Kukonzekera kwa ultrafine rare earth oxides

Kukonzekera kwaultrafine rare earth oxides

Mitundu yapadziko lapansi ya Ultrafine yosowa kwambiri imakhala ndi ntchito zambiri poyerekeza ndi mitundu yosowa yapadziko lapansi yokhala ndi kukula kwa tinthu tating'ono, ndipo pakali pano pali kafukufuku wambiri pa izo. Njira zokonzekera zimagawidwa m'njira yolimba, njira yamadzimadzi, ndi njira ya gasi malinga ndi momwe zinthu ziliri. Pakali pano, njira yamadzimadzi imagwiritsidwa ntchito kwambiri m'ma laboratories ndi mafakitale pokonzekera ufa wochuluka wamitundu yosowa padziko lapansi. Zimaphatikizapo njira ya mpweya, njira ya sol gel, njira ya hydrothermal, njira ya template, njira ya microemulsion ndi njira ya alkyd hydrolysis, yomwe njira ya mpweya ndiyo yabwino kwambiri yopanga mafakitale.

The mpweya njira ndi kuwonjezera precipitant ku zitsulo mchere njira mpweya, ndiyeno sefa, kuchapa, youma ndi kutentha kuwola kupeza mankhwala ufa. Zimaphatikizapo njira ya mvula yachindunji, njira yofanana ya mvula ndi njira yowongoka. Mu njira wamba mpweya, osowa nthaka oxides ndi osowa mchere mchere wokhala ndi kusakhazikika asidi ankafuna kusintha zinthu mopitirira muyeso angapezeke mwa kuwotcha mpweya, ndi tinthu kukula 3-5 μ m. Malo enieni ndi osakwana 10 ㎡/g ndipo alibe mphamvu zapadera komanso mankhwala. Njira ya mpweya wa ammonium carbonate ndi njira ya mpweya wa oxalic acid ndi njira zomwe zimagwiritsidwa ntchito kwambiri popangira ufa wamba wa okusayidi, ndipo bola ngati njira yamvula ikasinthidwa, imatha kugwiritsidwa ntchito pokonzekera ufa wa ultrafine rare earth oxide.

Kafukufuku wawonetsa kuti zinthu zazikulu zomwe zimakhudza kukula kwa tinthu ndi kapangidwe kazinthu zamitundu yosowa kwambiri padziko lapansi mu njira ya ammonium bicarbonate mpweya ndi monga kuchuluka kwa dziko lapansi munjira, kutentha kwa mpweya, ndende ya mpweya, ndi zina zambiri. njira yothetsera ndiye chinsinsi kupanga uniformly omwazika ufa ultrafine. Mwachitsanzo, pakuyesa kwa mpweya wa Y3 + kukonzekera Y2O3, pamene kuchuluka kwa dziko losowa kwambiri ndi 20 ~ 30g/L (kuwerengedwa ndi Y2O3), njira yamvula imakhala yosalala, ndipo ufa wa yttrium oxide ultrafine umachokera ku carbonate precipitation. kuyanika ndi kuyatsa ndi kochepa, kofanana, ndipo Disperity ndi yabwino.

Mu zochita za mankhwala, kutentha ndi chinthu chotsimikizika. Muzoyesera zomwe tatchulazi, kutentha kukakhala 60-70 ℃, mpweya umakhala wodekha, kusefera kumathamanga, tinthu tating'onoting'ono tating'onoting'ono tating'onoting'ono tating'onoting'ono, ndipo timakhala tozungulira; Pamene kutentha kwake kuli pansi pa 50 ℃, mvula imapanga mofulumira, ndi mbewu zambiri ndi tinthu tating'onoting'ono. Panthawiyi, kuchuluka kwa CO2 ndi NH3 kusefukira kumakhala kochepa, ndipo mvula imakhala yomata, yomwe si yoyenera kusefa ndi kuchapa. Pambuyo kuwotchedwa mu yttrium okusayidi, pali blocky zinthu kuti agglomerate kwambiri ndi zazikulu tinthu kukula kwake. Kuchuluka kwa ammonium bicarbonate kumakhudzanso kukula kwa yttrium oxide. Pamene ndende ya ammonium bicarbonate ndi zosakwana 1mol/L, analandira yttrium okusayidi tinthu kukula ndi yaing'ono ndi yunifolomu; Pamene ndende ya ammonium bicarbonate kuposa 1mol/L, m'deralo mpweya zidzachitika, kuchititsa agglomeration ndi zikuluzikulu particles. Pazikhalidwe zoyenera, tinthu kukula kwa 0.01-0.5 angapezeke μ M ultrafine yttrium okusayidi ufa.

Mu oxalate mpweya njira, ndi oxalic asidi njira anawonjezera dropwise pamene ammonia ndi anawonjezera kuonetsetsa zonse pH phindu pa zimene ndondomeko, chifukwa mu tinthu kukula zosakwana 1 μ M wa yttrium okusayidi ufa. Choyamba, precipitate yttrium nitrate njira ndi ammonia madzi kupeza yttrium hydroxide colloid, ndiyeno kusintha ndi oxalic asidi njira kupeza tinthu kukula zosakwana 1 μ Y2O3 ufa wa m. Onjezani EDTA ku Y3 + solution ya yttrium nitrate yokhala ndi 0.25-0.5mol/L, sinthani pH mpaka 9 ndi madzi ammonia, onjezerani ammonium oxalate, ndikudontha njira ya 3mol/L HNO3 pamlingo wa 1-8mL/ mphindi pa 50 ℃ mpaka mvula itakwanira pH = 2. Yttrium okusayidi ufa ndi tinthu kukula 40-100nm angapezeke.

Panthawi yokonzekeraultrafine rare earth oxidesndi njira yamvula, magawo osiyanasiyana a agglomeration amatha kuchitika. Choncho, pakukonzekera ndondomeko m`pofunika mosamalitsa kulamulira zinthu kaphatikizidwe, ndi kusintha pH mtengo, ntchito precipitants osiyana, kuwonjezera dispersants, ndi njira zina mokwanira kumwazikana mankhwala wapakatikati. Kenako, njira zoyanika zoyenera zimasankhidwa, ndipo pamapeto pake, ma ufa osowa kwambiri padziko lapansi omwe amamwazikana amapezedwa kudzera mu calcination.