Tšebeliso ea Sodium Cyanide ka Khauta e Nkiloeng e Hlalositsoe

Nakong ea ho ntša khauta metsoakong ea cyanide, Sodium cyanide e sebelisoa ka litsela tse 'maloa. Sodium cyanide ke sesebelisoa se sebelisoang haholo ho ntšeng khauta, 'me ka khopolo-taba, ho hlokahala ligrama tse 0.5 feela tsa Sodium Cyanide ho ntšeng gram e le' ngoe ea khauta. Leha ho le joalo, limela tse ngata tsa cyanidation ea khauta, tšebeliso ea cyanide e phahame haholo, hangata e feta lipalo tsa khopolo-taba ka makhetlo a 50 ho isa ho a 100.

Mabaka a ka sehloohong a tlatsetsang tšebelisong e phahameng ea cyanide ts'ebetsong ea cyanidation ea khauta a kenyelletsa:

1. Tšebeliso ea Cyanide Ts'ebetsong ea Khauta ea Khauta

Dimela tsa cyanide di ntse di sebedisa sodium cyanide ho qhala kgauta ho tswa leoreng e le ho fumana kgauta ho tswa leachate. Dikarabelo tsa dikhemikhale tse amehang ke tse latelang:

• [2Au+4NaCN+O2+2H2O→2Na[Au(CN)2]+2NaOH+H2O2]

• [ 2Au+4NaCN+H2O2→2Na[Au(CN)2]+2NaOH]

Ho latela karabelo ea electrochemical, hoa tsebahala hore ho qhaqha gram e le 'ngoe ea khauta ho hloka hore ho sebelisoe ligrama tse 1 tsa sodium cyanide.

2. Tšebeliso ea Cyanide ka Reactions le Associated Base Metals

(1) Majwe a mang a kgauta a na le diminerale tse amanang le ona tse kang pyrite, magnetite, chalcopyrite, diminerale tsa sulfate, hydroxides le di-oxide. Nakong ya ho sila, phofo ya tshepe e a hlahiswa, e arabelang butle le sodium cyanide, e leng se eketsang tshebediso ya cyanide . Dikarabelo ke tse latelang:

• [ FeS2+NaCN→FeS+NaCNS]

• [ Fe(OH)2+2NaCN→Fe(CN)2+2NaOH]

• [ Fe+6NaCN+2H2O→Na4Fe(CN)6+2NaOH+H2↑]

• [S+NaCN→NaCNS]

(2) Haeba ore ea khauta e na le mefuta e fapaneng ea liminerale tsa koporo, li tla boela li sebetsane le sodium cyanide ho etsa li-complexes tsa koporo tsa cyanide, tse jang cyanide nakong eo. Likarabo ke tse latelang:

• [ 2CuSO4+4NaCN→Cu2(CN)2+2Na2SO4+(CN)2↑]

• [ 2Cu2S+4NaCN+2H2O+O2→Cu2(CN)2+Cu2(CNS)2+4NaOH]

Ka lebaka la ts'ebetso e matla ea sodium cyanide e nang le liminerale tse ngata tsa koporo, ka kakaretso, ligrama tse 2.3 ho isa ho tse 3.4 tsa cyanide li hlokahala ho qhaqha gram e le 'ngoe ea koporo.

(3) Haeba ore ea pele ea khauta e na le sphalerite kapa smithsonite, li tla boela li itšoara ka sodium cyanide ho etsa zinc cyanide le carbonates. Likarabo ke tse latelang:

• [ ZnS+4NaCN→Na2[Zn(CN)4]+Na2S]

• [ ZnCO3+4NaCN→Na2Zn(CN)4+Na2CO3]

(4) Haeba ore ea khauta e na le arsenopyrite, mercury, selenium, tellurium, joalo-joalo, ba tla boela ba itšoara ka sodium cyanide. Ha 'mele oa ore o e-na le majoe a nang le carbonaceous, haholo-holo a ruileng ka carbon organic, adsorption ea cyanide e ba matla, e leng ho etsang hore cyanide leaching ea khauta e be thata le ho feta.

3. Hydrolysis ea Cyanides

Tharollong, li-cyanide li feta maemong a fapaneng a hydrolysis ho latela pH, 'me bongata ba hydrogen cyanide e hlahisoang bo amana le alkalinity ea tharollo. Karabelo e ka emeloa ka tsela e latelang:

• [NaCN + H2O → NaOH + HCN↑]

• [CN⁻ + 2H2O → HCOO⁻ + NH3]

Ka mor'a hydrolysis, karolo ea cyanide e hlahisa hydrogen cyanide, ha karolo e 'ngoe e le oxidatively hydrolyzed, butle-butle e hlahisa formic acid le ammonia. Ka 100 ° C, CN⁻ e lahleheloa ke 50%, 'me ka 130 ° C, e lahleheloa ke 85%.

Ts'ebetsong ea cyanidation bakeng sa merafo ea khauta, hydrogen cyanide ke khase e chefo haholo. Haeba e sa laoloe hantle, e ka lebisa ts'ebelisong e eketsehileng ea NaCN, ho phahamisa litšenyehelo tsa tlhahiso, le ho baka tšilafalo ea tikoloho, hammoho le ho beha likotsi tsa bophelo ho basebetsi. Palo ea HCN e hlahisoang e fapana ho ea ka pH ea tharollo: ho pH 10.5. ke 6.1% feela ea hydrogen cyanide e hlahisoang; ho pH 10. e nyolohela ho 17%; ka pH 9.5. e fihla ho 39.2%; le pH 9.0. ke 67.1%. Ka hona, limela tsa khauta tsa CIP (Carbon-in-Pulp), pH hangata e fetoloa ho ba lipakeng tsa 11 le 12 ho laola hydrolysis ea cyanides.

4. The oxidation ea cyanide (CN-) ka oksijene e qhibilihisitsoeng (O2)

Ho matlafatsa sekhahla sa ho qhibiliha ha khauta, ka bobeli CN- le O2 li tlameha ho ameha karabelong. Mocheso oa kamore le khatello, ho qhibiliha ho holimo ha oksijene ke 8.2 mg/L. Ho eketsoa ha motsoako o matla oa oxidizing ho ka eketsa khatello ea oksijene ka tharollo, ho potlakisa haholo ts'ebetso ea ho tsoa. Leha ho le joalo, karo-karolelano ea oksijene ho cyanide e tlameha ho leka-lekana; ho seng joalo, sekhahla sa leaching se ka fokotseha. Oksijene e qhibilihisitsoeng e kopana le cyanide ho etsa cyanate, e tsitsitseng metsoakong ea alkaline. Leha ho le jwalo, ka pH e ka tlase ho 7. e hydrolyzes ho hlahisa ammonia le bicarbonate. Li-equations tsa reaction ke tse latelang:

• [1/2 O2 + CN– → (CNO)–]

• [(CNO)– + 2 H2O → HCO3– + NH3]

Ka hona, karabelo ena e ka lebisa ts'ebelisong ea cyanide nakong ea ts'ebetso ea leaching kapa electrolysis.

5. Adsorption ea Cyanide ka Clay

Nakong ea ts'ebetso ea cyanidation, sulfide ea tšepe e ka har'a ore e hlahisa tšepe ea hydroxide, ha li-silicates tsa ore li etsa silika ea colloidal sebakeng sa alkaline. Lintho tsena ka bobeli li na le bokhoni bo itseng ba ho adsorb cyanide, e lebisang tahlehelong ea cyanide hammoho le masala a leaching.

6. Tšebeliso ea cyanide ke lintho tse ling

(1) Ha slurry e tsosoa 'me e tletse moea, CO2 e tla ba teng ka tharollo. CO2 e tla boela e sebetsane le cyanide.

• [2NaCN+CO2+H2O→Na2CO3+2HCN↑]

(2) Liminerale tsa sulfide tse kang pyrite ore ea pele li arabela ka oksijene e qhibilihisitsoeng (O2) ka har'a makhasi a ore, 'me li-sulfite tse hlahisoang le sulfate le tsona li tla itšoara ka cyanide.

• [FeS+2O2→FeSO4]

• [FeSO4+6NaCN→Na4Fe(CN)6+Na2SO4]

Palo e nyane ea CaO kapa Ca(OH)2 e ka eketsoa pele ho leaching ho fokotsa asiti le ho thibela karabelo e kaholimo ho etsahala.

ha re phethela

Lintlha tse ka holimo ke lintlha tsa 6 tsa tšebeliso ea cyanide ts'ebetsong ea khauta ea cyanidation. Ntle le cyanide e hlokahalang bakeng sa ho qhibiliha ho tloaelehileng ha khauta, ho na le lisebelisoa tse ngata tseo e seng tsa bohlokoa, joalo ka karabelo ea rona le liminerale tse ling tse amanang le tsona, self-hydrolysis, joalo-joalo. 

Haeba u na le lipotso mabapi le litaba tse ka holimo, kapa u batla ho tseba, u ka ikopanya le litšebeletso tsa bareki ba inthaneteng kapa ua fana ka molaetsa, re tla ikopanya le uena kapele kamoo ho ka khonehang!