Studies Of Amines’ Fixation On Zinc Porphyrin For Carbon Dioxide Capture And Utilization

In the 21 st century,the rapid development of society accompanied with the huge consum ption of foss il fuels,s uch as coal,oil and nat ural ga s,which make the CO₂ content in the air increase.Ex ces sive CO₂ will not only underm ine t he living environm ent but also endanger human healt h.Therefore,the development of an effective CO₂ absorption and utilization method i s s ignificant.In this work,a new method of CO₂ capture and uti lizati on is proposed.Using the structural properties of metalloporphyrins,the volatile organi c amines were immobilized fi rst ly,and then the MTPP-amine s ys tem was used to capture C O₂.Final ly,the capture d CO₂ was used for the prepar ati on of alkaline earth carbonate.The specifi c operat ion was as fol lows:（1）Study on the recognition of six ki nds of transitional tetraphenyl metal porphyrin（MTPP）including MnTPP,FeTPP,CoTPP,NiTPP,CuTPP and ZnTPP,and six kinds of small gas molecul es,including C O₂,NO,CO,SO₂,N 2 and HCHO in flue gases.The results showed that the six kinds of MTPP had no effect on the identificati on of CO₂.CoTP P,NiTPP,C uTPP and ZnTPP could selectively identify the NO molecules by UV-vi s and fluorescence spectral techniques.（2）MTPP could not interact wit h CO₂,s o MTPP was used as a fixing agent for organic amines.The ex perimental results showed t hat FeTP P could immobi liz e ethylenediam ine and ethanolamine.CoTPP and ZnTPP can immobili ze ethyle nediamine,diethylamine,ethanolam ine,diet hanolamine and tri ethanolamine.（3）The MTPP-ami ne syst em was used for CO₂ capture.The result s s howed that FeTPP-ethyl enediamine,FeTP P-ethanolamine,ZnTPP-et hyl ene diamine,ZnTPP-diethylamine,ZnTPP-et hanolamine,ZnTPP-diethanolamine and ZnTPP-triethanolamine sys tem could be used for CO₂ capture.The interaction between ZnTPP and amines were studied by fluorescence spectrophotometer.ZnTP P could form a1: 1 complex with amine.The binding ability between amine and C O₂ was st ronge r than that between amine and ZnTPP.So ami ne i mmobiliz ed by ZnTPP coul d be taken away by the CO₂,and ami nes reacted wit h CO₂ to form ammoni um salts,so that ZnTPP is relea sed.（4）The captured CO₂ was used for the preparation of alkal ine ear th car bonate.Based on conditional control,smoot h spherical calcium carbonate,dumbbel l-shaped strontiumcarbonate and bar-sha ped barium car bonate were prepa red by static method and hydr othermal method.This process realized the new uti lizati on of CO₂.At the same t ime,ZnTPP and amine can be rec yc led during the experi ment.（5）Thus,this work presented a new typ e of green rec yc lable CC U method for captur e and utiliziation of CO₂ with ZnTPP as an amine fixi ng agent,as shown in the following figure.