当前位置: X-MOL 学术J. Taiwan Inst. Chem. E. › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
Kinetic and thermodynamic study of CO2 storage in reversible gellan gum supported dry water clathrates
Journal of the Taiwan Institute of Chemical Engineers ( IF 5.5 ) Pub Date : 2020-10-17 , DOI: 10.1016/j.jtice.2020.09.034
Fatemeh Golkhou , Ali Haghtalab

The effects of "Dry Gel" on the carbon dioxide hydrate formation and storage capacity were studied. Gel-supported dry water (Dry Gel) was prepared by mixing gelling agents, hydrophobic silica nanoparticles, water, and air in a high-speed blender. The kinetic parameters of carbon dioxide hydrate formation such as mole of consumed gas, induction time, gas uptake rate, storage capacity, final conversion of water to hydrate, and apparent rate constant were investigated in the presence of dry gel with different gel strength (0 to 15 wt.%) at two silica ratios (5 and 10 wt.%). The experiments of hydrate formation were performed using a 200 cc stainless-steel vessel with and without stirring under the initial condition of 21 bars and 15 °C. Meanwhile, the thermodynamic recyclability of both dry water and dry gels over multiple hydrate cycles were studied. Besides, we utilized the diffusion-reaction kinetics model of Englezos and Bishnoi for calculating the apparent rate constant of hydrate growth. The van der Waals-platteeuw model, through a reversed micelle approach, was used to obtain hydrate phase equilibrium conditions. Results revealed that the amount of gas uptake increased significantly in both dry water and dry gel systems compared to pure water. It was found that dry gel with 15 wt.% gellan gum could substantially improve the storage and recyclability of CO2 hydrate by decreasing the decay percent from 68.8 to 5.1 over repeating seven hydrate cycles.

Moreover, the more Nano-silica content, the better the storage repeatability was observed. It was also shown that the equilibrium hydrate formation conditions were approximately stable in the presence of dry gels. Mixing seemed to be critical for multiple freezing-thawing hydrate cycles since it could reduce the reaction and induction time significantly. Finally, the dry water and dry gel can be used as a promising platform for carbon dioxide capturing using clathrate through the recyclability of hydrate formation.



中文翻译:

可逆结冷胶支持的干燥水包合物中CO 2储存的动力学和热力学研究

研究了“干凝胶”对二氧化碳水合物形成和储存能力的影响。通过在高速搅拌机中混合胶凝剂,疏水性二氧化硅纳米颗粒,水和空气来制备凝胶支撑的干水(干凝胶)。研究了在存在不同凝胶强度(0两种二氧化硅比例(5和10 wt。%)的重量百分比至15 wt。%)。水合物形成的实验是使用200 cc不锈钢容器在21 bar和15°C的初始条件下进行或不进行搅拌而进行的。与此同时,研究了干水和干凝胶在多个水合物循环中的热力学可循环性。此外,我们利用Englezos和Bishnoi的扩散反应动力学模型来计算水合物生长的表观速率常数。通过逆胶束方法的范德华斯-普拉特夫模型被用来获得水合物相平衡条件。结果表明,与纯水相比,干水和干凝胶系统中的气体吸收量均显着增加。发现具有15重量%的吉兰糖胶的干凝胶可以显着改善CO的储存和可回收性。用于获得水合物相平衡条件。结果表明,与纯水相比,干水和干凝胶系统中的气体吸收量均显着增加。发现具有15重量%的吉兰糖胶的干凝胶可以显着改善CO的储存和可回收性。用于获得水合物相平衡条件。结果表明,与纯水相比,干水和干凝胶系统中的气体吸收量均显着增加。发现具有15重量%的吉兰糖胶的干凝胶可以显着改善CO的储存和可回收性。2水合物通过在重复7个水合物周期减小从68.8衰变%至5.1。

此外,纳米二氧化硅含量越高,观察到的存储重复性越好。还显示出在存在干凝胶的情况下,平衡水合物的形成条件是大致稳定的。混合似乎对于多个冻融水合物循环至关重要,因为它可以显着减少反应和诱导时间。最后,干水和干凝胶可以用作有前途的平台,利用包合物通过水合物形成的可回收性来捕获二氧化碳。

更新日期:2020-11-22
down
wechat
bug