Carbonatation

Carbonatation
Bayanai
Ƙaramin ɓangare na	chemical reaction (en) da carbonation reaction (en)
Defining formula (en)	$\mathrm {Ca(OH)_{2}+CO_{2}\to CaCO_{3}+H_{2}O}$

Carbonatation wani sinadarin sinadarai ne wanda Calcium hydroxide ke amsawa tare da carbon dioxide kuma yana samar da calcium carbonate mai narkewa:

${\ce {Ca(OH)2{+}CO2->CaCO3{+}H_2O}}$

Tsarin samar da carbonate wani lokacin ana kiransa "carbonation", kodayake wannan kalmar yawanci tana nufin tsarin narkewar carbon dioxide a cikin ruwa.

Kyakkyawan ƙira

Carbonatation ya haifar da lalatawar rebar

Carbonatation tsari ne mai jinkiri wanda ke faruwa a cikin lime" data-linkid="16" href="./Concrete" id="mwGQ" rel="mw:WikiLink" title="Concrete">kankare inda lemun tsami (CaO, ko Ca (OH) _{2 (aq)} ) a cikin siminti ke amsawa tare da carbon dioxide (CO2) daga iska kuma yana samar da calcium carbonate.

Ruwa a cikin pores na Ciminti na Portland yawanci alkaline ne tare da pH a cikin kewayon 12.5 zuwa 13.5. Wannan yanayin alkaline mai yawa shine wanda aka rufe katako na ƙarfe kuma an kare shi daga lalata. Dangane da zane-zane na Pourbaix don baƙin ƙarfe, ƙarfe ba ya wucewa lokacin da pH ya fi 9.5.

Carbon dioxide a cikin iska yana amsawa tare da alkali a cikin siminti kuma yana sa ruwa ya fi acidic, don haka rage pH. Carbon dioxide zai fara carbonatate siminti a cikin siminti daga lokacin da aka yi abu. Wannan tsarin carbonatation zai fara a farfajiyar, sannan sannu a hankali yana motsawa zurfi da zurfi a cikin kankare. Adadin carbonatation ya dogara da yanayin zafi na kankare - 50% na zafi na dangi ya fi dacewa. Idan abu ya fashe, carbon dioxide a cikin iska zai fi dacewa ya shiga cikin kankare.

A ƙarshe wannan na iya haifar da lalatawar rebar da lalacewar tsari ko gazawar.

Tsabtace sukari

Ana amfani da tsarin carbonatation a cikin samar da sukari daga sukari. Ya haɗa da gabatar da limewater (madara na lime - dakatarwar na calcium hydroxide) da iskar gas mai wadataccen carbon dioxide a cikin "ya'yan itace" (mai wadataccen sukari da aka shirya daga matakin watsawa na tsari) don samar da calcium carbonate da kuma zubar da ƙazantawa wanda aka cire. Dukan tsari yana faruwa a cikin "tanki na carbonatation" kuma lokacin sarrafawa ya bambanta daga minti 20 zuwa awa ɗaya.

Carbonatation ya ƙunshi waɗannan tasirin:

• Karin alkalinity yana rufe sunadarai a cikin ruwan 'ya'yan itace.
• Calcium carbonate yana shan kayan ado
• Alkalinity yana lalata wasu sukari na monosaccharide, galibi glucose da fructose

Manufar babban abu ne wanda ke daidaitawa da sauri don barin ruwan 'ya'yan itace. Ruwan a ƙarshen kusan 15 ° Bx ne da 90% sucrose. pH na ruwan 'ya'yan itace da aka samar shine ma'auni tsakanin cire calcium da yawa daga mafita da kuma sa ran pH ya sauka a fadin aiki daga baya. Idan ruwan 'ya'yan itace ya zama acidic a cikin matakan crystallisation to sucrose da sauri ya rushe zuwa glucose da fructose; ba wai kawai glucose da Fructose suna shafar crystalllization ba amma suna 'molassagenic' suna shan adadin sucrose zuwa matakin molasses.

Gas din carbon dioxide ya kumbura ta hanyar cakuda ya samar da calcium carbonate. Ana haɗa abubuwa marasa sukari a cikin ƙwayoyin carbonate na calcium kuma an cire su ta hanyar halitta (ko taimako) a cikin tankuna ko masu tsabta.

Akwai tsarin carbonatation da yawa, waɗanda aka ba su suna daga kamfanonin da suka fara kirkirar su. Sun bambanta da yadda aka gabatar da lemun tsami, zafin jiki da tsawon kowane mataki, da kuma rabuwa da abubuwa masu ƙarfi daga ruwa.

• Dorr (kuma Dorr-Oliver) - ci gaba da aiki ta amfani da tankuna biyu tare da sake amfani ("1st carbonatation") don gina girman ƙwayoyin don flocculation na halitta. Adadin sake amfani shine kusan 7:1. Ana rarraba barbashi a ƙarƙashin nauyi a cikin wani mataki mai kauri a cikin mai bayyanawa. Ana ƙara ruwan 'ya'yan itace a cikin wani tanki ("2nd carbonatation") kuma a tace shi. Ana tace laka mai maida hankali (ƙasa) daga mai tsabtacewa kuma / ko matse don dawo da ƙarin ruwa. Tsarin Dorr yana da ƙarancin kulawa da ƙarfin mutum amma yana iya fuskantar matsalolin tacewa lokacin da aka sarrafa beets da suka lalace. An fi son shi a Burtaniya da Amurka.
• DDS (Det Danske Sukkerfabrik - "The Danish Sugarfactory") - tsari mai yawa wanda ya shafi pre-liming inda pH na ruwan 'ya'yan itace ke karuwa a hankali don fara hazo na sunadarai, sannan ta kara karin lime da CO₂ gas. Ana cire barbashi a kowane mataki ta hanyar tacewa.
• RT (Raffinerie Tirlemontoise - "Sugar refinery of Tienen") - wani tsari mai yawa tare da matakin farko. Hakanan an cire barbashi ta hanyar tacewa.

Dukkanin hanyoyin DDS da RT suna da kyau daga masana'antun Turai. Tsarin carbonatation gabaɗaya ya dace da Tsarin watsawa; ruwan 'ya'yan itace daga masu watsa shirye-shiryen RT ana sarrafa su ta hanyar RT carbonatation.

Ruwan da ke fitowa daga carbonatation an san shi da "ruwan ruwan 'ya'yan itace". yana iya fuskantar gyare-gyaren pH tare soda ash na soda da ƙari na sulfur ("sulfitation") kafin mataki na gaba wanda shine maida hankali ta hanyar tasirin tasirin da yawa.

Rashin taushi na ruwa

Halin carbonatation yana faruwa ne yayin taushiyar lemun tsami (tsarin Clark) a cikin taushiyar ruwa.

Dubi kuma

• Alkali–silica reaction
• Concrete degradation
• Phosphatation — a similar process used in sugarcane processing.