智慧型奈米鈣-鋁水滑石材料應用於CO2 捕捉與CO2/H2分離膜之研發

Abstract

為了人類過度消耗石化燃料與不斷的釋放二氧化碳，造成地球溫度上升，已經成為高度關心的議題，使有關二氧化碳捕捉與處理的科技研究已經吸引世界各地高度關注。為了滿足這個挑戰，本研究計畫主要是針對未來在整合氣化複合式循環(Integrated Gasification Combined Cycle (IGCC)電場的使用下的中高溫環境二氧化碳捕捉的固態吸附劑和CO2/H2 的分離膜。主要研究計畫內容分為兩部分: (1)發展高效率中高溫CO2 吸脫附之高比表面積中孔洞鈣摻雜層狀水滑石(Ca-based LDH)粉體的最佳製程，並且研究其對於二氧化碳吸脫附行為與相關的動力學。同時經由製程調控及元素的改變來研發在不同中高溫下的CO2 吸脫附形為及多次循環劣化機制。(2)透過中孔洞層狀結構材料的研發，利用在中高溫環境下CaOCaCO3的碳化過程，藉由動力學來調控CaO表層的增長，進而微調微孔洞的呎吋大小來製備中高溫CO2/H2 的無機分離厚膜。探討不同複合陶瓷結構膜，於中高溫環境下，對二氧化碳和氫氣的吸附與分離效率之影響。並研究在不同組成及不同溫度下，H2及CO2於此氧化物膜中之擴散作用與其晶體組成之關係，了解其於實際操作環境中之長期穩定性和可能遭遇之問題， 同時透過此層狀結構材料的結構再記憶及再生的研究，來解決此材料經高溫多次循環使用劣化的問題，以期發展成可再利用及控制的智慧分離膜。

Excessive consumption of fossil fuels and irresponsible emission of CO2 into atmosphere has lead to rising ambient temperature that has caused significant concerns over sustainability of mankind. To address this challenge, this project provides a cohesive strategy to carbon capture and reuse at mid-to-high temperature via employment of novel mesoporous solid absorbers and separation membrane of CO2/H2. Two major research works will be performed in this project.(1) We intend to carry out synthesis and structural characterization for mesoporous Ca-doped layer double hydrates (Ca-Al LDH), and study its CO2 sorption behavior and related kinetics in mesoporous Ca-based LDH powder at mid-high temperature range. (2) We intend to develop the inorganic oxide membrane for CO2/H2 separation through the carbonization of CaO to CaCO3 to control and tune the nanopore size by investigating the kinetics. To identify the optimized membrane which has high efficiency to separate hydrogen from H2/CO2 mixed gases, and apply it into hydrogen purification at medium-high temperature. The adsorption-diffusion reactions of hydrogen/carbon-dioxide on membrane surface and relationship between diffusion behavior and the crystal composite will be studied to optimize its composite and enhance its application potential.