukubola kwazo:

R-Cl + H+ + e → RH + Cl-

I-oxidation engathanga ngqo (i-electrolysis engathanga ngqo) ibandakanya ukusetyenziswa kwe-electrochemically generated oxidizing okanye ii-agent zokunciphisa njenge-reactants okanye i-catalysts ukuguqula ukungcola kwizinto ezinobuthi obuncinci. I-electrolysis engathanga ngqo inokuphinda ihlelwe kwiinkqubo eziguqulwayo nezingenakuguqulwa. Iinkqubo ezibuyiselwa umva (i-mediated electrochemical oxidation) ibandakanya ukuhlaziywa kunye nokuhlaziywa kweentlobo ze-redox ngexesha lenkqubo ye-electrochemical. Iinkqubo ezingenakujikwa, kwelinye icala, zisebenzisa izinto eziveliswa kwiimpendulo ze-electrochemical ezingenakuguqulwa, ezifana nee-oxidizing agents ezifana ne-Cl2, i-chlorates, i-hypochlorites, i-H2O2, kunye ne-O3, ukwenza i-oxidize ikhompawundi eziphilayo. Iinkqubo ezingenakujikwa zisenokwenza imidibaniso ene-oxidative ephezulu, kuqukwa nee-electron ezinyibilikisiweyo, ·HO radicals, ·HO2 radicals (hydroperoxyl radicals), kunye ·O2- radicals (superoxide anions), ezinokusetyenziswa ukuthobisa nokuphelisa izinto ezingcolisa umzimba ezifana necyanide, phenols, I-COD (i-Chemical Oxygen Demand), kunye ne-S2- ions, ekugqibeleni iziguqule zibe zizinto ezingenabungozi.

Kwimeko ye-anodic oxidation ngokuthe ngqo, ukugxilwa kwe-reactant ephantsi kunokunciphisa i-electrochemical surface reaction ngenxa yemida yokudlulisa ubuninzi, ngelixa lo mda ungekho kwiinkqubo ze-oxidation ezingathanga ngqo. Ngethuba leenkqubo ze-oxidation ezithe ngqo kunye nezingathanga ngqo, iimpendulo zecala ezibandakanya isizukulwana se-H2 okanye i-O2 yegesi ingenzeka, kodwa ezi mpendulo zecala zingalawulwa ngokukhethwa kwezinto ze-electrode kunye nokulawula okunokwenzeka.

I-oxidation ye-Electrochemical ifunyaniswe iyasebenza ekunyangeni amanzi amdaka anoxinzelelo oluphezulu lwe-organic, ukwakheka okuntsokothileyo, inkitha yezinto eziphikisayo, kunye nemibala ephezulu. Ngokusebenzisa i-anodes ngomsebenzi we-electrochemical, obu buchwepheshe bunokuvelisa ngokufanelekileyo i-oxidative hydroxyl radicals. Le nkqubo ikhokelela ekuboleni kongcoliseko lwendalo oluzingileyo lube zizinto ezingeyotyhefu, ezonakaliswa yi-biodegradable kunye ne-mineralization yazo epheleleyo kwiikhompawundi ezifana nekharbon diokside okanye i-carbonates.