异氟尔酮二胺-水二元固-液相变吸收剂捕集CO_(2)机制  

Mechanism of CO_(2)capture into isophorone diamine-water binarysolid-liquid biphasic absorbent

作　　者：龙青海 王琛 龚娟娟 程思艺 吕碧洪[1] 周作明[1] 荆国华[1] LONG Qinghai;WANG Chen;GONG Juanjuan;CHENG Siyi;LYU Bihong;ZHOU Zuoming;JING Guohua(Xiamen Key Laboratory of Terrigenous Environmental Pollution Treatment and Ecological Remediation,Department of Chemistry,Huaqiao University,Xiamen 361021,China)

机构地区：[1]华侨大学化工学院,厦门市陆源环境污染治理与生态修复重点实验室,福建厦门361021

出　　处：《能源环境保护》2024年第3期91-99,共9页Energy Environmental Protection

基　　金：国家自然科学基金资助项目(22278168,22276064)。

摘　　要：固-液相变吸收剂在CO_(2)负荷调控下可发生相变形成固体产物,具有易分离、操作简便的优势,但现有体系大多需有机分相剂调控才能发生固液相变,存在分相剂易挥发损耗、富液黏度大等瓶颈。本研究构建了异氟尔酮二胺(IPDA)-水二元固-液相变吸收体系,无需分相剂,水相溶液吸收CO_(2)后即可发生固液相变。研究表明,1.00 mol·L^(-1)IPDA水溶液在313.15 K下饱和吸收负荷高达0.85 mol CO_(2)·mol^(-1),吸收产物为白色晶体粉末且富集在溶液下层,富液体积占总溶液体积的43.60%,而CO_(2)富集率达93.98%,此时,上层贫相黏度为1.08 mPa·s。富相固体产物分离熔融后在393.15 K温度条件下解吸60 min,再生效率为98.31%。经5次循环吸收-解吸,再生容量仍保持初始容量的80%以上,具有良好的重复利用性。^(13)C核磁共振(NMR)表征分析表明,IPDA与CO_(2)反应生成IPDA-氨基甲酸盐与碳酸氢盐,大多聚集在富相中,仅少量氨基甲酸盐溶于贫相中。解吸完成后,样品未见CO_(2)产物峰,进一步证明了IPDA-H_(2)O可完全解吸。量子化学计算证明,吸收前IPDA与水偶极矩接近,极性相近可互溶,吸收后形成的产物偶极矩低、极性小,产物间的分子内氢键高于产物和水的氢键,产物晶格能增加。因此,产物从溶液中析出,无需分相剂调控,即可在水中发生固液相变。Solid-liquid biphasic absorbents offer the advantages of easy separation and operation due to the formation of a solid phase after CO_(2)capture,which can be separated by static precipitation.However,most existing absorbents require organic phase separators to regulate phase transition,leading to issues including volatile loss of phase separators and high viscosity of the rich liquid phase.In this study,a novel amine-water binary solid-liquid biphasic absorbent was developed.This absorbent exhibits solid-liquid phase change behavior without the need for an organic phase separator after CO_(2)absorption in the aqueous solution.Absorption experiments showed that the total absorption capacity of IPDA-H_(2)O could reach 0.85 mol CO_(2)·mol^(-1)at a concentration of 1.00 mol·L^(-1)and an absorption temperature of 313.15 K.After reaching saturation,CO_(2)was concentrated in the lower solid phase,which accounted for 43.60%of the total solution volume and contained 93.98%of the total absorption loading.The CO_(2)-lean phase had a low viscosity of 1.08 mPa·s.After being hot-melted,the solid products were regenerated at 393.15 K for 60 min,with a regeneration efficiency of 98.31%.Even after 5 absorption and desorption cycles,the regeneration capacity remained above 80%of its initial capacity,indicating good regeneration stability.13 C NMR spectra showed that most of the IPDA-carbamate and its decomposition product,bicarbonate,were concentrated in the rich solid phase,while a small amount of unprecipitated carbamate and water were present in the lean phase.^(13)C NMR spectra indicated that CO_(2)was almost completely released from IPDA-H_(2)O,demonstrating the system′s excellent absorption-desorption performance.Quantum chemical calculations revealed that IPDA and H_(2)O had similar dipole moments before CO_(2)absorption,indicating similar polarity and high mutual solubility.After absorption,the dipole moment of the products decreased.Additionally,the intramolecular hydrogen bonding within the products was found to be

关 键 词：碳捕集 固-液相变吸收剂 有机胺 吸收-解吸性能 反应机理 

分 类 号：X51[环境科学与工程—环境工程] X701