Sodium Cyanide Consumption hauv Kub Extraction piav qhia

Nyob rau hauv cov txheej txheem ntawm extracting kub los ntawm cyanide tebchaw, Sodium cyanide yog noj nyob rau hauv ntau txoj kev. Sodium cyanide yog feem ntau siv leaching tus neeg sawv cev Hauv kev rho tawm kub, thiab theoretically, tsuas yog 0.5 grams ntawm Sodium Cyanide yuav tsum tau leaching 1 gram ntawm kub. Txawm li cas los xij, nyob rau hauv feem ntau kub cyanidation nroj tsuag, qhov tseeb noj ntawm cyanide yog ho ntau dua, feem ntau tshaj theoretical xam los ntawm 50 mus rau 100 zaug.

Cov yam tseem ceeb uas ua rau muaj kev noj ntau ntawm cyanide hauv lub kub cyanidation txheej txheem muaj xws li:

1. Kev siv Cyanide hauv cov txheej txheem kub dissolution

Cyanide nroj tsuag tau siv sodium cyanide kom yaj kub los ntawm ore thiaj li yuav rov qab kub los ntawm cov leachate. Cov tshuaj lom neeg muaj feem cuam tshuam yog raws li hauv qab no:

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

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

Los ntawm cov tshuaj tiv thaiv electrochemical, nws tau paub tias kev sib cais 1 gram ntawm kub yuav tsum tau noj 0.92 grams ntawm sodium cyanide.

2. Kev siv Cyanide hauv kev cuam tshuam nrog Associated Base Metals

(1) Qee cov pob zeb kub muaj cov khoom siv xws li pyrite, magnetite, chalcopyrite, sulfate minerals, hydroxides, thiab oxides. Thaum lub sij hawm crushing theem, hlau hmoov yog generated, uas maj mam reacts nrog sodium cyanide, nce siv cyanide. Cov tshuaj tiv thaiv yog raws li nram no:

• [FeS2+NaCN → FeS+NaCNS]

• [Fe(OH)2+2NaCN → Fe(CN)2+2NaOH]

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

• [S+NaCN →NaCNS]

(2) Yog hais tias cov ore kub muaj ntau hom tooj liab minerals, lawv kuj yuav hnov ​​​​mob nrog sodium cyanide los ua tooj liab cyanide complexes, noj cyanide hauv cov txheej txheem. Cov tshuaj tiv thaiv yog raws li nram no:

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

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

Vim muaj zog reactivity ntawm sodium cyanide nrog ntau tooj liab minerals, feem ntau, 2.3 mus rau 3.4 grams ntawm cyanide yuav tsum tau yaj 1 gram ntawm tooj liab.

(3) Yog hais tias tus thawj kub ore muaj sphalerite los yog smithsonite, lawv kuj yuav hnov ​​mob nrog sodium cyanide los ua zinc cyanide thiab carbonates. Cov tshuaj tiv thaiv yog raws li nram no:

• [ZnS+4NaCN → Na2[Zn(CN)4]+Na2S]

• [ ZnCO3+4NaCN→Na2Zn(CN)4+Na2CO3]

(4) Yog hais tias cov ore kub muaj arsenopyrite, mercury, selenium, tellurium, thiab lwm yam, lawv kuj yuav hnov ​​​​mob nrog sodium cyanide. Thaum lub cev ore muaj carbonaceous pob zeb, tshwj xeeb tshaj yog cov nplua nuj nyob rau hauv cov organic carbon, cov adsorption ntawm cyanide yuav muaj zog, ua rau cov cyanide leaching ntawm kub nyuaj.

3. Hydrolysis ntawm Cyanides

Hauv kev daws teeb meem, cyanides undergo ntau qib ntawm hydrolysis nyob ntawm pH, nrog rau tus nqi ntawm hydrogen cyanide tsim muaj feem xyuam rau alkalinity ntawm cov tshuaj. Cov tshuaj tiv thaiv tuaj yeem sawv cev raws li hauv qab no:

• [NaCN + H2O → NaOH + HCN↑]

• [CN⁻ + 2H2O → HCOO⁻ + NH3]

Tom qab hydrolysis, ib feem ntawm cov cyanide tsim hydrogen cyanide, thaum lwm feem yog oxidatively hydrolyzed, maj mam tsim formic acid thiab ammonia. Ntawm 100 ° C, CN⁻ poob 50%, thiab ntawm 130 ° C, nws poob 85%.

Nyob rau hauv cov txheej txheem cyanidation rau cov mining kub, hydrogen cyanide yog cov pa phem heev. Yog tias tsis muaj kev tswj hwm zoo, nws tuaj yeem ua rau muaj kev siv NaCN ntau ntxiv, nce nqi tsim khoom, thiab ua rau muaj kuab paug ib puag ncig, nrog rau ua rau muaj kev phom sij rau cov neeg ua haujlwm. Tus nqi ntawm HCN tsim tawm txawv nrog pH ntawm cov tshuaj: ntawm pH 10.5. tsuas yog 6.1% ntawm hydrogen cyanide yog tsim; ntawm pH 10. nws nce mus rau 17%; pH ntawm 9.5. nws nce mus txog 39.2%; thiab pH 9.0. nws yog 67.1%. Yog li ntawd, hauv kub CIP (Carbon-in-Pulp) cov nroj tsuag, pH feem ntau yog hloov mus rau ntawm 11 thiab 12 los tswj cov hydrolysis ntawm cyanide.

4. Lub oxidation ntawm cyanide (CN-) los ntawm yaj oxygen (O2)

Txhawm rau txhim kho qhov tawg ntawm kub, ob qho tib si CN- thiab O2 yuav tsum koom nrog cov tshuaj tiv thaiv. Nyob rau hauv chav tsev kub thiab siab, qhov siab tshaj plaws solubility ntawm oxygen yog 8.2 mg / L. Qhov sib ntxiv ntawm tus neeg sawv cev oxidizing muaj zog tuaj yeem ua rau kom cov pa oxygen ntau ntxiv hauv cov tshuaj, ua kom cov txheej txheem leaching sai. Txawm li cas los xij, qhov piv ntawm oxygen rau cyanide yuav tsum sib npaug; txwv tsis pub, qhov leaching tus nqi yuav txo. Dissolved oxygen reacts nrog cyanide los tsim cyanate, uas yog ruaj khov nyob rau hauv alkaline daws. Txawm li cas los xij, ntawm pH qis dua 7. nws hydrolyzes tsim ammonia thiab bicarbonate. Cov kev sib npaug sib npaug yog raws li nram no:

• [1/2 O2 + CN– → (CNO)–]

• [(CNO)– + 2 H2O → HCO3– + NH3]

Yog li, qhov tshuaj tiv thaiv no tuaj yeem ua rau kev noj ntawm cyanide thaum lub sij hawm leaching lossis electrolysis txheej txheem.

5. Adsorption ntawm Cyanide los ntawm av nplaum

Thaum lub sij hawm cyanidation txheej txheem, cov hlau sulfide nyob rau hauv lub ore generates hlau hydroxide, thaum lub silicates nyob rau hauv lub ore form colloidal silica nyob rau hauv ib tug alkaline nruab nrab. Ob leeg ntawm cov tshuaj no muaj ib lub peev xwm los adsorb cyanide, ua rau poob ntawm cyanide nrog rau cov leaching residue.

6. Kev siv cyanide los ntawm lwm yam tshuaj

(1) Thaum cov slurry yog nplawm thiab ntim nrog cua, CO2 yuav muaj nyob rau hauv cov tshuaj. CO2 kuj yuav hnov ​​​​mob nrog cyanide.

• [2NaCN+CO2+H2O→Na2CO3+2HCN↑]

(2) Sulfide minerals xws li pyrite nyob rau hauv thawj ore teb nrog yaj oxygen (O2) nyob rau hauv lub ore pulp, thiab cov resulting sulfites thiab sulfates kuj react nrog cyanide.

• [FeS + 2O2 → FeSO4]

• [FeSO4+6NaCN→Na4Fe(CN)6+Na2SO4]

Ib qho me me ntawm CaO lossis Ca (OH) 2 tuaj yeem ntxiv ua ntej leaching kom tsis txhob muaj cov kua qaub thiab tiv thaiv cov tshuaj tiv thaiv saum toj no tsis tshwm sim.

nyob rau hauv xaus

Cov saum toj no yog 6 yam ntawm kev siv cyanide hauv cov txheej txheem kub cyanidation. Ntxiv nrog rau cov cyanide uas yuav tsum tau ua rau lub cev qhuav dej ntawm cov kub, muaj ntau yam tsis tseem ceeb noj, xws li peb cov tshuaj tiv thaiv nrog lwm cov minerals cuam tshuam, self-hydrolysis, thiab lwm yam. 

Yog tias koj muaj lus nug txog cov ntsiab lus saum toj no, lossis xav paub txog, koj tuaj yeem sab laj kev pabcuam hauv online lossis xa lus, peb yuav tiv tauj koj sai li sai tau!