Selenium, monga chinthu chofunikira kwambiri cha semiconductor komanso zopangira mafakitale, imakhudzidwa mwachindunji ndi kuyera kwake. Pa nthawi yoyeretsera vacuum distillation, kuipitsidwa kwa mpweya ndi chimodzi mwazinthu zazikulu zomwe zimakhudza kuyera kwa selenium. Nkhaniyi ikupereka kukambirana mwatsatanetsatane njira zosiyanasiyana ndi njira zochepetsera kuchuluka kwa mpweya panthawi yoyeretsera selenium kudzera mu vacuum distillation.

I. Kuchepetsa Kuchuluka kwa Oxygen mu Gawo Lokonzekera Zinthu Zopangira

1. Kuyeretsa koyambirira kwa Zipangizo Zopangira

Selenium yosaphika nthawi zambiri imakhala ndi zinthu zosiyanasiyana zosafunika, kuphatikizapo ma oxide. Musanalowe mu vacuum distillation system, njira zotsukira mankhwala ziyenera kugwiritsidwa ntchito pochotsa ma oxide pamwamba. Njira zotsukira zomwe zimagwiritsidwa ntchito nthawi zambiri ndi izi:

• Sungunulani yankho la hydrochloric acid (kuchuluka kwa 5-10%): Imasungunula bwino ma oxide monga SeO₂
• Ethanol kapena acetone: Amagwiritsidwa ntchito kuchotsa zinthu zodetsa zachilengedwe
• Madzi oyeretsedwa: Kutsuka kangapo kuti muchotse asidi wotsala

Mukamaliza kuyeretsa, kuumitsa kuyenera kuchitika pansi pa mpweya wopanda mpweya (monga Ar kapena N₂) kuti mupewe kubwereranso kwa okosijeni.

2. Kukonza Zinthu Zopangira Pasadakhale

Kuchepetsa mankhwala opangira zinthu zopangira musanagwiritse ntchito vacuum distillation kungachepetse kwambiri kuchuluka kwa mpweya m'thupi:

• Kuchepetsa haidrojeni: Kuyika haidrojeni yoyera kwambiri (yoyera ≥99.999%) pa 200-300°C kuti muchepetse SeO₂ kukhala selenium yoyambira
• Kuchepetsa kutentha kwa thupi: Sakanizani zinthu zopangira selenium ndi ufa wa kaboni woyeretsedwa kwambiri ndikutentha mpaka 400-500°C pansi pa vacuum kapena mpweya wopanda mpweya, zomwe zimapangitsa kuti C + SeO₂ → Se + CO₂ iyambe kugwira ntchito.
• Kuchepetsa sulfide: Mpweya monga H₂S ukhoza kuchepetsa selenium oxides pa kutentha kochepa

II. Kapangidwe ndi Kukonza Bwino Kachitidwe ka Vacuum Distillation

1. Kusankha ndi Kusintha kwa Dongosolo la Vacuum

Malo okhala ndi mpweya wambiri ndi ofunikira kwambiri pochepetsa mpweya woipa:

• Gwiritsani ntchito pampu yofalitsa ndi makina osakaniza, ndi vacuum yokwanira kufika pa 10⁻⁴ Pa
• Dongosololi liyenera kukhala ndi chotchingira chozizira kuti nthunzi ya mafuta isafalikire m'mbuyo.
• Malumikizidwe onse ayenera kugwiritsa ntchito zomangira zachitsulo kuti apewe kutulutsa mpweya kuchokera ku zomangira za rabara.
• Dongosololi liyenera kuchotsedwa mpweya wokwanira (200-250°C, maola 12-24)

2. Kulamulira Molondola Kutentha ndi Kupanikizika kwa Distillation

Kuphatikiza kwabwino kwambiri kwa magawo a njira:

• Kutentha kwa distillation: Kumayendetsedwa mkati mwa 220-280°C (pansi pa kutentha kwa selenium kwa 685°C)
• Kupanikizika kwa dongosolo: Kusungidwa pakati pa 1-10 Pa
• Kutentha: 5-10°C/mphindi kuti tipewe kupsa ndi kulowetsedwa m'madzi mwamphamvu
• Kutentha kwa malo oundana: Kusungidwa pa 50-80°C kuti selenium ikhazikike bwino

3. Ukadaulo Wothira Zinthu Zosiyanasiyana

Kutulutsa mpweya m'magawo ambiri kungachepetse pang'onopang'ono kuchuluka kwa mpweya m'thupi:

• Gawo loyamba: Kusungunula mopanda mphamvu kuti muchotse zinyalala zambiri zosasunthika
• Gawo lachiwiri: Kuwongolera kutentha kolondola kuti musonkhanitse gawo lalikulu
• Gawo lachitatu: Kutentha kochepa, kusungunuka pang'onopang'ono kuti mupeze chinthu choyera kwambiri
  Kutentha kosiyanasiyana kwa condensation kungagwiritsidwe ntchito pakati pa magawo kuti condensation ya fractional igwiritsidwe ntchito

III. Njira Zothandizira

1. Ukadaulo Woteteza Mpweya Wopanda Mphamvu

Ngakhale kuti imagwira ntchito pansi pa vacuum, kuyambika koyenera kwa mpweya wopanda mpweya wabwino kwambiri kumathandiza kuchepetsa kuchuluka kwa mpweya m'thupi:

• Mukatha kutuluka mu dongosololi, dzazani ndi argon yoyera kwambiri (yoyera ≥99.9995%) mpaka 1000 Pa
• Gwiritsani ntchito chitetezo cha mpweya wothamanga, nthawi zonse muwonjezere pang'ono argon (10-20 sccm)
• Ikani zotsukira mpweya zogwira ntchito bwino kwambiri pamalo olowera mpweya kuti muchotse mpweya wotsala ndi chinyezi

2. Kuwonjezera Zokoka Mpweya wa Oxygen

Kuwonjezera zinthu zoyenera zochotsera mpweya ku zinthu zopangira kungathandize kuchepetsa mpweya woipa:

• Chitsulo cha Magnesium: Kugwirizana kwakukulu kwa mpweya, kupanga MgO
• Ufa wa aluminiyamu: Ungathe kuchotsa mpweya ndi sulfure nthawi imodzi
• Zitsulo zosowa zapadziko lapansi: Monga Y, La, ndi zina zotero, zomwe zimakhala ndi zotsatira zabwino kwambiri zochotsa mpweya.
  Kuchuluka kwa okosijeni wochotsa mpweya nthawi zambiri kumakhala 0.1-0.5% ya zinthu zopangira; kuchuluka kochulukirapo kungakhudze kuyera kwa selenium

3. Ukadaulo Wosefera Wosungunuka

Kusefa selenium yosungunuka musanayeretsedwe:

• Gwiritsani ntchito zosefera za quartz kapena ceramic zokhala ndi ma pore a 1-5 μm
• Sinthani kutentha kwa kusefera pa 220-250°C
• Ikhoza kuchotsa tinthu tating'onoting'ono tolimba ta oxide
• Zosefera ziyenera kutsukidwa kale ndi mpweya pansi pa vacuum yambiri

IV. Kusunga ndi Kuchiza Pambuyo pa Chithandizo

1. Kusonkhanitsa ndi Kusamalira Zinthu

• Chosonkhanitsira condenser chiyenera kupangidwa ngati kapangidwe kotha kuchotsedwa kuti zinthu zipezeke mosavuta pamalo opanda madzi.
• Ma ingot a selenium osonkhanitsidwa ayenera kupakidwa mu bokosi la magolovesi a argon
• Kudula pamwamba kungachitike ngati kuli kofunikira kuti muchotse zigawo zomwe zingatheke za oxide

2. Kuwongolera Mkhalidwe Wosungirako

• Malo osungiramo zinthu ayenera kukhala ouma (mame ≤-60°C)
• Gwiritsani ntchito ma phukusi otsekedwa okhala ndi magawo awiri odzazidwa ndi mpweya woipa kwambiri
• Kutentha koyenera kosungirako pansi pa 20°C
• Pewani kuyatsidwa ndi kuwala kuti mupewe kusintha kwa ma photocatalytic oxidation

V. Kuwongolera ndi Kuyesa Ubwino

1. Ukadaulo Wowunikira Paintaneti

• Ikani zoyezera mpweya wotsalira (RGA) kuti ziwunikire mpweya pang'ono panthawi yeniyeni
• Gwiritsani ntchito masensa a okosijeni kuti muwongolere kuchuluka kwa okosijeni m'mipweya yoteteza
• Gwiritsani ntchito infrared spectroscopy kuti mudziwe nsonga zoyamwa za Se-O bonds

2. Kusanthula kwa Zogulitsa Zomalizidwa

• Gwiritsani ntchito njira yoyamwitsa mpweya wa inert fusion-infrared kuti mudziwe kuchuluka kwa mpweya
• Masekondi a ion mass spectrometry (SIMS) kuti afufuze kugawa kwa okosijeni
• X-ray photoelectron spectroscopy (XPS) kuti izindikire momwe mankhwala alili pamwamba

Kudzera mu miyeso yonse yomwe yafotokozedwa pamwambapa, kuchuluka kwa mpweya kumatha kulamulidwa pansi pa 1 ppm panthawi yoyeretsera selenium pogwiritsa ntchito vacuum distillation, kukwaniritsa zofunikira pakugwiritsa ntchito selenium yoyera kwambiri. Pakupanga kwenikweni, magawo a njira ayenera kukonzedwa kutengera momwe zida zimagwirira ntchito komanso zofunikira pa malonda, ndipo njira yowongolera khalidwe iyenera kukhazikitsidwa.