Sodium Cyanide Electroplating Zinc Njira: Kusanthula Kwakukulu

Introduction

Electroplating ndi njira yomwe imagwiritsidwa ntchito kwambiri m'mafakitale osiyanasiyana kuti apititse patsogolo mawonekedwe azitsulo. Mwa njira zosiyanasiyana za electroplating, Sodium Cyanide electroplating zinc imakhala ndi udindo waukulu chifukwa cha mawonekedwe ake apadera komanso zabwino zake. Nkhaniyi ikufuna kupereka kusanthula kwatsatanetsatane kwa Sodium cyanide electroplating zinc ndondomeko, kuphimba mfundo zake, ndondomeko masitepe, kusamba zikuchokera, ndi maganizo ntchito.

Mfundo za Sodium Cyanide Electroplating Zinc

Mu sodium cyanide electroplating zinki ndondomeko, mfundo yaikulu zachokera electrolysis. Kusamba kwa electroplating kumakhala ndi ayoni a zinc ndi zigawo zina. Pamene mphamvu yamagetsi ikugwiritsidwa ntchito, ayoni a zinki mu bafa amachepetsedwa pa cathode (chinthu chomwe chiyenera kuikidwa), ndipo maatomu a zinki amaikidwa pamwamba pa cathode, kupanga zokutira za zinki. Kukhalapo kwa Sodium cyanide Kusamba kumagwira ntchito yofunika kwambiri. Zimagwira ntchito ngati zovuta, kupanga ma complex okhazikika okhala ndi ayoni a zinc. Kuphatikizika uku kumathandizira kuwongolera kuchuluka kwa zinc ndikuwongolera mtundu wa zinc wosanjikiza. Mwachitsanzo, zomwe zingachitike zitha kuyimiridwa mophweka ngati: Zn(CN)₄²⁻ + 2e⁻ → Zn + 4CN⁻ pa cathode. Ma ion a zinc opangidwa ndi mawonekedwe a Zn(CN)₄²⁻ amakhala okhazikika pakusamba, zomwe zimapangitsa kuti pakhale mawonekedwe ofananirako komanso owoneka bwino a zinc poyerekeza ndi machitidwe omwe sali ovuta.

Ndondomeko Zoyendetsera

1. Kukonzekera kwa gawo lapansi

Pamaso pa electroplating, gawo lapansi (chinthu chachitsulo chokutidwa) chiyenera kukonzedwa bwino. Gawo ili ndilofunika kuti zitsimikizidwe bwino za zokutira za zinki.

• Kusokonezeka: Choyambiracho chimachotsedwa mafuta kuti chichotse mafuta, mafuta, kapena zinthu zina zodetsa zomwe zili pamwamba pake. Izi zitha kuchitika kudzera m'njira monga kuchotsera mafuta a alkaline, komwe choyambiracho chimamizidwa mu yankho la alkaline lomwe lili ndi ma surfactants. Njira ya alkaline imagwira ntchito ndi mafutawo, ndikupangitsa kuti atsukidwe. Mwachitsanzo, njira yachizolowezi yochotsera mafuta a alkaline ingakhale ndi sodium hydroxide, sodium Carbonmankhwala ophera tizilombo toyambitsa matenda monga sodium dodecyl sulfate.

• Kusankha: Pambuyo pochotsa mafuta, pickling imachitika kuti ichotse dzimbiri, ma oxides, ndi zonyansa zina zapadziko lapansi. Njira ya asidi, monga hydrochloric acid kapena sulfuric acid, imagwiritsidwa ntchito potola. Asidi amachitira ndi oxides pamwamba, kuwasungunula iwo. Mwachitsanzo, pakakhala dzimbiri (iron oxide) pagawo lachitsulo, zomwe zimachitika ndi hydrochloric acid ndi: Fe₂O₃ + 6HCl → 2FeCl₃ + 3H₂O. Pambuyo pa pickling, gawo lapansi limatsukidwa bwino ndi madzi kuchotsa asidi otsala.

2. Kukonzekera kwa Bafa la Electroplating

Kukonzekera kwa kusamba kwa electroplating ndi sitepe yofunika kwambiri mu sodium cyanide electroplating zinc ndondomeko.

• zosakaniza: Zigawo zazikulu za kusamba zikuphatikizapo zinc oxide (ZnO) monga gwero la ayoni zinc, sodium cyanide (NaCN) monga complexing agent, ndi sodium hydroxide (NaOH) monga mchere conductive. Kuphatikiza apo, zowonjezera zina zitha kuphatikizidwa kuti zithandizire kuwongolera bwino, monga zowunikira. Pamalo osambira otsika - cyanide electroplating, mawonekedwe ake angakhale: ZnO 8 - 12 g/L, NaCN 10 - 20 g/L, NaOH 80 - 120 g/L.

• Kusakaniza Njira: Choyamba, gawo la madzi (pafupifupi gawo limodzi mwa magawo atatu a voliyumu yonse yosamba) amawonjezedwa ku thanki yopangira. Kenako, kuchuluka kofunikira kwa sodium cyanide ndi sodium hydroxide akuwonjezeredwa ndikugwedezeka mpaka kusungunuka kwathunthu. Kenako, zinc oxide imawonjezedwa pang'onopang'ono ku yankho ndikuyambitsa mosalekeza. Zinc oxide imakhudzidwa ndi sodium hydroxide ndi sodium cyanide kupanga zofunikira. Pambuyo pa kuwonjezera kwa zinc oxide, kusamba kumachepetsedwa ndi voliyumu yomwe mukufuna ndi madzi. Pomaliza, zowonjezerazo zimawonjezeredwa malinga ndi malangizo a wopanga.

3. Njira ya Electroplating

• Kukhazikitsa Electroplating Cell: Selo ya electroplating imakhala ndi kusamba kwamadzi, cathode (gawo laling'ono loti lipangidwe), ndi anode. Anode nthawi zambiri amapangidwa ndi zinc chitsulo. Mphamvu yamagetsi ikadutsa mu bafa, ma ion a zinki amasungunuka kuchokera ku anode kupita ku bafa ndikuyikidwa pa cathode. Kachulukidwe kakali pano, komwe ndi kuchuluka kwapano pagawo la gawo la cathode, kumayendetsedwa mosamala. Pa sodium cyanide electroplating zinc, kachulukidwe kameneka kamakhala koyambira 1 - 5 A/dm². Kuchepa kwa kachulukidwe kapano kungapangitse kuti kachulukidwe kachuluke pang'onopang'ono koma kungayambitse kuyanika kofananako komanso kowoneka bwino. Kumbali ina, kachulukidwe kakang'ono kamakono kumatha kukulitsa kuchuluka kwa matupiko koma kungayambitse zovuta monga kusanja kofananira ndi kuyaka kwa zokutira pamalo apamwamba.

• Kutentha ndi Kusokonezeka: Kutentha kwa kusamba kwa electroplating kumakhudzanso ndondomeko ya plating. Nthawi zambiri, kutentha kwa kusamba kumasungidwa mumtundu wa 20 - 40 ° C. Kutentha kwapamwamba kumatha kukulitsa kuchuluka kwa matupiko koma kumachepetsanso kufalikira kwa cathode, zomwe zimatsogolera ku zokutira zokulirapo. Kusokonezeka kwa kusamba ndikofunikira kuonetsetsa kufalitsa yunifolomu kwa ayoni kuzungulira cathode. Izi zitha kutheka kudzera mu chipwirikiti cha makina, monga kugwiritsa ntchito chipwirikiti, kapena kuphulika kwa mpweya. Kusokonezeka kumathandizira kubwezeretsanso ma ion a zinc pafupi ndi cathode pamwamba, kulepheretsa mapangidwe a ndende zomwe zingayambitse kusanja kofanana.

4. Post - mankhwala

• Kuyeretsa: Pambuyo pa electroplating, chinthu chophwanyika chimatsukidwa bwino ndi madzi kuchotsa njira yotsalira yotsalira pamwamba pake. Masitepe angapo otsuka amatha kuchitidwa, ndikutsuka koyamba kukhala m'madzi ozizira kuti muchotse kuchuluka kwa yankho, ndikutsatiridwa ndi ma rinses owonjezera m'madzi oyera kuti muwonetsetse kuchotsedwa kwathunthu kwa zoyipa zilizonse.

• Chromating: Chromating nthawi zambiri imachitidwa kuti ipititse patsogolo kukana kwa dzimbiri kwa zinc - plated layer. Chinthu chokutidwacho chimamizidwa mu njira ya chromating, yomwe imakhala ndi chromic acid kapena mchere wake. Njira yopangira chromating imapanga mawonekedwe owonda, oteteza chromate kutembenuka pamwamba pa zokutira zinki. Chosanjikizachi chimapereka chitetezo chowonjezereka ku dzimbiri pochita ngati chotchinga komanso ndi kudzichiritsa tokha kumlingo wina pamene pamwamba pakanda. Pali mitundu yosiyanasiyana ya chromating, monga yellow chromating, blue - white chromating, ndi black chromating, iliyonse ikupereka milingo yosiyana ya kukana dzimbiri ndi mawonekedwe okongola.

• Kusaka: Pomaliza, chinthu chokutidwa ndi chromated chimawuma. Pazigawo zing'onozing'ono, zikhoza kuumitsidwa mu chowumitsira centrifugal ndi mpweya wotentha, pamene zigawo zazikulu zingakhale mpweya - zouma kutentha. Kuyanika ndikofunikira kuti tipewe kupanga mawanga amadzi ndikuwonetsetsa kukhazikika kwanthawi yayitali kwa zokutira.

Maonekedwe a Bafa ndi Chikoka Chake

1. Zinc oxide (ZnO)

Zinc oxide ndiye gwero la ayoni a zinc mu bafa la electroplating. Kuchuluka kwa zinc oxide mu kusamba kumakhudza kuchuluka kwa nthaka. Kuchulukitsidwa kwa zinc oxide nthawi zambiri kumabweretsa kutsika kwakukulu. Komabe, ngati kuchuluka kwa ayoni ya zinki ndikwambiri, kumatha kuyambitsa zovuta monga kuponya kopanda mphamvu (kuthekera kwa plating yankho kuyika zokutira yunifolomu pazinthu zowoneka bwino) komanso zokutira zokulirapo. M'mabafa otsika a cyanide, chitsulo choyenera cha zinc oxide chimakhala chofanana ndi chomwe tanena kale (8 - 12 g/L), chomwe chimapangitsa kuti pakhale kusiyana pakati pa kuyika ndi mtundu wa zokutira.

2. Sodium Cyanide (NaCN)

Sodium cyanide imagwira ntchito ngati chothandizira pakusamba. Amapanga zinthu zokhala ndi ayoni a zinc, monga Zn(CN)₄²⁻. Kuchuluka kwa sodium cyanide kumakhudza kukhazikika kwa zovuta izi ndipo, chifukwa chake, kuyika kwa zinc. M'malo osambira a cyanide apamwamba, sodium cyanide yochulukirapo imagwiritsidwa ntchito, yomwe imapereka mphamvu zoponya bwino komanso zokutira zabwino kwambiri. Komabe, malo osambira okwera - cyanide amakhala pachiwopsezo chachikulu cha chilengedwe komanso chitetezo chifukwa cha kawopsedwe ka cyanide. Mosiyana, osambira otsika - cyanide, omwe amagwiritsidwa ntchito kwambiri masiku ano, amagwiritsa ntchito sodium cyanide yochepa (mwachitsanzo, 10 - 20 g/L). Malo osambirawa amaperekabe mphamvu zabwino zoponyera ndi zokutira pamene amachepetsa nkhawa za chilengedwe ndi chitetezo pamlingo wina. Chiŵerengero cha sodium cyanide ku zinc oxide (NaCN/ZnO chiŵerengero) chimagwiranso ntchito yofunika kwambiri. Chiŵerengero choyenera chimatsimikizira kupangidwa kwa ma complexes okhazikika komanso mikhalidwe yabwino yopangira. Mwachitsanzo, m'mapulogalamu ena, chiŵerengero cha NaCN/ZnO cha 1.5 - 2.5 chimakondedwa.

3. Sodium Hydrooxide (NaOH)

Sodium hydroxide imagwira ntchito ngati mchere wochititsa chidwi mu kusamba, ndikuwonjezera mphamvu yamagetsi ya yankho. Izi zimathandiza kuti kusamutsidwa kothandiza kwambiri kwapano panthawi ya electroplating. Zimathandizanso kusunga pH ya bafa. PH ya sodium cyanide electroplating zinc bath nthawi zambiri imakhala mu alkaline range, mozungulira pH 12 - 14. pH yokhazikika ndiyofunikira kuti ma complexes azikhala okhazikika komanso ndondomeko yonse yopangira. Ngati pH ili yotsika kwambiri, ma complexes amatha kuwola, zomwe zimapangitsa kuti pakhale zotsatira zoyipa. Kumbali ina, ngati pH ndi yokwera kwambiri, imatha kuyambitsa mavuto monga kudziwira kwambiri kwa anode komanso kupanga zinc hydroxide kumadzimadzi.

4. Zowonjezera

• Zowunikira: Zowunikira zimawonjezedwa posamba kuti ziwongolere kuwala ndi kuwala kwa zokutira zinki. Amagwira ntchito posintha mawonekedwe a pamwamba pa nthaka yosanjikiza ya zinki pamlingo wa atomiki. Mankhwala achilengedwe monga saccharin, coumarin, ndi mchere wina wa quaternary ammonium amagwiritsidwa ntchito ngati zowunikira. Mwachitsanzo, saccharin imatha kukopa pamwamba pa cathode panthawi ya electroplating, kulepheretsa kukula kwa makristasi a zinki m'njira zina ndikulimbikitsa mapangidwe a malo osalala komanso owala.

• Otsatsa: Ma leveler amathandiza kusalaza zolakwika zilizonse pagawo laling'ono panthawi ya electroplating. Amakonda kusungitsa madera apamwamba - apano - osasunthika a gawo lapansi, kuchepetsa kusiyana kwa makulidwe pakati pa madera okwera - ndi otsika - apano - ndikupangitsa kuti pakhale zokutira zofananira. Ma polima ena ndi ma surfactants amatha kugwira ntchito ngati ma leveler mu bafa la electroplating.

• Antioxidants ndi Stabilizers: Zowonjezerazi zimagwiritsidwa ntchito poletsa makutidwe ndi okosijeni a zigawo zikuluzikulu mu kusamba, makamaka ayoni a cyanide. Cyanide ikhoza kukhala oxidized pamaso pa mpweya ndi zonyansa zina, zomwe zingayambitse kuchepa kwa mphamvu ya complexing wothandizira ndi kusintha kwa madzi osamba. Antioxidants monga sodium sulfite akhoza kuwonjezeredwa ku kusamba kuti scavenge mpweya ndi kuteteza makutidwe ndi okosijeni wa cyanide. Ma Stabilizers amawonjezedwanso kuti asunge bata la kusamba pakapita nthawi, kuwonetsetsa kuti plating ikhale yogwirizana.

Zogwira Ntchito

1. Njira Zodzitetezera

Popeza sodium cyanide ndi poyizoni kwambiri, kusamala mosamalitsa chitetezo kuyenera kutengedwa panthawi yosamalira ndikugwiritsa ntchito njira ya electroplating. Onse ogwira nawo ntchito ayenera kuvala zida zoyenera zodzitetezera, kuphatikiza magolovesi, magalasi, ndi zopumira. Malo opangira ma electroplating ayenera kukhala ndi mpweya wabwino kuti apewe kudzikundikira kwa utsi wapoizoni. Pakatayika kapena ngozi iliyonse yokhudzana ndi sodium cyanide, njira zoyankhira mwadzidzidzi ziyenera kutsatiridwa. Izi zingaphatikizepo kusokoneza cyanide ndi mankhwala oyenerera (monga ma hypochlorite solutions) ndikudziwitsa akuluakulu a chitetezo.

2. Kusamalira Bafa

• Kusanthula Kwanthawi Zonse: Mapangidwe a kusamba kwa electroplating kuyenera kufufuzidwa nthawi zonse kuti zitsimikizidwe kuti kuchuluka kwa zinc oxide, sodium cyanide, sodium hydroxide, ndi zowonjezera zili mumtundu woyenera. Njira zowunikira monga titration zitha kugwiritsidwa ntchito kudziwa kuchuluka kwa zigawozi. Mwachitsanzo, ndende ya ayoni zinki angadziwike ndi titrating chitsanzo cha kusamba ndi muyezo EDTA (ethylenediaminetetraacetic acid) njira.

• Kuwongolera Kuwononga: Kuyipitsidwa kwa kusamba kumatha kuchitika kuchokera kuzinthu zosiyanasiyana, monga zonyansa muzopangira, 带入 zazinthu zakunja kuchokera ku gawo lapansi panthawi yopaka, komanso kukulitsa zomwe zimachitika ndi - mankhwala. Kuletsa kuipitsidwa, kusefera koyenera kwa kusamba kuyenera kuchitika. Makina osefa okhala ndi zosefera zoyenera amatha kuchotsa tinthu tating'onoting'ono ndi zinthu zina zowononga organic. Komanso, nthawi ndi nthawi kuyeretsa kusamba kungakhale kofunikira. Mwachitsanzo, ngati zonyansa za heavy metal (monga mkuwa kapena mtovu) zaunjikana m’bafa, zimatha kuchotsedwa powonjezera mankhwala omwe amapanga madzi ndi zonyansazi, kenako kusefera.

• Kuwonjezeredwa kwa Zigawo: Pamene njira ya electroplating ikupitirira, zigawo zomwe zili mu bafa zimadyedwa. Zinc imayikidwa pa cathode, ndipo zina mwazinthu zovuta komanso zowonjezera zimatha kuwola kapena kudyedwa m'mbali. Chifukwa chake, kuwonjezeredwa pafupipafupi kwa zinc oxide, sodium cyanide, sodium hydroxide, ndi zowonjezera zimafunikira kuti muzitha kusamba. Mlingo wa kubwezeretsanso ukhoza kutsimikiziridwa kutengera nthawi yopukutira, kuchuluka kwa magawo omwe amakutidwa, ndi zotsatira za kusanthula kwa bafa.

3. Mavuto

• Osauka Coating Adhesion: Ngati zokutira za zinki zili ndi kusamata bwino kwa gawo lapansi, zomwe zingayambitse zimaphatikizapo kusamalidwa bwino kwa gawo lapansi, mawonekedwe osamba osayenera (monga pH yolakwika kapena kutsika kwa agent), kapena kuchuluka kwa kuipitsidwa mubafa. Kuti athetse vutoli, njira yochiritsira ikuyenera kuwunikiridwa ndikuwongoleredwa. Masamba osambirawo ayenera kufufuzidwa ndi kusinthidwa ngati kuli kofunikira, ndipo njira ziyenera kuchitidwa kuti muchepetse kuipitsidwa.

• Kupaka Mosiyana: Kuyika kosagwirizana kumatha kuyambitsidwa ndi zinthu monga kugawa kosayenera kwapano mu cell ya electroplating, kusakhazikika kofanana kwa bafa, kapena kusiyanasiyana kwa geometry ya gawo lapansi. Kuti athetse vutoli, kukhazikitsidwa kwa selo la electroplating kungasinthidwe kuti zitsimikizire kugawa kwamakono kofananira. Njira yosokoneza imatha kukonzedwa bwino, ndipo zomangira zimatha kupangidwa kuti zizigwira gawo lapansi m'njira yomwe imalimbikitsa kuyika kwa yunifolomu. Kwa magawo owoneka bwino, njira zapadera zopangira ma plating kapena kugwiritsa ntchito ma anode othandizira angafunike.

• Kupaka kosalala kapena kwakuda: Kupaka kwa zinki kosawoneka bwino kapena kwakuda kumatha kukhala chifukwa cha kusakwanira kwa zowunikira mu bafa, kuchuluka kwa zonyansa, kapena zopangira zolakwika (monga kusachulukira kwakukulu kwakanthawi kapena kutentha kwa bafa). Kuphatikizika kowala kuyenera kufufuzidwa ndikusinthidwa ngati kuli kofunikira. Kusamba kuyenera kuyeretsedwa kuti kuchotse zonyansa, ndipo magawo opaka akuyenera kukonzedwa bwino.

Kutsiliza

Njira ya sodium cyanide electroplating zinc ndi njira yogwiritsidwa ntchito kwambiri komanso yofunikira popereka kukana kwa dzimbiri ndi kumaliza kukongoletsa kuzinthu zachitsulo. Kumvetsetsa mfundo zake, masitepe, kapangidwe ka malo osambira, ndi momwe amagwiritsidwira ntchito ndikofunikira kuti tipeze zotsatira zapamwamba kwambiri. Ngakhale kuti ili ndi zovuta zachilengedwe ndi chitetezo chokhudzana ndi kugwiritsa ntchito sodium cyanide, ndi njira zoyenera zotetezera komanso kupititsa patsogolo njira zowonjezera zachilengedwe (monga njira zochepetsera - cyanide kapena cyanide - free), ikupitiriza kugwira ntchito yaikulu m'mafakitale osiyanasiyana, kuphatikizapo magalimoto, ndege, ndi zamagetsi. Poyang'anira mosamala mbali zonse za ndondomekoyi, opanga amatha kupanga zinki - zodzaza ndi zinthu zabwino kwambiri komanso ntchito.