Photovoltaic-tsav Dual-oxidation Seawater Electrolyzer Rau Sustainable Lithium Recovery

Kab lus no yog hais txog ib qho tshiab electrochemical "dual-oxidation" seawater electrolysis system uas ua tiav lithium rov qab los ntawm kev sib txuas electrode oxidation thiab electrolyte oxidation. Kev tshawb fawb tau koom ua ke los ntawm cov kws tshawb fawb los ntawm Southern University of Science thiab Technology, Central South University, Ningbo Oriental Polytechnic University, thiab Shenzhen Lub Tsev Kawm Ntawv ntawm Kev Tshawb Fawb Txog Hluav Taws Xob. Tshaj tawm hauv Kev Ua Haujlwm ntawm National Academy of Sciences (PNAS), tsab xov xwm qhia txog lub zog qis, siab-lithium rov qab thev naus laus zis uas tseem ceeb heev rau kev hais txog qhov kev thov loj hlob rau lithium thiab txo cov pa roj carbon hneev taw.

Nrog rau kev xav tau ntau ntxiv rau lithium hauv cov khoom siv hluav taws xob khaws cia, cov txheej txheem kev rho tawm ib txwm siv xws li thermal metallurgy thiab hydrometallurgy tau dhau los ua kev tshuaj xyuas ntau ntxiv rau lawv cov hneev taw ib puag ncig thiab CO2 emissions loj.

Cov txheej txheem no tsis yog tsuas yog siv lub zog siv xwb tab sis kuj siv cov tshuaj lom neeg muaj kev phom sij, ua rau muaj kev txhawj xeeb txog kev ruaj khov thiab cov peev txheej depletion. Lub koom haum International Energy Agency (IEA) kwv yees tias cov mines uas twb muaj lawm tsuas tuaj yeem ua tau raws li ib nrab ntawm lithium kev lag luam xav tau los ntawm 2030, qhia txog qhov ceev ntawm kev nrhiav kom huv thiab muaj txiaj ntsig zoo lithium rov qab txoj hauv kev.

Cov kws tshawb fawb tau npaj ib qho electrochemical "dual oxidation" seawater electrolysis system uas ua tiav cov pa roj carbon tsawg thiab siab lithium rov qab los ntawm kev sib txuas electrode oxidation thiab electrolyte oxidation. Lawv tau pom lithium rov qab los ntawm cov khoom pov tseg LiFePO4 cathode nrog tus nqi rov qab ntawm 98.96% thiab cov khoom purity ntawm 99.60%.

Los ntawm cov kev tshawb fawb hauv qhov tob, nws tau pom tias cov hluav taws xob hluav taws xob-tsav electrode oxidation thiab hauv-situ generated oxidative electrolyte synergistically txhawb cov leaching ntawm lithium ions los ntawm kev sib koom ua ke ntawm cov qauv txheej txheem oxidation thiab particle corrosion splitting.

Qhov no dual oxidation mechanism txhawb kev ceev thiab zoo lithium extraction, muaj dav thoob ntiaj teb, thiab muab kev lag luam thiab ib puag ncig zoo.

Cov txiaj ntsig kev sim qhia tau hais tias qhov kev ua haujlwm oxidation dual no nthuav tawm sai dua kinetics thiab ntau dua lithium leaching efficiency hauv cov electrolytes sib txawv piv nrog cov tshuaj electrochemical lithium leaching txoj kev.

Tshwj xeeb, hauv NaCl electrolyte, lithium leaching efficiency tau mus txog 88.7% hauv 40 feeb, uas yog ntau dua li ntawm Na2SO4 thiab NaNO3 electrolytes.

Tsis tas li ntawd, qhov kev sim kuj pom tau tias nrog kev nce ntawm Cl⁻ concentration, leaching kinetics ntawm lithium accelerated, qhia tias cov tshuaj chlorine nquag tsim los ntawm electrocatalytic oxidation tuaj yeem txhawb kev sib cais ntawm LiFePO4 hais, yog li txhim kho cov leaching kinetics ntawm Li⁺.

Cov kws tshawb fawb kuj tau kawm txog atomic-level structural evolution ntawm electrode thaum lub sij hawm lithium leaching los ntawm cov tswv yim xws li nyob rau hauv situ hmoov X-ray diffraction (XRD), nyob rau hauv situ kis electron microscopy (TEM), electron zog poob spectroscopy (EELS) thiab X- ray photoelectron spectroscopy (XPS).

Cov tswv yim no tau qhia txog kev hloov pauv ntawm cov qauv siv lead ua dynamic ntawm LiFePO4 thaum lub sij hawm oxidation dual txheej txheem, uas Li⁺ tau ntsib ib feem leaching thiab teeb meem nyob rau hauv LiFePO4 thiab thaum kawg kiag li khiav tawm ntawm lub moj khaum channel.

1. Universality ntawm dual oxidation mechanism

Txhawm rau ntsuas qhov siv tau dav dua ntawm cov txheej txheem no, cov kws tshawb fawb tau ua qhov kev sim leaching ntawm cov lithium sib txawv hauv 0.50 M NaCl electrolyte, suav nrog cov roj teeb lithium-ion pov tseg uas muaj LiCoO2, LiMn2O4, Li (NixCoyMnz) O2 thiab lithium-muaj. ntxhia spodumene.

Cov txiaj ntsig kev sim qhia tau hais tias qhov kev ua haujlwm oxidation dual no nthuav tawm cov txiaj ntsig zoo lithium leaching efficiency nyob rau hauv cov sib txawv lithium hosts, ua kom pom nws txoj kev siv dav hauv kev ruaj ntseg lithium rov qab.

2. Electrochemical seawater electrolysis system

Cov kws tshawb nrhiav txuas ntxiv ua ke no ob lub oxidation mechanism nrog photovoltaic panels los tsav lithium leaching los ntawm pov tseg LiFePO4. Siv cov khoom siv hluav taws xob ntau hauv dej hiav txwv, lawv tau pom tias lub kaw lus tuaj yeem ua tiav 94.87% lithium leaching efficiency hauv thawj theem ntawm siab NaCl concentrations.

Hauv theem thib ob, cov electrodes tau tso rau hauv qhov chaw tsim hluav taws xob oxidizing electrolyte rau 10 teev, thiab qhov kawg lithium leaching efficiency tuaj yeem txhim kho ntxiv mus rau 98.96%. Tag nrho lub cev tsuas yog yuav tsum tau siv lub zog ntawm 0.054 kWh kg⁻¹ kom rov qab tau 1.0 kg ntawm LiFePO4 pov tseg, tsis tas siv cov tshuaj lom neeg lossis CO2 emissions.

3. Cov txiaj ntsig ib puag ncig thiab kev ntsuas kev lag luam thiab kev lag luam

Cov kws tshawb fawb tau ua tiav cov txiaj ntsig ib puag ncig thiab kev soj ntsuam kev lag luam thiab kev lag luam ntawm no electrochemical multi-channel leaching system thiab txheej txheem rov qab.

Piv nrog rau cov txheej txheem thermometallurgical thiab hydrometallurgical, lub kaw lus muaj kev nyab xeeb dua thiab muaj kev nyab xeeb dua ib puag ncig los ntawm kev txo qis kev siv hluav taws xob thiab cov pa hluav taws xob hauv tsev cog khoom thaum nce lithium selectivity thiab leaching tus nqi.

Los ntawm kev xav txog techno-economic, cov kws tshawb fawb tau tshuaj xyuas kom meej tag nrho cov nqi cuam tshuam thiab cov nyiaj tau los, suav nrog cov nqi pov tseg LiFePO4 hmoov, kev siv hluav taws xob, cov khoom siv poob qis, kev siv tshuaj reagent, thiab cov nyiaj tau los ntawm cov khoom siv rov qab.

Kev tshuaj xyuas tau pom tias tag nrho cov nqi peev ntawm kev rov qab lithium los ntawm 1. FePO4 thiab kev txuag hluav taws xob, ua rau muaj txiaj ntsig tag nrho ntawm $ 1.41 / kg, qhia txog kev lag luam muaj txiaj ntsig ntawm dual-oxide lithium leaching thiab rov qab txheej txheem.

Qhov no electrochemical dual-oxide electrolysis system ua tiav sai thiab muaj txiaj ntsig lithium rov qab los ntawm ntau yam lithium-bearing khoom matrices siv seawater. Atomic-theem characterization qhia lub mechanism ntawm synergistic kev txiav txim ntawm hluav taws xob teb thiab nyob rau hauv-situ generated oxidants. Qhov no dual oxidation mechanism muaj peev xwm ua tau zoo rau kev rov qab zoo ntawm lithium los ntawm ntau yam pov tseg lithium-ion roj teeb thiab cov zaub mov, thiab nws cov scalability yuav tsum tau siv dav hauv kev rho tawm ntawm lwm cov hlau tseem ceeb yav tom ntej, suav nrog ntsuab rho tawm ntawm cov hlau tseem ceeb ncaj qha los ntawm natural minerals thiab lwm yam mines hauv nroog.

Txoj kev teeb pom kev zoo ib puag ncig no tsis tsuas yog txhim kho ib puag ncig kev ruaj ntseg, tab sis kuj txhim kho kev lag luam, txo qis carbon emissions piv nrog cov txheej txheem ib txwm muaj. Ntau qhov dav, qhov system no ua rau txoj hauv kev rau lub voj voog kaw, ruaj khov lithium voj voog uas yog carbon-nruab nrab nyob rau hauv cov ntug dej hiav txwv.