Amfanin Sodium Cyanide a cikin Haɗin Zinare An Bayyana

A yayin da ake cire zinare daga mahaɗan cyanide, ana shan sodium cyanide ta hanyoyi da dama. Sodium cyanide shine maganin cire zinare da aka fi amfani da shi a cikin cire zinare, kuma a ka'ida, ana buƙatar gram 0.5 na Sodium Cyanide don cire gram 1 na zinare. Duk da haka, a yawancin tsire-tsire na cyanide na zinare, ainihin yawan cyanide ya fi yawa, sau da yawa ya wuce lissafin ka'ida sau 50 zuwa 100.

Manyan abubuwan da ke haifar da yawan shan cyanide a cikin tsarin cyanidation na zinare sun haɗa da:

1. Amfani da Cyanide a cikin Tsarin Rushe Zinare

Masana'antar Cyanide suna amfani da sodium cyanide don narkar da zinare daga ma'adinai domin dawo da zinare daga ma'adinan. Halayen sinadarai da ke tattare da hakan sune kamar haka:

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

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

Daga halayen electrochemical, an san cewa narkar da gram 1 na zinariya yana buƙatar amfani da 0.92 grams na sodium cyanide.

2. Yin amfani da Cyanide a cikin Haɗin kai tare da Ƙarfa na Ƙarƙashin Ƙarfafawa

(1) Wasu ma'adanai na zinariya suna ɗauke da ma'adanai masu alaƙa kamar pyrite, magnetite, chalcopyrite, sulfate minerals, hydroxides, da oxides. A lokacin niƙa, ana samar da foda na ƙarfe, wanda ke amsawa a hankali tare da sodium cyanide, yana ƙara yawan shan cyanide . Halayen sune kamar haka:

• [FES2+NaCN→FeS+NaCNS]

• [Fe(OH)2+2NaCN→Fe(CN)2+2NaOH]

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

• [S+NaCN→NaCNS]

(2) Idan ma'adinan zinare ya ƙunshi nau'ikan ma'adanai na tagulla daban-daban, za su kuma yi da sodium cyanide don samar da rukunin cyanide na jan karfe, suna cinye cyanide a cikin tsari. Abubuwan da suka faru sune kamar haka:

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

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

Saboda karfi reactivity na sodium cyanide tare da yawa jan karfe ma'adanai, kullum, 2.3 zuwa 3.4 grams na cyanide ake bukata don narkar da 1 gram na jan karfe.

(3) Idan asalin gwal ɗin ya ƙunshi sphalerite ko smithsonite, za su kuma amsa da sodium cyanide don samar da zinc cyanide da carbonates. Abubuwan da suka faru sune kamar haka:

• [ZnS+4NaCN→Na2[Zn(CN)4]+Na2S]

• [ ZnCO3+4NaCN→Na2Zn(CN)4+Na2CO3]

(4) Idan ma'adinan zinare ya ƙunshi arsenopyrite, mercury, selenium, tellurium, da dai sauransu, za su kuma mayar da martani da sodium cyanide. Lokacin da jikin tama ya ƙunshi duwatsun carbonaceous, musamman waɗanda ke da wadataccen carbon carbon, adsorption na cyanide ya zama mai ƙarfi, yana sa ƙwayar cyanide na zinare ya fi wahala.

3. Hydrolysis na Cyanide

A cikin maganin, cyanides suna fuskantar matakai daban-daban na hydrolysis dangane da pH, tare da adadin hydrogen cyanide da aka samar yana da alaƙa da alkalinity na maganin. Ana iya wakiltar martanin kamar haka:

• [NaCN + H2O → NaOH + HCN↑]

• [CN⁻ + 2H2O → HCOO⁻ + NH3]

Bayan hydrolysis, wani yanki na cyanide yana haifar da hydrogen cyanide, yayin da wani sashi kuma yana samar da ruwa mai oxidatively, a hankali yana samar da formic acid da ammonia. A 100°C, CN⁻ ya yi hasarar 50%, kuma a 130°C, ya rasa 85%.

A cikin tsarin cyanidation don hakar gwal, hydrogen cyanide gas ne mai guba sosai. Idan ba a kula da shi yadda ya kamata ba, hakan na iya haifar da karuwar amfani da NaCN, da kara tsadar kayayyaki, da haifar da gurbatar muhalli, tare da haifar da illa ga lafiya ga masu aiki. Adadin HCN da aka samar ya bambanta da pH na maganin: a pH 10.5. kawai 6.1% na hydrogen cyanide aka samar; a pH 10. yana ƙaruwa zuwa 17%; da pH 9.5. ya kai 39.2%; da pH 9.0. ya canza zuwa +67.1%. Sabili da haka, a cikin tsire-tsire na CIP (Carbon-in-Pulp), pH yawanci ana daidaita shi zuwa tsakanin 11 da 12 don sarrafa hydrolysis na cyanides.

4. A oxidation na cyanide (CN-) ta narkar da oxygen (O2)

Don haɓaka adadin narkar da gwal, duka CN- da O2 dole ne su shiga cikin aikin. A dakin da zafin jiki da matsa lamba, matsakaicin solubility na oxygen shine 8.2 mg / L. Bugu da ƙari na wakili mai ƙarfi mai ƙarfi zai iya ƙara yawan iskar oxygen a cikin maganin, yana hanzarta aiwatar da aikin leaching. Duk da haka, dole ne a daidaita rabon oxygen zuwa cyanide; in ba haka ba, yawan leaching na iya raguwa. Narkar da iskar oxygen yana amsawa tare da cyanide don samar da cyanate, wanda ya tsaya a cikin maganin alkaline. Duk da haka, a wani pH kasa da 7. shi hydrolyzes don samar da ammonia da bicarbonate. Matsalolin amsawa sune kamar haka:

• [1/2 O2 + CN– → (CNO)–]

• [(CNO) – + 2 H2O → HCO3 – + NH3]

Sabili da haka, wannan halayen na iya haifar da amfani da cyanide a lokacin leaching ko hanyoyin lantarki.

5. Adsorption na Cyanide ta Clay

A lokacin aikin cyanidation, baƙin ƙarfe sulfide a cikin tama yana haifar da baƙin ƙarfe hydroxide, yayin da silicates a cikin tama suna samar da silica colloidal a cikin matsakaici na alkaline. Duk waɗannan abubuwa biyu suna da takamaiman ƙarfin da za su iya haɓaka cyanide, wanda ke haifar da asarar cyanide tare da ragowar leaching.

6. Amfani da cyanide ta wasu abubuwa

(1) Lokacin da slurry ya motsa kuma ya cika da iska, CO2 zai kasance a cikin maganin. CO2 kuma za ta mayar da martani da cyanide.

• [2NaCN+CO2+H2O→Na2CO3+2HCN↑]

(2) Ma'adinan Sulfide kamar pyrite a cikin ma'adanin asali suna amsawa tare da narkar da iskar oxygen (O2) a cikin ƙwayar tama, kuma sakamakon sulfites da sulfates za su yi amsa tare da cyanide.

• [FeS+2O2→FeSO4]

• [FeSO4+6NaCN→Na4Fe(CN)6+Na2SO4]

Ana iya ƙara ƙaramin adadin CaO ko Ca (OH) 2 kafin yin leaching don kawar da acid kuma hana abin da ke sama daga faruwa.

a ƙarshe

Abubuwan da ke sama sune abubuwan 6 na amfani da cyanide a cikin tsarin aikin cyanidation na zinariya. Baya ga cyanide da ake buƙata don narkar da zinari na al'ada, akwai yawancin abubuwan amfani da ba su da mahimmanci, irin mu mu amsa tare da sauran ma'adanai masu alaƙa, kai-hydrolysis, da dai sauransu. 

Idan kuna da wasu tambayoyi game da abubuwan da ke sama, ko kuna son sanin , kuna iya tuntuɓar sabis na abokin ciniki na kan layi ko aika saƙo, za mu tuntuɓe ku da wuri-wuri!