Optimized synthesis of nano-scale high quality HKUST-1 under mild conditions and its application in CO2 capture

Xueliang Mu,Yipei Chen,Edward Lester,Tao Wu

doi:10.1016/j.micromeso.2018.05.027

Xueliang Mu, Yipei Chen + Show 2 more

Open Access

https://doi.org/10.1016/j.micromeso.2018.05.027

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Abstract

This study was focused on the development of an optimized method for the rapid synthesis of nano-scale HKUST-1 with high yield, high surface area and high CO2 uptake capacity but under mild conditions. A series of HKUST-1 were synthesized under different conditions, such as preparation time, temperature, activation method, etc. It was found that the nano-scale HKUST-1 MOFs (T85-3-Pm4-120) was successfully synthesized at a high yield (87%) under low temperature (85 °C) using a mixture of Triethylamine (TEA), Cu2+ and trimesic acid (TMA) with a molar ratio of 6:3:2. The highest porosity was achieved via this pristine HKUST-1 being activated (powder activation, drying at 120 °C) four times using methanol to remove impurities trapped in the pores. The best HKUST-1 MOFs (T85-3-Pm4-120) hereby prepared was then tested in CO2 adsorption and exhibited an adsorption capacity of 2.5 mmol/g. It is therefore demonstrated that the new approach proposed in this study is a rapid and effective way to synthesize highly porous HKUST-1 MOFs under mild conditions, which is of comparable surface area and CO2 uptake capacity with those MOFs prepared under harsh conditions.

Highlights

Metal–organic frameworks (MOFs) are hybrid crystalline compounds consisting of organic ligands bridging inorganic moieties
The first attempt was made to find out an optimal reaction duration and temperature for the synthesis of MOFs
The results showed that the CO2 desorption process finished rapidly during N2 purging under the same conditions and the CO2 adsorption capacity remains almost unchanged after ten adsorption/desorption cycles, which demonstrated the good adsorption stability of T85-3-Pm4

Summary

Introduction

Metal–organic frameworks (MOFs) are hybrid crystalline compounds consisting of organic ligands bridging inorganic moieties. MOFs exhibit unique structure and outstanding properties in porosity, pore size and surface area and have been used in various fields such as gas storage, adsorption, separation, and catalysis[1]. More and more effort has been made to explore the application of nano-scale MOFs in areas, such as liquid phase catalysis[2,3], adsorption[4] and drug delivery[5], etc. The conventional solvothermal method for the preparation of HKUST-1 involves heating the solution up to 180 °C to form crystalline Cu3. The Cu3 (BTC)[2], synthesized at 75–120 °C, has to be kept in an autoclave for a long period, varying from 1 day up to a few weeks, to remove impurities that are trapped in the pores 8

Methods

Results

Conclusion