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Gawo la msika wa makina oziziritsira madzi odzazidwa ndi madzi ndi mapampu otenthetsera likadali laling'ono poyerekeza ndi makina achikhalidwe oziziritsira madzi. Ngakhale kuti pali ubwino waukulu wogwiritsa ntchito kutentha kotsika mtengo (m'malo mwa ntchito zamagetsi zodula), kugwiritsa ntchito makina ozikidwa pa mfundo zoziziritsira madzi kumangokhala ndi ntchito zingapo zapadera. Choyipa chachikulu chomwe chikufunika kuchotsedwa ndi kuchepa kwa mphamvu inayake chifukwa cha kutentha kochepa komanso kukhazikika kochepa kwa adsorbent. Makina oziziritsira madzi opangidwa ndi mafakitale amakono amachokera ku adsorbers kutengera ma plate heat exchangers ophimbidwa kuti azitha kuziziritsa bwino. Zotsatira zake zimadziwika bwino kuti kuchepetsa makulidwe a chophimbacho kumabweretsa kuchepa kwa mass transfer impedance, ndipo kuwonjezera chiŵerengero cha malo pamwamba pa voliyumu ya ma conductive structures kumawonjezera mphamvu popanda kusokoneza magwiridwe antchito. Ulusi wachitsulo womwe umagwiritsidwa ntchito pantchitoyi ukhoza kupereka malo enaake pamtunda wa 2500–50,000 m2/m3. Njira zitatu zopezera ma hydrate amchere ochepa kwambiri komanso okhazikika pamwamba pa zitsulo, kuphatikiza ulusi wachitsulo, popanga ma coverage zikuwonetsa koyamba kuti pali chosinthira kutentha champhamvu kwambiri. Chithandizo cha pamwamba chomwe chimachokera ku anodizing ya aluminiyamu chimasankhidwa kuti chipange mgwirizano wolimba pakati pa chophimbacho ndi substrate. Kapangidwe kake ka pamwamba pake kanawunikidwa pogwiritsa ntchito microscopy ya electron scanning. Kuchepetsa chiwonetsero chonse cha Fourier transform infrared spectroscopy ndi energy dispersive X-ray spectroscopy zinagwiritsidwa ntchito kuti ziwone ngati pali mtundu womwe ukufunidwa mu assay. Kuthekera kwawo kupanga ma hydrate kunatsimikiziridwa ndi kusanthula kwa thermogravimetric (TGA)/differential thermogravimetric analysis (DTG). Ubwino wochepa kuposa 0.07 g (madzi)/g (composite) unapezeka mu chophimba cha MgSO4, kuwonetsa zizindikiro za kutaya madzi pa kutentha kwa pafupifupi 60 °C ndipo zimabwereranso pambuyo pobwezeretsanso madzi. Zotsatira zabwino zinapezekanso ndi SrCl2 ndi ZnSO4 ndi kusiyana kwa kulemera kwa pafupifupi 0.02 g/g pansi pa 100 °C. Hydroxyethylcellulose inasankhidwa ngati chowonjezera kuti chiwonjezere kukhazikika ndi kumamatira kwa chophimbacho. Katundu wokometsera wa zinthuzi adawunikidwa ndi TGA-DTG nthawi imodzi ndipo kumatirira kwawo kudadziwika ndi njira yochokera ku mayeso omwe afotokozedwa mu ISO2409. Kukhazikika ndi kumatirira kwa chophimba cha CaCl2 kumawonjezeka kwambiri pamene kumasunga mphamvu yake yokometsera ndi kusiyana kwa kulemera kwa pafupifupi 0.1 g/g pa kutentha pansi pa 100 °C. Kuphatikiza apo, MgSO4 imasunga mphamvu yopangira ma hydrate, kuwonetsa kusiyana kwa unyinji woposa 0.04 g/g pa kutentha pansi pa 100 °C. Pomaliza, ulusi wachitsulo wokutidwa umawunikidwa. Zotsatira zake zikuwonetsa kuti kutentha koyenera kwa kapangidwe ka ulusi wokutidwa ndi Al2(SO4)3 kungakhale kokwera nthawi 4.7 poyerekeza ndi kuchuluka kwa Al2(SO4)3 yoyera. Kukutira kwa chophimba chomwe chaphunziridwachi kudawunikidwa m'maso, ndipo kapangidwe ka mkati kadawunikidwa pogwiritsa ntchito chithunzi cha microscopic cha magawo opingasa. Kukutira kwa Al2(SO4)3 kokhala ndi makulidwe pafupifupi 50 µm kudapezeka, koma njira yonse iyenera kukonzedwa bwino kuti ikwaniritse kufalikira kofanana.
Machitidwe olowetsa madzi m'malo osungira madzi atchuka kwambiri m'zaka makumi angapo zapitazi chifukwa amapereka njira ina yabwino yosungira madzi m'malo mwa makina otenthetsera kapena makina oziziritsira. Chifukwa cha kukwera kwa miyezo yabwino komanso kutentha kwapakati padziko lonse lapansi, makina olowetsa madzi m'malo osungira ...
Mapampu otentha olowetsa madzi ndi makina oziziritsira amatsatira njira yofanana ya thermodynamic monga momwe amachitira ndi nthunzi. Kusiyana kwakukulu ndikusintha kwa zigawo za compressor ndi ma adsorber. Chinthuchi chimatha kunyamula nthunzi yoziziritsira yotsika kwambiri kutentha pang'ono, ndikutulutsa nthunzi yambiri mufiriji ngakhale madziwo ali ozizira. Ndikofunikira kuonetsetsa kuti adsorber ikuzizira nthawi zonse kuti achotse enthalpy ya adsorption (exotherm). Adsorber imapangidwanso kutentha kwambiri, zomwe zimapangitsa kuti nthunzi ya refrigerant ichotse sorbency. Kutentha kuyenera kupitiliza kupereka enthalpy ya desorption (endothermic). Chifukwa njira zolowetsera madzi zimadziwika ndi kusintha kwa kutentha, mphamvu zambiri zimafuna kuti kutentha kukhale kokwera. Komabe, kutentha kochepa ndiye vuto lalikulu pa ntchito zambiri.
Vuto lalikulu la conductivity ndi kuwonjezera mtengo wake wapakati pamene mukusunga njira yoyendera yomwe imapereka kuyenda kwa nthunzi zoyamwa/kuchotsa madzi. Njira ziwiri zimagwiritsidwa ntchito kwambiri kuti izi zitheke: zosinthira kutentha zophatikizika ndi zosinthira kutentha zophimbidwa. Zipangizo zophatikizika zodziwika bwino komanso zopambana ndi zomwe zimagwiritsa ntchito zowonjezera zochokera ku kaboni, zomwe ndi graphite yowonjezereka, kaboni woyatsidwa, kapena ulusi wa kaboni. Oliveira et al. 2 wothira ufa wowonjezera wa graphite ndi calcium chloride kuti apange adsorber yokhala ndi mphamvu yoziziritsira (SCP) yofika 306 W/kg ndi coefficient of performance (COP) yofika 0.46. Zajaczkowski et al. 3 adapereka lingaliro lophatikiza graphite yowonjezereka, ulusi wa kaboni ndi calcium chloride yokhala ndi conductivity yonse ya 15 W/mK. Jian et al4 adayesa zophatikizika ndi sulfuric acid yothandizidwa ndi graphite yachilengedwe yowonjezereka (ENG-TSA) ngati substrate mu nthawi yozizira yoyamwa ya magawo awiri. Chitsanzocho chinaneneratu kuti COP idzachokera pa 0.215 mpaka 0.285 ndi SCP kuchokera pa 161.4 mpaka 260.74 W/kg.
Njira yabwino kwambiri yothetsera vutoli ndi chotenthetsera kutentha chophimbidwa. Njira zophikira za zotenthetsera izi zitha kugawidwa m'magulu awiri: kupanga mwachindunji ndi zomatira. Njira yopambana kwambiri ndi kupanga mwachindunji, komwe kumaphatikizapo kupanga zinthu zomatira mwachindunji pamwamba pa zotenthetsera kutentha kuchokera ku ma reagents oyenera. Sotech5 yapanga njira yopangira zeolite yokutidwa kuti igwiritsidwe ntchito mu zoziziritsira zingapo zopangidwa ndi Fahrenheit GmbH. Schnabel et al6 adayesa momwe ma zeolite awiri yokutidwa pa chitsulo chosapanga dzimbiri amagwirira ntchito. Komabe, njira iyi imagwira ntchito ndi zomatira zinazake, zomwe zimapangitsa kuti kupaka ndi zomatira kukhala njira ina yosangalatsa. Zomatira ndi zinthu zosagwiritsidwa ntchito zomwe zimasankhidwa kuti zithandizire kumatira kwa sorbent ndi/kapena kusamutsa kuchuluka, koma sizigwira ntchito pakukweza kapena kukweza mphamvu yamagetsi. Freni et al. 7 zomatira zotenthetsera za aluminiyamu zokhala ndi AQSOA-Z02 zeolite zokhazikika ndi chomatira chopangidwa ndi dongo. Calabrese et al.8 adaphunzira za kukonzekera zomatira za zeolite zokhala ndi zomatira za polymeric. Ammann ndi anzake 9 adapereka njira yokonzekera zokutira za zeolite zokhala ndi porous kuchokera ku maginito osakaniza a polyvinyl alcohol. Alumina (alumina) imagwiritsidwanso ntchito ngati binder 10 mu adsorber. Monga momwe tikudziwira, cellulose ndi hydroxyethyl cellulose zimagwiritsidwa ntchito pokhapokha kuphatikiza ndi adsorbents physical11,12. Nthawi zina guluu sagwiritsidwa ntchito pa utoto, koma amagwiritsidwa ntchito kumanga kapangidwe kake 13 kokha. Kuphatikiza kwa alginate polymer matrices ndi ma salt hydrate ambiri kumapanga mapangidwe osinthasintha a bead omwe amaletsa kutuluka kwa madzi panthawi youma ndikupereka kusamutsa kokwanira. Dongo monga bentonite ndi attapulgite lagwiritsidwa ntchito ngati binder pokonzekera composites15,16,17. Ethylcellulose yagwiritsidwa ntchito poyika microcapsulate calcium chloride18 kapena sodium sulfide19.
Ma composite okhala ndi kapangidwe ka chitsulo chopindika amatha kugawidwa m'magawo osinthira kutentha ndi ma heat exchanger okhala ndi zokutira. Ubwino wa mapangidwe awa ndi malo apamwamba kwambiri. Izi zimapangitsa kuti pakhale malo olumikizirana pakati pa adsorbent ndi chitsulo popanda kuwonjezerapo chinthu chosagwira ntchito, zomwe zimachepetsa kugwira ntchito bwino kwa nthawi yoziziritsira. Lang et al. 20 akweza mphamvu yonse ya zeolite adsorber yokhala ndi kapangidwe ka chitsulo cha aluminiyamu. Gillerminot et al. 21 akweza mphamvu ya kutentha ya zigawo za NaX zeolite ndi thovu la mkuwa ndi nickel. Ngakhale kuti ma composites amagwiritsidwa ntchito ngati zinthu zosintha magawo (PCMs), zomwe Li et al. 22 ndi Zhao et al. 23 apezanso chidwi pa chemisorption. Anayerekeza magwiridwe antchito a graphite yowonjezereka ndi thovu lachitsulo ndipo adatsimikiza kuti yomalizayi inali yabwino pokhapokha ngati dzimbiri silinali vuto. Palomba et al. Posachedwapa adayerekeza mapangidwe ena achitsulo opindika24. Van der Pal et al. aphunzira mchere wachitsulo womwe uli mu thovu 25. Zitsanzo zonse zam'mbuyomu zikugwirizana ndi zigawo zokhuthala za tinthu tating'onoting'ono tomwe timatulutsa timadzi timeneti. Mapangidwe achitsulo okhala ndi machubu sagwiritsidwa ntchito pophimba ma adsorber, zomwe ndi njira yabwino kwambiri. Chitsanzo cha kumangirira ku zeolites chingapezeke mu Wittstadt et al. 26 koma palibe kuyesa komwe kwachitika komanga ma hydrate amchere ngakhale kuti ali ndi mphamvu zambiri 27.
Motero, njira zitatu zokonzekera zophimba za adsorbent zidzafufuzidwa m'nkhaniyi: (1) chophimba cha binder, (2) reaction yolunjika, ndi (3) chithandizo cha pamwamba. Hydroxyethylcellulose inali chogwirira ntchito chomwe chinali chosankhidwa kwambiri pantchitoyi chifukwa cha kukhazikika komwe kunanenedwa kale komanso kumamatira bwino kwa chophimba pamodzi ndi zophimba zakuthupi. Njirayi poyamba idafufuzidwa za zophimba zathyathyathya ndipo pambuyo pake idagwiritsidwa ntchito kuzinthu zachitsulo. Poyamba, kusanthula koyambirira kwa kuthekera kwa zochita zamakemikolo ndi mapangidwe a zophimba za adsorbent kunanenedwa. Zomwe zidachitika kale tsopano zikusamutsidwira ku chophimba chazinthu zachitsulo. Chithandizo cha pamwamba chomwe chasankhidwa pa ntchitoyi ndi njira yozikidwa pa anodizing ya aluminiyamu. Anodizing ya aluminiyamu yaphatikizidwa bwino ndi mchere wachitsulo kuti ikongoletse29. Pazochitika izi, zophimba zokhazikika komanso zosagwira dzimbiri zitha kupezeka. Komabe, sizingathe kuchita njira iliyonse yotsatsira kapena kuchotsa. Pepalali likuwonetsa njira yosiyana iyi yomwe imalola kuti unyinji usunthidwe pogwiritsa ntchito zinthu zomatira za njira yoyambirira. Monga momwe tikudziwira, palibe njira iliyonse yomwe yafotokozedwa pano yomwe yaphunziridwa kale. Zikuyimira ukadaulo watsopano wosangalatsa kwambiri chifukwa zimalola kupangidwa kwa zokutira zosungunuka ndi madzi, zomwe zili ndi zabwino zingapo poyerekeza ndi zosungunuka zomwe zimaphunziridwa kawirikawiri.
Mapepala a aluminiyamu osindikizidwa omwe amagwiritsidwa ntchito ngati zinthu zoyambira pa mayesowa adaperekedwa ndi ALINVEST Břidličná, Czech Republic. Ali ndi aluminiyamu 98.11%, 1.3622% yachitsulo, 0.3618% ya manganese ndi zotsalira za mkuwa, magnesium, silicon, titaniyamu, zinki, chromium ndi nickel.
Zipangizo zomwe zasankhidwa popanga zinthu zophatikizika zimasankhidwa mogwirizana ndi mphamvu zawo za thermodynamic, zomwe zimatengera kuchuluka kwa madzi omwe angathe kuyamwa/kuchotsa kutentha pansi pa 120°C.
Magnesium sulfate (MgSO4) ndi imodzi mwa mchere wosangalatsa kwambiri komanso wophunziridwa bwino wa 30,31,32,33,34,35,36,37,38,39,40,41. Kapangidwe ka thermodynamic kayesedwa mwadongosolo ndipo kapezeka kuti ndi koyenera kugwiritsidwa ntchito m'magawo oziziritsira madzi, mapampu otentha komanso malo osungira mphamvu. Magnesium sulfate youma ya CAS-Nr.7487-88-9 99% (Grüssing GmbH, Filsum, Niedersachsen, Germany) idagwiritsidwa ntchito.
Calcium chloride (CaCl2) (H319) ndi mchere wina wophunziridwa bwino chifukwa hydrate yake ili ndi mphamvu zosangalatsa za thermodynamic41,42,43,44. Calcium chloride hexahydrate CAS-No. 7774-34-7 97% yogwiritsidwa ntchito (Grüssing, GmbH, Filsum, Niedersachsen, Germany).
Zinc sulfate (ZnSO4) (H3O2, H318, H410) ndi ma hydrate ake ali ndi mphamvu ya thermodynamic yoyenera njira zochepetsera kutentha45,46. Zinc sulfate heptahydrate CAS-Nr.7733-02-0 99.5% (Grüssing GmbH, Filsum, Niedersachsen, Germany) idagwiritsidwa ntchito.
Strontium chloride (SrCl2) (H318) ilinso ndi mphamvu zosangalatsa za thermodynamic4,45,47 ngakhale kuti nthawi zambiri imaphatikizidwa ndi ammonia mu kafukufuku wa adsorption heat pump kapena kusungira mphamvu. Strontium chloride hexahydrate CAS-Nr.10.476-85-4 99.0–102.0% (Sigma Aldrich, St. Louis, Missouri, USA) idagwiritsidwa ntchito popanga.
Copper sulfate (CuSO4) (H302, H315, H319, H410) si imodzi mwa ma hydrate omwe amapezeka kawirikawiri m'mabuku aukadaulo, ngakhale kuti mphamvu zake za thermodynamic ndizofunikira pakugwiritsa ntchito kutentha kochepa48,49. Copper sulfate CAS-Nr.7758-99-8 99% (Sigma Aldrich, St. Louis, MO, USA) idagwiritsidwa ntchito popanga.
Magnesium chloride (MgCl2) ndi imodzi mwa mchere wosungunuka womwe walandiridwa kwambiri posachedwapa pankhani yosungira mphamvu yotentha50,51. Magnesium chloride hexahydrate CAS-Nr.7791-18-6 pure pharmaceutical grade (Applichem GmbH., Darmstadt, Germany) idagwiritsidwa ntchito pa mayesowa.
Monga tafotokozera pamwambapa, hydroxyethyl cellulose idasankhidwa chifukwa cha zotsatira zabwino zomwe zimagwiritsidwa ntchito mofanana. Zinthu zomwe zimagwiritsidwa ntchito popanga ma hydroxyethyl cellulose CAS-Nr 9004-62-0 (Sigma Aldrich, St. Louis, MO, USA).
Ulusi wachitsulo umapangidwa ndi mawaya afupiafupi omangiriridwa pamodzi pogwiritsa ntchito compression ndi sintering, njira yotchedwa crucible melt extraction (CME)52. Izi zikutanthauza kuti kutentha kwawo kumadalira osati kokha pa kutentha kwa zitsulo zomwe zimagwiritsidwa ntchito popanga ndi porosity ya kapangidwe komaliza, komanso mtundu wa ma bond pakati pa ulusi. Ulusiwo si isotropic ndipo nthawi zambiri umagawidwa mbali ina panthawi yopanga, zomwe zimapangitsa kutentha kukhala kotsika kwambiri.
Kapangidwe ka madzi kamene kamayamwa madzi kanafufuzidwa pogwiritsa ntchito kusanthula kwa thermogravimetric nthawi imodzi (TGA)/kusanthula kwa thermogravimetric (DTG) mu phukusi la vacuum (Netzsch TG 209 F1 Libra). Kuyezaku kunachitika mumlengalenga wa nayitrogeni woyenda pamlingo wa 10 ml/min ndipo kutentha kumakhala pakati pa 25 mpaka 150°C mu zombo za aluminiyamu oxide. Kuchuluka kwa kutentha kunali 1 °C/min, kulemera kwa chitsanzo kunali kosiyana kuyambira 10 mpaka 20 mg, resolution inali 0.1 μg. Mu ntchitoyi, ziyenera kudziwika kuti kusiyana kwa unyinji pa unit pamwamba kuli ndi kusatsimikizika kwakukulu. Zitsanzo zomwe zimagwiritsidwa ntchito mu TGA-DTG ndi zazing'ono kwambiri komanso zodulidwa mosakhazikika, zomwe zimapangitsa kuti kudziwa kwawo malo kukhale kolakwika. Mitengo iyi ikhoza kungowonjezeredwa kudera lalikulu ngati kupotoka kwakukulu kuganiziridwa.
Ma spectra a Fourier transform infrared (ATR-FTIR) ochepetsedwa mphamvu adapezeka pa Bruker Vertex 80 v FTIR spectrometer (Bruker Optik GmbH, Leipzig, Germany) pogwiritsa ntchito chowonjezera cha ATR platinum (Bruker Optik GmbH, Germany). Ma spectra a makristalo a diamondi ouma okha adayesedwa mwachindunji mu vacuum asanagwiritse ntchito zitsanzozo ngati maziko a muyeso woyesera. Zitsanzozo zidayesedwa mu vacuum pogwiritsa ntchito spectral resolution ya 2 cm-1 ndi avareji ya ma scan a 32. Wavenumber imayambira pa 8000 mpaka 500 cm-1. Kusanthula kwa ma spectral kunachitika pogwiritsa ntchito pulogalamu ya OPUS.
Kusanthula kwa SEM kunachitika pogwiritsa ntchito DSM 982 Gemini kuchokera ku Zeiss pamagetsi othamanga a 2 ndi 5 kV. Kusanthula kwa mphamvu ya X-ray dispersive X-ray (EDX) kunachitika pogwiritsa ntchito Thermo Fischer System 7 ndi Peltier cooled silicon drift detector (SSD).
Kukonzekera mbale zachitsulo kunachitika motsatira njira yofanana ndi yomwe yafotokozedwa mu 53. Choyamba, ikani mbaleyo mu 50% sulfuric acid. Mphindi 15. Kenako anayikidwa mu 1 M sodium hydroxide solution kwa masekondi pafupifupi 10. Kenako zitsanzozo zinatsukidwa ndi madzi ambiri osungunuka, kenako n’kuziviika m’madzi osungunuka kwa mphindi 30. Pambuyo pokonza koyamba pamwamba, zitsanzozo zinamizidwa mu 3% saturated solution. HEC ndi target salt. Pomaliza, zichotseni ndi kuziumitsa pa 60°C.
Njira yopangira anodizing imawonjezera ndikulimbitsa gawo lachilengedwe la okosijeni pachitsulo chopanda ntchito. Mapanelo a aluminiyamu adadzozedwa ndi sulfuric acid atauma kenako n’kutsekedwa m’madzi otentha. Anodizing inatsatira kudulidwa koyamba ndi 1 mol/l NaOH (600 s) kutsatiridwa ndi kuchepetsedwa mu 1 mol/l HNO3 (60 s). Yankho la electrolyte ndi chisakanizo cha 2.3 M H2SO4, 0.01 M Al2(SO4)3, ndi 1 M MgSO4 + 7H2O. Anodizing inachitidwa pa (40 ± 1)°C, 30 mA/cm2 kwa masekondi 1200. Njira yotsekera inachitidwa m’njira zosiyanasiyana zamadzimadzi monga momwe tafotokozera m’zinthuzo (MgSO4, CaCl2, ZnSO4, SrCl2, CuSO4, MgCl2). Chitsanzocho chimaphikidwa mmenemo kwa masekondi 1800.
Njira zitatu zosiyana zopangira zinthu zopangidwa ndi zinthu zosiyanasiyana zafufuzidwa: chophimba cha guluu, kuchitapo kanthu mwachindunji, ndi kuchiza pamwamba. Ubwino ndi kuipa kwa njira iliyonse yophunzitsira kumasanthulidwa ndikukambidwa mwadongosolo. Kuyang'ana mwachindunji, kujambula zithunzi za nano, ndi kusanthula mankhwala/zinthu zinagwiritsidwa ntchito poyesa zotsatira zake.
Kuthira mafuta m'thupi (anodizing) kunasankhidwa ngati njira yosinthira pamwamba kuti kuwonjezere kumatirira kwa mchere. Kuthirira pamwamba kumeneku kumapanga kapangidwe ka mapokoso a alumina (alumina) mwachindunji pamwamba pa aluminiyamu. Mwachikhalidwe, njira iyi ili ndi magawo awiri: gawo loyamba limapanga kapangidwe ka mapokoso a aluminiyamu oxide, ndipo gawo lachiwiri limapanga chophimba cha aluminiyamu hydroxide chomwe chimatseka mapokoso. Njira ziwiri zotsatirazi ndi zotsekera mchere popanda kuletsa kulowa mu gawo la mpweya. Yoyamba imakhala ndi dongosolo la uchi pogwiritsa ntchito machubu ang'onoang'ono a aluminiyamu oxide (Al2O3) omwe amapezeka mu gawo loyamba kuti agwire makhiristo okhuta ndikuwonjezera kumatirira kwake pamwamba pa zitsulo. Mapokoso omwe amapezeka ali ndi mainchesi pafupifupi 50 nm ndi kutalika kwa 200 nm (Chithunzi 1a). Monga tanenera kale, maenje awa nthawi zambiri amatsekedwa mu gawo lachiwiri ndi wosanjikiza woonda wa Al2O(OH)2 boehmite wothandizidwa ndi njira yowira ya chubu cha alumina. Mu njira yachiwiri, njira yotsekera iyi imasinthidwa mwanjira yoti makhiristo amchere amagwidwa mu boehmite (Al2O(OH)), yomwe sigwiritsidwa ntchito potsekera pankhaniyi. Gawo lachiwiri limachitika mu yankho lodzaza la mchere wofanana. Mapangidwe omwe afotokozedwawa ali ndi kukula kwa 50–100 nm ndipo amawoneka ngati madontho otayidwa (Chithunzi 1b). Pamwamba pake pomwe pamapezeka njira yotsekera pali kapangidwe ka malo kodziwika bwino komwe kali ndi malo olumikizirana owonjezereka. Kapangidwe ka pamwamba aka, pamodzi ndi mawonekedwe awo ambiri omangirirana, ndiabwino kunyamula ndi kusunga makhiristo amchere. Mapangidwe onse awiri omwe afotokozedwawa amawoneka kuti ali ndi mabowo ndipo ali ndi mabowo ang'onoang'ono omwe amawoneka kuti ndi oyenera kusunga mchere ndi kutengera nthunzi ku mchere panthawi yogwira ntchito ya adsorber. Komabe, kusanthula kwa zinthuzi pogwiritsa ntchito EDX kumatha kuzindikira kuchuluka kwa magnesium ndi sulfure pamwamba pa boehmite, zomwe sizipezeka pakakhala pamwamba pa alumina.
ATR-FTIR ya chitsanzocho inatsimikizira kuti chinthucho chinali magnesium sulfate (onani Chithunzi 2b). Sipekitiramu ikuwonetsa ma ion a sulfate omwe ali ndi mawonekedwe pa 610–680 ndi 1080–1130 cm–1 ndi ma lattice water omwe ali ndi mawonekedwe pa 1600–1700 cm–1 ndi 3200–3800 cm–1 (onani Chithunzi 2a, c). ). Kupezeka kwa ma ion a magnesium sikusintha kwenikweni sipekitiramu54.
(a) EDX ya mbale ya aluminiyamu ya MgSO4 yokutidwa ndi boehmite, (b) ma spectra a ATR-FTIR a boehmite ndi MgSO4 zokutira, (c) ma spectra a ATR-FTIR a MgSO4 yoyera.
Kusunga mphamvu ya kulowetsedwa kwa madzi kunatsimikiziridwa ndi TGA. Pa chithunzi 3b chikuwonetsa nsonga ya kulowetsedwa kwa madzi pafupifupi 60°C. Nsonga iyi sikugwirizana ndi kutentha kwa nsonga ziwiri zomwe zawonedwa mu TGA ya mchere woyera (Chithunzi 3a). Kubwerezabwereza kwa kayendedwe ka kulowetsedwa kwa madzi kunayesedwa, ndipo kupotoka komweko kunawonedwa pambuyo poika zitsanzo mumlengalenga wonyowa (Chithunzi 3c). Kusiyana komwe kunawonedwa mu gawo lachiwiri la kulowetsedwa kwa madzi kungakhale chifukwa cha kuchepa kwa madzi mumlengalenga woyenda, chifukwa nthawi zambiri izi zimapangitsa kuti madzi asathe. Mitengo iyi ikufanana ndi pafupifupi 17.9 g/m2 mu kuchotsedwa koyamba kwa madzi ndi 10.3 g/m2 mu kuchotsedwa kachiwiri kwa madzi.
Kuyerekeza kwa kusanthula kwa TGA kwa boehmite ndi MgSO4: Kusanthula kwa TGA kwa MgSO4 yoyera (a), kusakaniza (b) ndi pambuyo pobwezeretsanso madzi m'thupi (c).
Njira yomweyi idachitika ndi calcium chloride ngati adsorbent. Zotsatira zake zaperekedwa mu Chithunzi 4. Kuyang'ana pamwamba pa chinthucho kwawonetsa kusintha pang'ono pa kuwala kwachitsulo. Ubweya wake sukuwoneka bwino. SEM idatsimikizira kukhalapo kwa makhiristo ang'onoang'ono omwe amagawidwa mofanana pamwamba pake. Komabe, TGA sinawonetse kutaya madzi m'thupi pansi pa 150°C. Izi zitha kukhala chifukwa chakuti gawo la mchere ndi laling'ono kwambiri poyerekeza ndi kulemera konse kwa gawo lapansi kuti TGA izindikire.
Zotsatira za kuchiza pamwamba pa copper sulfate coating pogwiritsa ntchito njira ya anodizing zawonetsedwa pa chithunzi 5. Pankhaniyi, kuphatikizidwa kwa CuSO4 komwe kumayembekezeredwa mu kapangidwe ka Al oxide sikunachitike. M'malo mwake, singano zotayirira zimawonedwa chifukwa zimagwiritsidwa ntchito kwambiri pa copper hydroxide Cu(OH)2 yomwe imagwiritsidwa ntchito ndi utoto wamba wa turquoise.
Chithandizo cha pamwamba pa anodized chinayesedwanso pamodzi ndi strontium chloride. Zotsatira zake zinasonyeza kufalikira kosagwirizana (onani Chithunzi 6a). Kuti adziwe ngati mchere unaphimba pamwamba ponse, kusanthula kwa EDX kunachitika. Kupindika kwa mfundo m'dera la imvi (mfundo 1 mu Chithunzi 6b) kukuwonetsa strontium yochepa komanso aluminiyamu yambiri. Izi zikusonyeza kuchuluka kochepa kwa strontium m'dera loyezedwa, zomwe zimasonyeza kuti strontium chloride ndi yochepa. Mosiyana ndi zimenezi, madera oyera ali ndi kuchuluka kwakukulu kwa strontium ndi aluminiyamu yochepa (mfundo 2-6 mu Chithunzi 6b). Kusanthula kwa EDX kwa dera loyera kukuwonetsa madontho akuda (mfundo 2 ndi 4 mu Chithunzi 6b), chlorine yochepa komanso sulfure yambiri. Izi zitha kusonyeza kupangika kwa strontium sulfate. Madontho owala kwambiri amasonyeza kuchuluka kwa chlorine ndi kuchuluka kochepa kwa sulfure (mfundo 3, 5, ndi 6 mu Chithunzi 6b). Izi zitha kufotokozedwa ndi mfundo yakuti gawo lalikulu la utoto woyera limapangidwa ndi strontium chloride yomwe ikuyembekezeka. TGA ya chitsanzocho inatsimikizira kutanthauzira kwa kusanthulako ndi nsonga pa kutentha kwapadera kwa strontium chloride yoyera (Chithunzi 6c). Mtengo wawo wochepa ukhoza kutsimikiziridwa ndi gawo laling'ono la mchere poyerekeza ndi kulemera kwa chithandizo chachitsulo. Kulemera kwa desorption komwe kunapezeka mu kuyesaku kukugwirizana ndi kuchuluka kwa 7.3 g/m2 komwe kwaperekedwa pa unit area ya adsorber pa kutentha kwa 150°C.
Zophimba za zinc sulfate zokonzedwa ndi Eloxal nazonso zinayesedwa. Pogwiritsa ntchito macroscopic, zophimbazo ndi zopyapyala kwambiri komanso zofanana (Chithunzi 7a). Komabe, SEM inavumbulutsa malo ophimbidwa ndi makristalo ang'onoang'ono olekanitsidwa ndi malo opanda kanthu (Chithunzi 7b). TGA ya zophimbazo ndi substrate inayerekezeredwa ndi ya mchere woyera (Chithunzi 7c). Mchere woyera uli ndi nsonga imodzi yosagwirizana pa 59.1°C. Aluminiyamu yokutidwayo inawonetsa nsonga ziwiri zazing'ono pa 55.5°C ndi 61.3°C, zomwe zikusonyeza kukhalapo kwa zinc sulfate hydrate. Kusiyana kwa kulemera komwe kunapezeka mu kuyeseraku kukufanana ndi 10.9 g/m2 pa kutentha kwa madzi okwanira 150°C.
Monga momwe zinalili kale53, hydroxyethyl cellulose idagwiritsidwa ntchito ngati chomangirira kuti ikonze kumatirira ndi kukhazikika kwa utoto wa sorbent. Kugwirizana kwa zinthu ndi momwe zimakhudzira magwiridwe antchito a adsorption kunayesedwa ndi TGA. Kusanthula kumachitika pokhudzana ndi kulemera konse, mwachitsanzo chitsanzocho chimaphatikizapo mbale yachitsulo yomwe imagwiritsidwa ntchito ngati substrate yophimba. Kumatirira kumayesedwa ndi mayeso kutengera mayeso a mtanda omwe afotokozedwa mu ISO2409 specification (sikukwaniritsa specification yolekanitsa utoto kutengera makulidwe ndi m'lifupi mwa specification).
Kupaka mapanelo ndi calcium chloride (CaCl2) (onani Chithunzi 8a) kunapangitsa kuti pakhale kugawa kosagwirizana, komwe sikunawonekere mu utoto woyera wa aluminiyamu womwe unagwiritsidwa ntchito poyesa kopingasa. Poyerekeza ndi zotsatira za CaCl2 yoyera, TGA (Chithunzi 8b) ikuwonetsa nsonga ziwiri zodziwika bwino zomwe zinasunthira kutentha kotsika kwa 40 ndi 20°C, motsatana. Kuyesa kwa cross-section sikulola kufananiza koyenera chifukwa chitsanzo choyera cha CaCl2 (chitsanzo kumanja mu Chithunzi 8c) ndi ufa wosalala, womwe umachotsa tinthu tapamwamba kwambiri. Zotsatira za HEC zinawonetsa utoto woonda kwambiri komanso wofanana wokhala ndi kumatira kokwanira. Kusiyana kwa kulemera komwe kwawonetsedwa mu chithunzi 8b kukugwirizana ndi 51.3 g/m2 pa unit adsorber pa kutentha kwa 150°C.
Zotsatira zabwino pankhani yomatira ndi kufanana zinapezekanso ndi magnesium sulfate (MgSO4) (onani Chithunzi 9). Kusanthula kwa njira yothira utoto kunawonetsa kukhalapo kwa nsonga imodzi ya pafupifupi 60°C. Kutentha kumeneku kukugwirizana ndi gawo lalikulu la kuthira utoto lomwe limawoneka pakuchepa kwa madzi m'mchere woyera, zomwe zikuyimira gawo lina pa 44°C. Kukugwirizana ndi kusintha kuchokera ku hexahydrate kupita ku pentahydrate ndipo sikuwonedwa pankhani ya zokutira ndi zomangira. Mayeso a mtanda akuwonetsa kufalikira bwino ndi kumamatira poyerekeza ndi zokutira zopangidwa pogwiritsa ntchito mchere woyera. Kusiyana kwa unyinji komwe kunawonedwa mu TGA-DTC kukugwirizana ndi 18.4 g/m2 pa unit dera la adsorber pa kutentha kwa 150°C.
Chifukwa cha kusakhazikika kwa pamwamba, strontium chloride (SrCl2) ili ndi utoto wosagwirizana pa zipsepse (Chithunzi 10a). Komabe, zotsatira za mayeso opingasa zinawonetsa kufalikira kofanana ndi kumamatira bwino kwambiri (Chithunzi 10c). Kusanthula kwa TGA kunawonetsa kusiyana kochepa kwambiri pakulemera, komwe kuyenera kukhala chifukwa cha kuchuluka kwa mchere wochepa poyerekeza ndi gawo lachitsulo. Komabe, masitepe omwe ali pa curve akuwonetsa kukhalapo kwa njira yochotsera madzi m'thupi, ngakhale kuti peak imagwirizanitsidwa ndi kutentha komwe kumapezeka pofotokoza mchere woyera. Ma peak pa 110°C ndi 70.2°C omwe adawonedwa mu Zithunzi 10b adapezekanso pofufuza mchere woyera. Komabe, gawo lalikulu la kusowa madzi m'thupi lomwe lidawonedwa mu mchere woyera pa 50°C silinawonekere mu ma curve pogwiritsa ntchito binder. Mosiyana ndi zimenezi, chisakanizo cha binder chinawonetsa ma peak awiri pa 20.2°C ndi 94.1°C, omwe sanayesedwe mchere woyera (Chithunzi 10b). Pa kutentha kwa 150 °C, kusiyana kwa kulemera komwe kumawonedwa kumafanana ndi 7.2 g/m2 pa unit area ya adsorber.
Kuphatikiza kwa HEC ndi zinc sulfate (ZnSO4) sikunapereke zotsatira zabwino (Chithunzi 11). Kusanthula kwa TGA kwa chitsulo chophimbidwa sikunawonetse njira iliyonse yochotsera madzi m'thupi. Ngakhale kufalikira ndi kumamatira kwa chophimbacho kwakula, makhalidwe ake akadali kutali kwambiri ndi abwino kwambiri.
Njira yosavuta yopaka ulusi wachitsulo ndi wosanjikiza woonda komanso wofanana ndi kulowetsedwa kwa madzi (Chithunzi 12a), komwe kumaphatikizapo kukonzekera mchere wofunikira ndi kulowetsedwa kwa ulusi wachitsulo ndi madzi.
Pokonzekera kulowetsedwa kwa madzi, mavuto awiri akuluakulu amakumana nawo. Kumbali imodzi, mphamvu ya pamwamba ya yankho la saline imalepheretsa kuti madziwo asalowe bwino mu kapangidwe kake kokhala ndi mabowo. Kupangika kwa makristalo pamwamba (Chithunzi 12d) ndi thovu la mpweya lomwe limatsekeredwa mkati mwa kapangidwe kake (Chithunzi 12c) kungachepetsedwe kokha pochepetsa mphamvu ya pamwamba ndikunyowetsa chitsanzocho ndi madzi osungunuka. Kusungunuka mokakamiza mu chitsanzo potulutsa mpweya mkati kapena popanga njira yothetsera vutoli mu kapangidwe kake ndi njira zina zothandiza zotsimikizira kuti kapangidwe kake kadzaza mokwanira.
Vuto lachiwiri lomwe linakumana nalo panthawi yokonzekera linali kuchotsa filimuyo kuchokera ku gawo la mchere (onani Chithunzi 12b). Chochitikachi chimadziwika ndi kupangidwa kwa chophimba chouma pamwamba pa kusungunuka, chomwe chimaletsa kuuma kolimbikitsidwa ndikuyamba njira yolimbikitsira kufalikira. Njira yachiwiri imakhala yocheperako kuposa yoyamba. Zotsatira zake, kutentha kwakukulu kumafunika kuti pakhale nthawi yoyenera youma, zomwe zimawonjezera chiopsezo cha thovu lopangika mkati mwa chitsanzo. Vutoli limathetsedwa poyambitsa njira ina yopangira makristalo yochokera osati pakusintha kwa kuchuluka (kutuluka kwa nthunzi), koma pakusintha kwa kutentha (monga momwe zilili ndi MgSO4 mu Chithunzi 13).
Kuwonetsera kwa njira yopangira makristalo panthawi yozizira komanso kulekanitsa magawo olimba ndi amadzimadzi pogwiritsa ntchito MgSO4.
Mayankho a mchere wokhuta amatha kukonzedwa kutentha kwa chipinda (HT) kapena kupitirira apo pogwiritsa ntchito njira iyi. Pachiyambi, kupangika kwa kristalo kunakakamizidwa pochepetsa kutentha komwe kuli pansi pa kutentha kwa chipinda. Pachiyambi chachiwiri, kupangika kwa kristalo kunachitika pamene chitsanzocho chinazizidwa kufika kutentha kwa chipinda (RT). Zotsatira zake ndi kusakaniza kwa makristalo (B) ndi kusungunuka (A), gawo lamadzimadzi lomwe limachotsedwa ndi mpweya wopanikizika. Njirayi sikuti imangopewa kupangika kwa filimu pa ma hydrate awa, komanso imachepetsa nthawi yofunikira pokonzekera zinthu zina zophatikizika. Komabe, kuchotsa madzi ndi mpweya wopanikizika kumabweretsa kupangika kwa mchere kwambiri, zomwe zimapangitsa kuti utotowo ukhale wokhuthala.
Njira ina yomwe ingagwiritsidwe ntchito kuphimba pamwamba pa chitsulo imaphatikizapo kupanga mwachindunji mchere wofunikira kudzera muzochita za mankhwala. Zosintha kutentha zophimbidwa zomwe zimapangidwa ndi momwe asidi amachitira pamwamba pa chitsulo cha zipsepse ndi machubu zili ndi zabwino zingapo, monga momwe tafotokozera mu kafukufuku wathu wakale. Kugwiritsa ntchito njira iyi pa ulusi kunapangitsa kuti pakhale zotsatira zoyipa kwambiri chifukwa cha kupangika kwa mpweya panthawi ya zoyeserera. Kupanikizika kwa mpweya wa haidrojeni kumasonkhana mkati mwa probe ndipo kumasuntha pamene chinthucho chikutulutsidwa (Chithunzi 14a).
Chophimbacho chasinthidwa kudzera mu reaction ya mankhwala kuti chiwongolere bwino makulidwe ndi kufalikira kwa chophimbacho. Njirayi imaphatikizapo kudutsa mtsinje wa asidi mu chitsanzo (Chithunzi 14b). Izi zikuyembekezeka kuti zipange chophimba chofanana ndi reaction ndi substrate metal. Zotsatira zake zinali zokhutiritsa, koma njirayi inali yochedwa kwambiri kuti ingaganizidwe ngati njira yothandiza (Chithunzi 14c). Nthawi yochepa yochitira zinthu ikhoza kupezeka ndi kutentha komweko.
Pofuna kuthana ndi zovuta za njira zomwe zili pamwambapa, njira yophikira pogwiritsa ntchito zomatira yaphunziridwa. HEC idasankhidwa kutengera zotsatira zomwe zaperekedwa m'gawo lapitalo. Zitsanzo zonse zidakonzedwa pa 3% wt. Chomangiracho chimasakanizidwa ndi mchere. Ulusiwo unakonzedwa kale motsatira njira yomweyi monga momwe zimakhalira ndi nthiti, mwachitsanzo kunyowa mu 50% vol. mkati mwa mphindi 15. sulfuric acid, kenako kunyowa mu sodium hydroxide kwa masekondi 20, kutsukidwa ndi madzi osungunuka ndipo pomaliza kunyowa m'madzi osungunuka kwa mphindi 30. Pankhaniyi, gawo lina linawonjezedwa musanalowetsedwe. Imani chitsanzocho kwakanthawi mu yankho la mchere wosungunuka ndikuwumitsa pa kutentha pafupifupi 60°C. Njirayi idapangidwa kuti isinthe pamwamba pa chitsulo, ndikupanga malo a nucleation omwe amathandizira kufalikira kwa chophimbacho mu gawo lomaliza. Kapangidwe ka ulusi kali ndi mbali imodzi pomwe ulusiwo ndi woonda komanso wokhuthala, ndi mbali inayo komwe ulusiwo ndi wokhuthala komanso wosafalikira kwambiri. Izi ndi zotsatira za njira 52 zopangira.
Zotsatira za calcium chloride (CaCl2) zafotokozedwa mwachidule ndi kufotokozedwa ndi zithunzi mu Gome 1. Kuphimba bwino pambuyo pobayira. Ngakhale zingwe zomwe sizinali ndi makhiristo owoneka pamwamba zinali ndi kuwunikira kochepa kwachitsulo, zomwe zikusonyeza kusintha kwa mapeto. Komabe, zitsanzo zitalowetsedwa ndi madzi osakaniza a CaCl2 ndi HEC ndikuumitsidwa pa kutentha kwa pafupifupi 60°C, zokutirazo zinakhazikika pamalo olumikizirana a zomangamanga. Izi zimachitika chifukwa cha kupsinjika kwa pamwamba pa yankho. Pambuyo ponyowa, madziwo amakhalabe mkati mwa chitsanzo chifukwa cha kupsinjika kwake pamwamba. Kwenikweni zimachitika pamalo olumikizirana a zomangamanga. Mbali yabwino kwambiri ya chitsanzocho ili ndi mabowo angapo odzazidwa ndi mchere. Kulemera kunawonjezeka ndi 0.06 g/cm3 pambuyo pobayira.
Kupaka ndi magnesium sulfate (MgSO4) kunapanga mchere wochuluka pa unit volume (Table 2). Pankhaniyi, kuchuluka komwe kunayesedwa ndi 0.09 g/cm3. Njira yobzala mbewu inapangitsa kuti chitsanzo chiphimbidwe kwambiri. Pambuyo pa njira yopaka, mchere umatseka madera akuluakulu a mbali yopyapyala ya chitsanzo. Kuphatikiza apo, madera ena a matte amatsekedwa, koma ma porosity ena amasungidwa. Pankhaniyi, kupanga mchere kumawonedwa mosavuta pamalo olumikizirana a nyumba, kutsimikizira kuti njira yopaka utoto imachitika makamaka chifukwa cha mphamvu ya pamwamba ya madzi, osati chifukwa cha kuyanjana pakati pa mchere ndi substrate yachitsulo.
Zotsatira za kuphatikiza kwa strontium chloride (SrCl2) ndi HEC zinawonetsa makhalidwe ofanana ndi zitsanzo zam'mbuyomu (Table 3). Pankhaniyi, mbali yopyapyala ya chitsanzo imakhala yophimbidwa pafupifupi yonse. Ma pores okha ndi omwe amaoneka, opangidwa panthawi youma chifukwa cha kutuluka kwa nthunzi kuchokera ku chitsanzo. Kapangidwe kamene kawonedwa mbali ya matte ndi kofanana kwambiri ndi ka m'mbuyomu, malowo amatsekedwa ndi mchere ndipo ulusi sunaphimbidwe kwathunthu.
Pofuna kuwunika zotsatira zabwino za kapangidwe ka ulusi pa kutentha kwa chosinthira kutentha, mphamvu yoyendetsera kutentha ya kapangidwe ka ulusi wophimbidwa idayesedwa ndikuyerekezeredwa ndi zinthu zoyera zophimbidwa. Mphamvu yoyendetsera kutentha idayesedwa malinga ndi ASTM D 5470-2017 pogwiritsa ntchito chipangizo cha flat panel chomwe chawonetsedwa pa Chithunzi 15a pogwiritsa ntchito chipangizo chofotokozera chomwe chimadziwika kuti ndi mphamvu yoyendetsera kutentha. Poyerekeza ndi njira zina zoyezera zosakhalitsa, mfundoyi ndi yothandiza pazinthu zokhala ndi mapokoso zomwe zimagwiritsidwa ntchito mu kafukufukuyu, popeza miyesoyo imachitika mokhazikika komanso ndi kukula kokwanira kwa chitsanzo (malo oyambira 30 × 30 mm2, kutalika pafupifupi 15 mm). Zitsanzo za zinthu zoyera zophimbidwa (zofotokozera) ndi kapangidwe ka ulusi wophimbidwa zidakonzedwa kuti ziyesedwe molunjika ku ulusi ndipo zimalunjika kulunjika kwa ulusi kuti ziwunikire momwe mphamvu yoyendetsera kutentha ya anisotropic imayendera. Zitsanzozo zidaphwanyidwa pamwamba (P320 grit) kuti zichepetse mphamvu yoyipa pamwamba chifukwa cha kukonzekera zitsanzo, zomwe sizikuwonetsa kapangidwe ka mkati mwa chitsanzocho.