Kev ua haujlwm ntawm tus neeg sawv cev leaching sodium cyanide

1. Introduction

Sodium cyanide (NaCN) yog ib qho tseem ceeb heev rau kev rho tawm cov hlau muaj nqis, tshwj xeeb tshaj yog kub thiab nyiaj. Nws daim ntawv thov hauv kev lag luam mining pib txij li thaum xyoo pua 19th, thiab txij li thaum ntawd los nws tau dhau los ua ib feem tseem ceeb ntawm cov txheej txheem hydrometallurgical rau kev rov qab tau cov hlau muaj nqis no los ntawm lawv cov ores. Tsab xov xwm no delves rau hauv cov txheej txheem ntxaws ntxaws ntawm Sodium cyanide ua haujlwm li cas hauv cov txheej txheem Leaching , qhia txog nws cov tshuaj lom neeg, lub luag haujlwm ntawm ntau yam, thiab nws qhov tseem ceeb hauv kev rho tawm cov hlau muaj nqis.

2. Cov Khoom Siv Tshuaj Sodium Cyanide

Sodium cyanide yog ib yam khoom dawb, crystalline uas yaj tau yooj yim hauv dej. Hauv cov kua dej, nws tawg ua sodium ions (Na+) thiab Cyanide ions (CN-). Cyanide ion yog cov khoom tseem ceeb uas ua rau cov hlau muaj nqis tawm. Ua ib qho ligand muaj zog, nws muaj kev sib raug zoo rau qee cov hlau ions, tshwj xeeb tshaj yog kub thiab nyiaj. Cov yam ntxwv no tso cai rau nws los tsim cov khoom sib xyaw ruaj khov nrog cov hlau no, uas yog qhov tseem ceeb rau nws lub luag haujlwm ua tus neeg sawv cev tawm.

3. Cov txheej txheem Leaching kub thiab nyiaj nrog Sodium Cyanide

3.1 Tshuaj Reactions

Thaum siv Sodium Cyanide los ntxuav kub , qhov kev cuam tshuam tshwm sim thaum muaj oxygen nyob rau hauv ib puag ncig dej. Cov ions Cyanide tsim cov tshuaj sib xyaw ua ke nrog kub, nrog rau oxygen ua haujlwm ua tus neeg sawv cev oxidizing los pab txhawb cov txheej txheem. Ib qho kev cuam tshuam zoo sib xws tshwm sim thaum ntxuav nyiaj, qhov twg cov nyiaj atoms cuam tshuam nrog sodium cyanide thiab oxygen los tsim cov tshuaj sib xyaw ua ke ntawm cov nyiaj-cyanide uas yaj tau.

3.2 Cov Kauj Ruam Tawm Tsam ntawm Qib Molecular

Kev Sib Kis : Sodium cyanide sib cais hauv dej kom tso cov cyanide ions. Cov cyanide ions no, nrog rau cov pa oxygen uas yaj, txav mus los ntawm cov tshuaj kom mus txog saum npoo ntawm cov kub lossis nyiaj hauv cov hlau. Qhov ceev ntawm qhov kev sib kis no tuaj yeem cuam tshuam los ntawm cov yam xws li kub, kev sib xyaw, thiab viscosity ntawm cov tshuaj. Qhov kub siab dua thiab kev sib xyaw muaj zog dua feem ntau ua rau qhov nrawm ntawm kev sib kis los ntawm kev nce lub zog kinetic molecular thiab txhim kho kev sib tov cov tshuaj.

Kev Nqus Tau : Thaum nyob rau ntawm qhov chaw ntawm cov hlau, cov cyanide ions thiab cov pa oxygen molecules txuas lawv tus kheej rau ntawm qhov chaw ntawm cov kub lossis nyiaj me me. Kev nqus tau ntawm cyanide ions yog qhov xaiv heev vim lawv muaj zog sib raug zoo rau cov hlau. Kev nqus tau oxygen kuj tseem ceeb ib yam li nws muab lub zog oxidizing tsim nyog rau qhov kev cuam tshuam tom ntej.

Kev Tshuaj Xyuas Hluav Taws Xob : Ntawm ciam teb ntawm cov hlau thiab cov kua, kev tshuaj xyuas hluav taws xob tshwm sim. Cov kub lossis nyiaj atoms ntawm qhov chaw raug oxidized, hloov mus ua cov hlau ions. Cov hlau ions no tom qab ntawd ua rau cov adsorbed cyanide ions los tsim cov hlau-cyanide complexes uas yaj tau. Kev oxidation ntawm cov hlau tso tawm cov electrons, uas raug noj thaum lub sijhawm txo qis ntawm oxygen hauv cov kua.

Kev Tso Tawm thiab Kev Nthuav Tawm : Cov hlau-cyanide complexes uas tau tsim tawm yuav tawm ntawm qhov chaw ntawm cov hlau thiab tawg mus rau hauv lub cev tseem ceeb ntawm cov tshuaj. Qhov no ua rau txoj hauv kev rau cov cyanide ions tshiab thiab cov pa oxygen molecules kom nqus tau rau ntawm qhov chaw ntawm cov hlau, ua rau cov txheej txheem leaching txuas ntxiv mus.

4. Cov yam ntxwv cuam tshuam rau Leaching Efficiency ntawm Sodium Cyanide

4.1 Concentration ntawm Sodium Cyanide

Tus nqi ntawm sodium cyanide hauv cov tshuaj leaching zoo heev cuam tshuam tus nqi leaching. Thaum pib, raws li qhov concentration ntawm sodium cyanide nce, yog li tus nqi ntawm cov kub thiab nyiaj yog leached, vim ntau cyanide ions muaj nyob rau hauv cov hlau. Tab sis dhau ntawm ib qho taw tes, qhov leaching tus nqi yuav nres nce lossis txawm poob. Qhov no tuaj yeem tshwm sim vim tias nyob rau ntawm qhov siab siab, cyanide ions hnov ​​​​mob nrog dej los tsim hydrogen cyanide, cov tshuaj tsis haum tshuaj uas khiav tawm ntawm cov tshuaj, txo cov concentration ntawm cyanide ions rau leaching.

4.2 Concentration ntawm Oxygen

Oxygen yog qhov tseem ceeb hauv cov txheej txheem sodium cyanide leaching. Nws yuav tsum tau oxidize kub thiab nyiaj, ib kauj ruam tsim nyog ua ntej lawv yuav tsim complexes nrog cyanide ions. Cov qib siab ntawm cov pa oxygen yaj hauv cov tshuaj feem ntau ua rau kom nrawm nrawm dua. Txij li cov pa oxygen tau txwv tsis pub solubility hauv dej, cov txheej txheem leaching muaj feem ntau siv txoj hauv kev xws li aeration lossis oxygen-enriched cua los txhawb cov pa oxygen.

4.3 pH ntawm kev daws

Lub pH ntawm cov tshuaj leaching yog qhov tseem ceeb rau kev tswj xyuas qhov ruaj khov ntawm cyanide ions thiab tag nrho cov txheej txheem leaching. Cyanide ions nyob ruaj khov hauv cov tshuaj alkaline. Nyob rau hauv acidic tej yam kev mob, lawv hnov ​​​​mob nrog hydrogen ions los tsim cov tshuaj lom thiab tsis haum tshuaj hydrogen cyanide gas. Txhawm rau zam qhov no thiab ua kom muaj kev ruaj ntseg ntawm cyanide ions, pH ntawm cov tshuaj leaching feem ntau yog khaws cia ntawm 10 thiab 11. Txiv qaub feem ntau ntxiv rau cov tshuaj los kho thiab tswj cov pH ntawm qib zoo.

4.4 Ntsuas Kub

Qhov kub thiab txias cuam tshuam cov txheej txheem leaching hauv ntau txoj hauv kev. Feem ntau, qhov kub thiab txias ua rau muaj kev cuam tshuam tshuaj lom neeg, suav nrog kev nthuav tawm ntawm cov tshuaj reactants, adsorption ntawm cyanide ions thiab oxygen ntawm cov hlau nto, thiab cov tshuaj tiv thaiv electrochemical. Txawm li cas los xij, muaj qhov tsis zoo. Thaum kub siab, cyanide ions feem ntau yuav dhau mus rau hydrolysis, ua rau poob ntawm cyanide li hydrogen cyanide gas. Tsis tas li ntawd, qhov kub thiab txias tuaj yeem ua rau kom cov dej tsis huv hauv cov ore, uas tuaj yeem cuam tshuam cov txheej txheem leaching lossis ua rau ntau dhau ntawm cyanide ions. Hauv kev xyaum, qhov leaching kub feem ntau yog nyob ib ncig ntawm 20 - 30 ° C, txawm tias qhov kub siab dua yuav raug siv yog tias tsim nyog ntsuas los tswj cyanide hydrolysis.

4.5 Particle Size ntawm Ore

Qhov loj ntawm cov ore hais ncaj qha cuam tshuam rau leaching efficiency. Finer-grained ores muab thaj chaw loj dua rau cov tshuaj tiv thaiv ntawm cov hlau hais thiab cov tshuaj leaching. Qhov no txhawb kev nthuav dav sai ntawm cyanide ions thiab cov pa oxygen mus rau cov hlau nto thiab tsim cov hlau-cyanide complexes sai dua, uas ua rau muaj kev cuam tshuam ntau dua. Ntawm qhov tod tes, coarser-grained ores yuav xav tau lub sij hawm leaching ntev dua los yog ntau dua ua kom ua tiav tib theem ntawm cov hlau rov qab.

5. Qhov tseem ceeb ntawm kev nkag siab txog lub tshuab

Kev nkag siab li cas sodium cyanide ua haujlwm hauv cov txheej txheem leaching yog qhov tseem ceeb rau kev lag luam mining. Nws tso cai rau cov engineers thiab metallurgists kom zoo-tune leaching txheej txheem tsis, xws li reagent concentration, pH, kub, thiab particle loj, kom cov hlau rov qab. Los ntawm kev ua kom zoo rau cov xwm txheej no, kev lag luam tuaj yeem rho tawm cov hlau muaj txiaj ntsig zoo dua, txo cov reagent noj, thiab txo qhov cuam tshuam ib puag ncig ntawm kev siv sodium cyanide. Tsis tas li ntawd, qhov kev paub no tuaj yeem tsav kev txhim kho ntawm cov thev naus laus zis tshiab thiab muaj txiaj ntsig zoo dua, los ntawm kev txhim kho cov txheej txheem cyanide uas twb muaj lawm lossis tshawb nrhiav lwm cov leaching agents.

6. xaus

Sodium cyanide plays lub luag haujlwm tseem ceeb hauv kev rho tawm cov hlau muaj txiaj ntsig los ntawm cov txheej txheem leaching. Los ntawm kev nkag siab txog nws cov txheej txheem, nrog rau cov yam ntxwv uas cuam tshuam rau nws cov txiaj ntsig, kev lag luam mining tuaj yeem txuas ntxiv txhim kho nws cov haujlwm, ua rau kev rho tawm ntawm kub thiab nyiaj ntau dua thiab muaj txiaj ntsig. Kev tshawb fawb yav tom ntej yuav tsom mus rau kev ua kom zoo dua cov txheej txheem cyanide-based leaching los yog tsim cov kev hloov tshiab uas tuaj yeem txo cov kev pheej hmoo ntawm ib puag ncig cuam tshuam nrog kev siv sodium cyanide.