Corrosion inhibitors. Txoj kev tiv thaiv corrosion

2024 Tus sau: Howard Calhoun | [email protected]. Kawg hloov kho: 2023-12-17 10:28

Txhua xyoo, kwv yees li ib feem peb ntawm tag nrho cov hlau uas tsim nyob rau hauv lub ntiaj teb no tau ploj vim kev txhim kho thiab tshwm sim ntawm corrosion txheej txheem. Cov nqi cuam tshuam nrog kev kho thiab hloov cov khoom siv thiab kev sib txuas lus ntawm kev lag luam tshuaj feem ntau tshaj tus nqi ntawm cov ntaub ntawv xav tau rau lawv cov khoom siv los ntawm ob peb zaug. Corrosion yog hu ua spontaneous kev puas tsuaj ntawm cov hlau thiab ntau yam alloys nyob rau hauv kev cuam tshuam ntawm ib puag ncig. Txawm li cas los xij, koj tuaj yeem tiv thaiv koj tus kheej los ntawm cov txheej txheem no. Muaj ntau txoj hauv kev los tiv thaiv corrosion, nrog rau hom raug. Hauv kev lag luam tshuaj, feem ntau hom corrosion yog roj, atmospheric thiab electrochemical.

Tawm ntawm qhov xwm txheej

Kev xaiv ntawm txoj kev tawm tsam hauv qhov no tsis yog nyob ntawm tus yam ntxwv ntawm cov hlau nws tus kheej xwb, tab sis kuj nyob ntawm nws cov kev ua haujlwm. Cov txheej txheem ntawm kev tiv thaiv corrosion raug xaiv raws li qee yam, txawm li cas los xij, txawm tias ntawm no muaj ntau qhov teeb meem tshwm sim. Ib qho teeb meem tshwj xeeb yog txuam nrog kev xaiv ntawm ib qho kev xaiv rau ntau qhov chaw ib puag ncig nrogparameters uas hloov thaum lub sij hawm tus txheej txheem. Qhov no feem ntau tshwm sim hauv kev lag luam chemical. Corrosion tiv thaiv txoj kev siv nyob rau hauv kev xyaum yog muab faib raws li qhov xwm ntawm lawv cov kev cuam tshuam rau ib puag ncig thiab hlau.

Environmental impact

Txawm tias nyob rau Hnub Nyoog Nrab Hnub nyoog, cov tshuaj tshwj xeeb tau paub, uas tau nthuav tawm hauv cov khoom me me, uas ua rau nws muaj peev xwm txo tau qhov aggressiveness ntawm corrosive ib puag ncig. Rau cov hom phiaj no, nws yog kev cai siv roj, resins thiab starch. Nyob rau lub sijhawm dhau los, ntau thiab ntau dua tshiab corrosion inhibitors tau tshwm sim. Tam sim no, tsuas yog nyob rau hauv Russia, koj tuaj yeem suav ntau ntau ntawm lawv cov tuam txhab. Hlau corrosion inhibitors yog dav heev vim lawv tus nqi pheej yig. Lawv muaj txiaj ntsig zoo tshaj plaws hauv cov tshuab uas muaj qhov tsis tu ncua lossis qis ntawm qhov chaw corrosive, xws li tso tsheb hlau luam, tso tsheb hlau luam, tshuab cua txias, chav boilers thiab lwm yam nroj tsuag tshuaj.

Properties

Corrosion inhibitors tuaj yeem yog cov organic lossis inorganic hauv cov xwm txheej. Lawv tuaj yeem tiv thaiv kev kis tau los ntawm cov kua hauv xov xwm lossis cov pa roj. Corrosion inhibitors nyob rau hauv kev lag luam roj nyob rau hauv feem ntau yog txuam nrog inhibition ntawm anodic thiab cathodic txheej txheem ntawm electrochemical puas, tsim ntawm passivating thiab tiv thaiv films. Koj tuaj yeem xav txog qhov tseem ceeb ntawm qhov no.

Anode corrosion inhibitors ua raws li kev ua haujlwm ntawm qhov chaw anodic ntawm cov hlau corroding, uas yog vim li cas rau lub npe passivators. Xws li, nws yog ib txwm muajoxidizing tus neeg sawv cev ntawm inorganic keeb kwm yog siv: nitrates, chromates thiab molybdates. Lawv tau yooj yim txo rau ntawm qhov chaw cathode, uas ua rau lawv zoo ib yam li depolarizers, txo tus nqi ntawm anodic hloov mus rau hauv cov tshuaj uas muaj corrosive hlau ions.

Anode moderators kuj yog qee qhov sib xyaw ua ke uas tsis muaj qhov muaj oxidizing zog: polyphosphates, phosphates, sodium benzoate, silicates. Lawv qhov kev ua raws li inhibitors yog tshwm sim tsuas yog nyob rau hauv lub xub ntiag ntawm oxygen, uas plays lub luag hauj lwm ntawm ib tug passivator. Cov tshuaj no ua rau lub adsorption ntawm oxygen ntawm cov hlau. Tsis tas li ntawd, lawv ua rau inhibition ntawm cov txheej txheem anodic dissolution vim yog tsim ntawm cov yeeb yaj kiab tiv thaiv, uas muaj cov khoom tsis tshua muaj kuab lom ntawm kev sib cuam tshuam ntawm cov inhibitor thiab hlau ions dhau mus rau hauv kev daws teeb meem.

Ntse

Anode corrosion inhibitors ntawm cov hlau feem ntau raug cais raws li kev phom sij, vim tias nyob rau hauv qee qhov xwm txheej lawv tig los ntawm cov neeg saib xyuas mus rau hauv cov txheej txheem kev puas tsuaj. Txhawm rau zam qhov no, nws yog qhov yuav tsum tau ua kom qhov ceev ntawm corrosion tam sim no siab tshaj qhov uas qhov kev ua tiav ntawm cov seem anode yog tsim. Qhov concentration ntawm passivator yuav tsum tsis txhob poob qis dua ib qho nqi, txwv tsis pub passivation yuav tsis tshwm sim, los yog nws yuav ua tsis tiav. Qhov kev xaiv tom kawg yog fraught nrog kev phom sij loj, vim tias nws ua rau txo qis hauv qhov anode nto, qhov nce hauv qhov tob thiab nrawm ntawm cov hlau puas los ntawmthaj chaw me me.

Requirements

Nws hloov tawm tias kev tiv thaiv zoo tuaj yeem muab tau yog tias qhov concentration ntawm anodic inhibitor tau khaws cia siab tshaj tus nqi siab tshaj plaws hauv txhua qhov chaw ntawm cov khoom uas raug tiv thaiv. Cov tshuaj no zoo heev rau pH theem nruab nrab. Chromates thiab nitrates feem ntau yog siv hauv cov khoom siv hluav taws xob sib hloov thiab muab cov yeeb nkab tiv thaiv.

Cathode Inhibitors

Hais txog kev tiv thaiv, cov tshuaj no tsis zoo dua li cov anodic. Lawv qhov kev txiav txim yog raws li qhov tseeb tias hauv zos alkalization ntawm nruab nrab ua rau tsim cov khoom insoluble ntawm cov chaw cathode, uas cais ib feem ntawm qhov chaw los ntawm kev daws teeb meem. Xws li cov khoom muaj peev xwm ua tau, piv txwv li, calcium bicarbonate, uas nyob rau hauv ib qho alkalized nruab nrab tso calcium carbonate nyob rau hauv daim ntawv ntawm precipitate uas nyuaj rau yaj. Lub cathodic corrosion inhibitor, nws muaj pes tsawg leeg nyob ntawm ib puag ncig ntawm kev siv, tsis ua rau muaj kev puas tsuaj ntau ntxiv txawm tias cov ntsiab lus tsis txaus.

Ntau yam

Hauv cov xov xwm nruab nrab, cov tshuaj inorganic feem ntau ua raws li cathodic thiab anodic inhibitors, tab sis nyob rau hauv cov tshuaj acidic heev lawv pab tsis tau. Raws li cov neeg nruab nrab hauv kev tsim cov kua qaub, cov khoom siv organic yog siv, uas cov molecules muaj cov pab pawg tshwj xeeb lossis cov polar pawg, piv txwv li, amines, thiourea, aldehydes, carbonate ntsev thiab phenols.

Raws li lub tshuabCov tshuaj tiv thaiv corrosion sib txawv hauv lawv cov cim adsorption. Tom qab adsorption ntawm cathode lossis anode qhov chaw, lawv cuam tshuam cov paug ntawm hydrogen ions, nrog rau cov tshuaj tiv thaiv hlau ionization. Rau qhov loj, cov nyhuv tiv thaiv yog nyob ntawm qhov kub thiab txias, concentration, hom acid anion, nrog rau cov concentration ntawm hydrogen ions. Lawv feem ntau tau ntxiv rau hauv qhov me me, vim tias qhov kev tiv thaiv ntawm ntau cov organic inhibitors nyob rau hauv siab concentrations txawm yuav txaus ntshai.

Piv txwv li, ib qho organic compound hu ua "Penta-522" yog roj thiab dej soluble. Nws muaj peev xwm muab kev tiv thaiv ntau dua 90% ntawm kev noj tsuas yog 15-25 grams ib tuj. Cov tshuaj tiv thaiv corrosion tsim nyob rau hauv lub cim lag luam "Amincor" yog cov khoom lag luam ntawm esterification ntawm carboxylic acids, uas tsis yog-volatile, tsis muaj ntxhiab tsw, thiab tsis muaj tshuaj lom. Nws qhov ntau npaum li cas tsuas yog txiav txim siab tom qab tsim kom muaj kev cuam tshuam ntawm qhov chaw tiag tiag.

cuam tshuam rau hlau

pab pawg tiv thaiv no suav nrog kev siv ntau yam txheej txheej. Cov no yog cov xim pleev xim, hlau, roj hmab thiab lwm yam. Lawv yog siv nyob rau hauv ntau txoj kev: txau, galvanizing, pos hniav thiab lwm yam. Koj tuaj yeem xav txog lawv txhua tus.

Gumming feem ntau nkag siab tias yog kev tiv thaiv corrosion los ntawm cov roj hmab coatings, uas feem ntau xav tau hauv kev lag luam chlorine. Roj hmab tebchaw muaj zog tshuaj tiv thaiv thiab muab txhim khu kev qha kev tiv thaiv ntawm ntim, da dej, raws li zoo raws li lwm yam khoom siv tshuaj los ntawm raug.aggressive media thiab corrosion. Cov pos hniav yog txias, thiab kub, uas yog ua los ntawm cov txheej txheem ntawm vulcanization ntawm epoxy thiab fluoroplastic mixs.

Nws yog ib qho tseem ceeb tsis yog tsuas yog xaiv kom raug, tab sis kuj siv cov tshuaj tiv thaiv corrosion. Cov neeg tsim khoom feem ntau muab cov lus qhia meej meej txog qhov no. Tam sim no, ntxiv rau galvanic deposition, txoj kev ntawm high-ceev deposition tau dhau los ua heev. Nrog nws cov kev pab, ntau yam kev ua haujlwm ncaj ncees raug daws. Cov ntaub ntawv hmoov tuaj yeem siv tau kom tau cov txheej txheem nrog ntau yam khoom.

khoom siv tiv thaiv

Cov teeb meem cuam tshuam txog kev tiv thaiv cov cuab yeej siv tshuaj yog qhov tshwj xeeb, thiab yog li yuav tsum tau ua tib zoo kawm. Kev xaiv cov khoom siv kom tau txais cov txheej txheem zoo yuav tsum muaj kev soj ntsuam ntawm lub xeev ntawm qhov chaw, qhov muaj pes tsawg leeg ntawm ib puag ncig, kev ua haujlwm, kev ua phem, kev kub ntxhov, thiab lwm yam. Qee zaum, hauv "qhov chaw qis", muaj qhov tseem ceeb uas ua rau nws nyuaj rau xaiv hom kev pab cuam, piv txwv li, steaming txawm ib zaug txhua ob peb lub hlis ntawm lub tank propane. Tias yog vim li cas txhua qhov kev txhoj puab heev yuav tsum tau xaiv cov zaj duab xis qub thiab cov txheej txheem txheej txheem uas yog cov yam ntxwv los ntawm kev tiv thaiv cov reagent.

Muaj kev xav

Cov kws tshaj lij hais tias nws tsis tuaj yeem sib piv cov pa roj cua sov nrog ib leeg, thiab txawm hais tias ib qho zoo dua li lwm tus. Txhua tus ntawm lawv muaj qee qhov zoo thiab qhov tsis zoo, thiab qhov tshwm simcoatings muaj cov khoom sib txawv, uas qhia tias lawv muaj peev xwm daws tau qee yam ntawm lawv txoj haujlwm. Qhov zoo tshaj plaws muaj pes tsawg leeg ntawm cov tshuaj tiv thaiv corrosion yuav tsum yog tus yam ntxwv, nrog rau cov txheej txheem ntawm lawv daim ntawv thov, raug xaiv nyob ntawm qhov tshwj xeeb.

Ntawm cov tuam txhab ntawm kev lag luam tshuaj, txoj kev no feem ntau siv rau hauv cov txheej txheem ntawm kev kho tam sim no. Txawm hais tias siv cov kua qaub corrosion inhibitors, cov hlau saum npoo yuav tsum tau npaj kom zoo. Nov yog tib txoj hauv kev los lav qhov kev pabcuam zoo. Blasting tuaj yeem siv ua ntej siv ncaj qha ntawm cov khoom siv xim kom paub tseeb tias qhov chaw ntxhib txaus.

Txhua xyoo ntau thiab ntau qhov kev txhim kho tshiab tshwm sim hauv khw, thiab muaj kev xaiv ntau heev. Txawm li cas los xij, chemists yuav tsum txiav txim siab seb dab tsi yuav muaj txiaj ntsig ntau dua - txhawm rau ua kom muaj kev tiv thaiv raws sijhawm ntawm cov khoom siv lossis hloov tag nrho cov qauv.