Ucwaningo Ngokusabela phakathi kweSilver Sulfide ne-Sodium Cyanide

1. Isingeniso

Ukusabela phakathi Isiliva sulfide (\(Ag_2S \)) kanye I-sodium cyanide (\(NaCN \)) inemithelela ebalulekile emikhakheni eyahlukene, ikakhulukazi ekukhishweni kwesiliva kunsimbi yayo. Ukuqonda lokhu kusabela kubalulekile ekuthuthukiseni izinqubo zezimboni kanye nokuqonda okujulile kokulingana kwamakhemikhali kanye ne-kinetics ezinhlelweni eziyinkimbinkimbi.

2. Izimiso Zokusabela

2.1 I-Chemical Equation

Ukusabela phakathi kwesiliva sulfide kanye I-Sodium Cyanide ingamelwa

b isibalo samakhemikhali esilandelayo lapho kukhona umoya:\(2Ag_2S + 8NaCN + O_2 + 2H_2O = 4Na[Ag(CN)_2] + 4NaOH + 2S\)

Kule mpendulo, i-silver sulfide isabela nayo i-sodium cyanide. Isiliva ku-sulfide yesiliva yakha i-ion eyinkimbinkimbi, isiliva i-cyanide i-complex ion \([Ag(CN)_2]^{-} \), kuyilapho isulfure esiliva sulfide i-oxidized ukuze ibe sulphur eyisisekelo. I-oxygen emoyeni ibamba iqhaza ekuphenduleni, isebenza njenge-oxidizing agent.

2.2 Ukwakhiwa kwe-Ion eyinkimbinkimbi

Isiliva linomkhuba oqinile wokwenza ama-ion ayinkimbinkimbi ngama-ion e-cyanide. Ukwakheka kwe-\([Ag(CN)_2]^{-} \) kuqhutshwa ukuzinza okuphezulu kwale ion eyinkimbinkimbi. Ukulinganisa okungaguquki kokwakhiwa kwe- \([Ag(CN)_2]^{-} \) kukhulu uma kuqhathaniswa, okusho ukuthi ukusabela kwama-ion esiliva nama-ion e-cyanide ukuze akhe le nkimbinkimbi kuhle kakhulu. I-ion eyinkimbinkimbi \([Ag(CN)_2]^{-}\) incibilika kakhulu emanzini uma iqhathaniswa nesiliva sulfide, engancibiliki. Lo mehluko wokuncibilika uyisici esibalulekile kunqubo yonke yokusabela.

2.3 I-Oxidation yesibabule

Isulfure ku-silver sulfide isesimweni se--2 oxidation. Ngesikhathi sokusabela nge-sodium cyanide phambi komoya, isulfure i-oxidized. I-oxygen evela emoyeni inikeza amandla oksijini. I-oxidation yesibabule kusuka ku -2 kuya ku-0 (i-elemental sulfure) iyingxenye ebalulekile yendlela yokusabela. Indlela yokusabela ye-oxidation yesulfure ihilela uchungechunge lwezinyathelo zokudlulisa ama-electron, ezihlobene eduze nesilinganiso sokusabela okuphelele kanye nokwakhiwa kwemikhiqizo.

3. Izimo zokusabela

3.1 Ukucatshangelwa kwe-Thermodynamic

I-Thermodynamically, ukusabela okuqondile kwesiliva sulfide ne-sodium cyanide ngaphandle kokuba khona kwe-ejenti eyenza i-oxidizing njengomoya kunoshintsho oluhle lwamandla amahhala we-Gibbs (\(\Delta G>0\)). Lokhu kubonisa ukuthi ukusabela akuzenzeki ngaphansi kwezimo ezijwayelekile. I-equilibrium constant (\(K\)) yokusabela \(Ag_2S + 4NaCN\rightleftharpoons 2Na[Ag(CN)_2]+Na_2S\) incane uma kuqhathaniswa. Nokho, lapho kwethulwa umoya-mpilo, ukusabela okuphelele kuba ngokuzenzekelayo. I-oxidation yesibabule nge-oxygen inikeza amandla okushayela ukunqoba ukungenzi ngokuzenzekelayo kokusabela kokuqala phakathi kwe-silver sulfide ne-sodium cyanide.

3.2 Izidingo zokugxilisa ingqondo

Ukuze ukusabela kuqhubeke ngokuphumelelayo, ukuhlushwa okwanele kwe-sodium cyanide kuyadingeka. Njengoba isiliva sulfide ingancibiliki emanzini, i-cyanide ions ephezulu iyadingeka ukuze ihlanganiswe nama-ion esiliva aphuma kancane ku-silver sulfide. Izibalo zibonise ukuthi \(0.1mol\) ye \(Ag_2S\) ukuze incibilike \(1L\) yesixazululo \(NaCN\)), ubuncane bokugxila \(NaCN\) obudingekayo bucishe bube ngu\(12.97mol/L\). Lesi sidingo sokugxila okuphezulu kungenxa yokuncibilika okuphansi kwe-sulfide yesiliva kanye nesidingo sokushintsha ukulingana kwe-complex - ukwakheka ukusabela ekwakhekeni kwesiliva - i-cyanide complex ion.

3.3 Izinga lokushisa kanye nengcindezi

Nakuba ukusabela phakathi kwe-silver sulfide ne-sodium cyanide kungase kwenzeke ekamelweni lokushisa, ukwanda kwezinga lokushisa ngokuvamile kungasheshisa izinga lokusabela. Amazinga okushisa aphakeme akhuphula amandla e-kinetic ama-molecule asabelayo, okuholela ekushayisaneni okuvamile nokunamandla. Kodwa-ke, amazinga okushisa aphakeme kakhulu angase abangele ukusabela okuseceleni, njengokubola kwezinhlanganisela ze-cyanide. Ingcindezi ayinawo umthelela oqondile obalulekile kulokhu kusabela ngaphansi kwezimo ezijwayelekile, njengoba kuwukusabela esixazululweni esinamanzi hhayi ukusabela kwesigaba segesi lapho izinguquko zengcindezi zizoba nomthelela ogqame kakhudlwana.

4. I-Rection Kinetics

4.1 Ukunqunywa Kwezinga Lokusabela

Izinga lokusabela kwesiliva sulfide nge-sodium cyanide linganqunywa ngezindlela zokuhlola. Ngokukala ushintsho ekugxilweni kwezinto ezisabelayo (njengesiliva sulfide noma i-sodium cyanide) noma imikhiqizo (njengesiliva - i-cyanide complex ion noma isulfure) ngokuhamba kwesikhathi, izinga lokusabela lingabalwa. Isibonelo, ekuhlolweni kwe-batch reactor, amasampula angathathwa ngezikhathi ezithile, futhi ukugxiliswa kwe-silver - cyanide complex ion kusixazululo kungalinganiswa kusetshenziswa amasu okuhlaziya afana ne-spectrophotometry noma i-ion - electrode ekhethiwe. Izinga lokwakheka kwe-silver - cyanide complex ion libe selisetshenziswa ukubala inani lokusabela eliphelele.

4.2 Linganisa - Ukunquma Izinyathelo

Indlela yokusabela yesiliva sulfide cyanidation iyinkimbinkimbi futhi ihilela izinyathelo eziningi. Izinga - isinyathelo sokunquma cishe isinyathelo esinensa kakhulu ekulandeleni kokusabela. Esinye sezinyathelo ezibalulekile ukuchithwa kwe-sulfide yesiliva, okubandakanya ukukhululwa kwama-ion esiliva nama-sulfur ions. Ukuhlanganiswa kwama-ion esiliva ane-cyanide ion kuyashesha uma kuqhathaniswa nokuchithwa kwe-sulfide esiliva. I-oxidation yesibabule nge-oxygen nayo idlala indima ebalulekile ekuphenduleni izinga lokuphendula. Uma ukunikezwa komoya-mpilo kunomkhawulo, kungase kube isilinganiso - isici esinqumayo. Ngaphezu kwalokho, ukusakazeka kwama-molecule asabelayo (njengama-ion e-cyanide nomoya-mpilo) endaweni yezinhlayiya ze-silver sulfide nakho kungathinta izinga lokusabela, ikakhulukazi ezimeni lapho ubukhulu bezinhlayiyana ze-sulfide esiliva bukhulu.

4.3 Ukumodela Kwezibalo

Amamodeli ezibalo athuthukisiwe ukuchaza i-kinetics yokusabela ye-silver sulfide cyanidation. Imodeli eyodwa evame ukusetshenziswa yimodeli enciphayo - eyinhloko. Le modeli ithatha ukuthi ukusabela kwenzeka ebusweni bezinhlayiya eziqinile zesiliva sulfide, futhi njengoba ukusabela kuqhubeka, umnyombo we-sulfide yesiliva engaphenduliwe uyashwabana. Imodeli icabangela izici ezifana nokusatshalaliswa kwama-reactants ngongqimba lomkhiqizo (isulfure neminye imikhiqizo yokusabela engase yakheke phezu kwezinhlayiya ze-silver sulfide), izinga lokusabela kwamakhemikhali endaweni engaphezulu, kanye nokulingana kokuyinkimbinkimbi esigabeni sesixazululo. Ngokusebenzisa le modeli, kungenziwa izibikezelo mayelana nezinga lokusabela ngaphansi kwezimo ezihlukene, njengokugxila okuhlukahlukene kwe-sodium cyanide nomoya-mpilo, usayizi wezinhlayiyana zesiliva sulfide, nezinga lokushisa. Imiphumela yokuhlolwa ngokuvamile itholwe ivumelana kahle nezibikezelo zamamodeli anjalo ezibalo.

I-5. Izicelo

5.1 Ukukhishwa kwesiliva ku-Ores

Ukusabela phakathi kwe-silver sulfide ne-sodium cyanide kusetshenziswa kakhulu embonini yezimayini ukuze kukhishwe isiliva ku-sulfide ores. Enqubweni evamile ye-cyanidation, i-ore echotshoziwe enesiliva iphathwa ngesisombululo se-sodium cyanide. Isiliva sulfide ku-ore ihlangana ne-sodium cyanide ukwenza isiliva encibilikayo - i-cyanide complex. Ngemuva kokusabela, isisombululo esiqukethe isiliva - i-cyanide complex sihlukaniswa nezinsalela eziqinile. Isiliva singabe sesitholwa esixazululweni ngezindlela ezihlukahlukene, njengokunciphisa nge-ejenti yokunciphisa efanelekile (isb., uthuli lwezinki). Le nqubo iphumelela kakhulu futhi ingenye yezindlela ezivame ukusetshenziswa ezilinganisweni ezinkulu Ukukhishwa kwesiliva.

5.2 Ukucatshangelwa kwemvelo

Kodwa-ke, ukusetshenziswa kwe-sodium cyanide enqubweni yokukhipha isiliva kuphakamisa ukukhathazeka kwemvelo. I-Cyanide iwubuthi obuphezulu, futhi noma yikuphi ukuvuza noma ukulahlwa okungafanele kwe-cyanide - equkethe izixazululo kungaba nomthelela omubi kwezemvelo. Ngakho-ke, imithetho eqinile yezemvelo ikhona ukuze kuqinisekiswe ukuphathwa ngokuphephile nokulahlwa kwe-cyanide embonini yezimayini. Izinkampani eziningi zezimayini futhi zenza ezinye izindlela zokunciphisa ukusetshenziswa kwe-cyanide noma ukwelapha i-cyanide - equkethe imfucuza ngempumelelo. Naphezu kwalezi zinselele, ukusabela phakathi kwe-silver sulfide ne-sodium cyanide kusalokhu kuyinqubo ebalulekile embonini yezimayini zesiliva ngenxa yokusebenza kahle kwayo ekukhishweni kwesiliva.

6. Isiphetho

Ukusabela phakathi kwe-silver sulfide ne-sodium cyanide kuyinqubo yamakhemikhali eyinkimbinkimbi esebenzisa okubalulekile ekukhishweni kwesiliva. Ukuqonda izimiso zokusabela, izimo, i-kinetics, kanye nezicelo kubalulekile ukuze kuthuthukiswe izinqubo zezimboni kanye nokubhekana nokukhathazeka kwemvelo okuhlobene nokusetshenziswa kwe-cyanide. Ucwaningo olwengeziwe kule ndawo lungase lugxile ekuthuthukiseni izimo zokusabela ezisebenza kahle, ukuthuthukisa ukukhetha kokusabela, kanye nokuthola ezinye izindlela zokushintsha noma ukunciphisa ukusetshenziswa kwe-cyanide ekukhishweni kwesiliva.