Nri Sodium Cyanide na Mwepụta ọla edo kọwara

N'usoro ịwepụta ọla edo na ogige cyanide. sodium cyanide a na-eri ya n'ọtụtụ ụzọ. Sodium cyanide bụ ihe a na-ejikarị eme ihe onye nlekọta leaching na mmịpụta ọla edo, na usoro iwu, naanị 0.5 grams nke sodium cyanide a chọrọ iji leach 1 gram ọla edo. Agbanyeghị, n'ọtụtụ osisi cyanidation ọla edo, oriri cyanide n'ezie na-arị elu nke ukwuu, na-enwekarị mgbako usoro iwu site na 50 ruo 100 ugboro.

Isi ihe na-enye aka na oke oriri nke cyanide na usoro cyanidation ọla edo -agụnye:

1. Oriri nke Cyanide na Usoro Mgbasa ọla edo

A na-eji osisi Cyanide eme ihe sodium cyanide igbari ọla-edo site na ọla iji nwetaghachi ọla edo n'ime leachate. Mmeghachi omume kemịkalụ metụtara bụ ndị a:

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

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

Site na mmeghachi omume electrochemical, a maara na ịgbari gram ọla edo chọrọ 1 grams nke sodium cyanide.

2. Oriri nke Cyanide na mmeghachi omume na Associated Base Metals

(1) Ụfọdụ ọla edo nwere ihe ndị metụtara ya dị ka pyrite, magnetite, chalcopyrite, mineral sulfate, hydroxides, na oxides. N'oge ọgba aghara ahụ, a na-emepụta ntụ ntụ ígwè, nke na-eji nwayọọ nwayọọ na-emeghachi omume na sodium cyanide, na-abawanye oriri cyanide. Mmeghachi omume ndị a bụ:

• [FeS2+NaCN→FeS+NaCNS]

• [Fe(OH)2+2NaCN→Fe(CN)2+2NaOH]

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

• [S+NaCN→NaCNS]

(2) Ọ bụrụ na ọla edo nwere ụdị ọla kọpa dị iche iche, ha ga-emeghachikwa omume na sodium cyanide iji mepụta ogige cyanide ọla kọpa, na-eri cyanide na usoro ahụ. Mmeghachi omume ndị a bụ:

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

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

N'ihi mmeghachi omume siri ike nke sodium cyanide nwere ọtụtụ mineral ọla kọpa, n'ozuzu, a chọrọ 2.3 ruo 3.4 grams nke cyanide iji gbarie gram ọla kọpa.

(3) Ọ bụrụ na ọla edo mbụ ahụ nwere sphalerite ma ọ bụ smithsonite, ha ga-ejikwa sodium cyanide meghachi omume iji mepụta zinc cyanide na carbonates. Mmeghachi omume ndị a bụ:

• [ZnS+4NaCN→Na2[Zn(CN)4]+Na2S]

• [ ZnCO3+4NaCN→Na2Zn(CN)4+Na2CO3]

(4) Ọ bụrụ na ọla edo nwere arsenopyrite, mercury, selenium, tellurium, wdg, ha ga-emeghachi omume na sodium cyanide. Mgbe ahụ ore nwere nkume carbonaceous, karịsịa ndị bara ụba na carbon organic, adsorption nke cyanide na-esiwanye ike, na-eme ka cyanide leaching nke ọla edo sie ike karị.

3. Hydrolysis nke Cyanides

Na ngwọta, cyanides na-enweta ogo dị iche iche nke hydrolysis dabere na pH, yana ọnụọgụ cyanide hydrogen emepụtara na-emetụta alkalinity nke ngwọta. Enwere ike ịnọchite anya mmeghachi omume dị ka ndị a:

• [NaCN + H2O → NaOH + HCN↑]

• [CN⁻ + 2H2O → HCOO⁻ + NH3]

Mgbe hydrolysis gasịrị, akụkụ nke cyanide na-emepụta hydrogen cyanide, ebe akụkụ ọzọ na-eme ka oxidatively hydrolyzed, jiri nwayọọ nwayọọ na-emepụta formic acid na amonia. Na 100°C, CN⁻ na-atụfu 50%, na 130°C, ọ na-atụfu 85%.

N'ime usoro cyanidation maka igwu ọla edo, hydrogen cyanide bụ gas na-egbu egbu nke ukwuu. Ọ bụrụ na ejighị ya nke ọma, ọ nwere ike ibute ịba ụba nke NaCN, na-ebuli ọnụ ahịa mmepụta ihe, na ịkpata mmetọ gburugburu ebe obibi, yana itinye ihe ize ndụ ahụike nye ndị ọrụ. Ọnụ ego nke HCN mepụtara dịgasị iche na pH nke ngwọta: na pH 10.5. naanị 6.1% nke hydrogen cyanide na-emepụta; na pH 10. ọ na-abawanye ruo 17%; na pH 9.5. ọ ruru 39.2%; na pH 9.0. bụ 67.1%. Ya mere, na osisi CIP gold (Carbon-in-Pulp), a na-edozi pH n'etiti 11 na 12 iji chịkwaa hydrolysis nke cyanides.

4. The oxidation nke cyanide (CN-) site etisasịwo oxygen (O2)

Iji welie mgbasa nke ọla edo, ma CN- na O2 ga-etinyerịrị aka na mmeghachi omume ahụ. N'ime ụlọ okpomọkụ na nrụgide, ihe kachasị solubility nke oxygen bụ 8.2 mg / L. Mgbakwunye nke onye na-ahụ maka oxidizing siri ike nwere ike ime ka ntinye nke oxygen na ngwọta ya dịkwuo elu, na-eme ka usoro nkwụsị ahụ dịkwuo ngwa ngwa. Otú ọ dị, ọnụ ọgụgụ nke oxygen na cyanide ga-edozirịrị; ma ọ bụghị ya, ọnụ ọgụgụ leaching nwere ike ibelata. oxygen gbazere na-emeghachi omume na cyanide iji mepụta cyanate, nke kwụsiri ike na ngwọta alkaline. Otú ọ dị, na pH dị ala karịa 7. ọ na-emepụta amonia na bicarbonate. Nha nhata mmeghachi omume bụ ndị a:

• [1/2 O2 + CN– → (CNO)–]

• [(CNO)– + 2 H2O → HCO3– + NH3]

Ya mere, mmeghachi omume a nwere ike iduga oriri cyanide n'oge usoro leaching ma ọ bụ electrolysis.

5. Adsorption nke Cyanide site na Clay

N'oge usoro cyanidation, ígwè sulfide na ore na-emepụta iron hydroxide, ebe silicates na ore na-emepụta colloidal silica na alkaline ọkara. Ihe abụọ ndị a nwere ikike nke ịgbasa cyanide, na-eduga na mfu nke cyanide yana ihe fọdụrụ na leaching.

6. Nri nke cyanide site na ihe ndị ọzọ

(1) Mgbe slurry na-akpali ma jupụta na ikuku, CO2 ga-adị na ngwọta. CO2 ga-emeghachi omume na cyanide.

• [2NaCN+CO2+H2O→Na2CO3+2HCN↑]

(2) Sulfide mineral dị ka pyrite na mbụ ore na-emeghachi omume na etisasịwo oxygen (O2) na ore pulp, na sulfites na sulfates pụta ga-emeghachi omume na cyanide.

• [FeS+2O2→FeSO4]

• [FeSO4+6NaCN→Na4Fe(CN)6+Na2SO4]

Enwere ike ịgbakwunye obere obere CaO ma ọ bụ Ca (OH) 2 tupu ịsa ahụ iji wepụ acid ahụ ma gbochie mmeghachi omume dị n'elu ime.

na ngwụcha

Ihe dị n'elu bụ akụkụ 6 nke oriri cyanide na usoro cyanidation ọla edo. Na mgbakwunye na cyanide achọrọ maka ịgbasa ọla edo nkịtị, enwere ọtụtụ oriri na-adịghị mkpa, dị ka anyị mmeghachi omume na mineral ndị ọzọ metụtara, onwe-hydrolysis, wdg. 

Ọ bụrụ na ị nwere ajụjụ ọ bụla gbasara ọdịnaya dị n'elu, ma ọ bụ chọọ ịma , ị nwere ike ịkpọtụrụ ndị ahịa n'ịntanetị ma ọ bụ nyefee ozi, anyị ga-akpọtụrụ gị ozugbo enwere ike!