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A continuous microreaction process was set up to analyze and improve the "green" synthesis of 5-hydroxymethylfurfural (5-HMF) based oil the HCl-catalyzed dehydration of fructose in pure aqueous solutions. The process conditions were deliberately shifted to high temperatures and pressures (185 degrees C, 17 bar) and combined with a reduced reaction time of only 1 min to avoid extensive rehydration of the product. 5-HMF was obtained with 75 % selectivity and 54 % yield at 71 % fructose conversion. In comparison to published data, a 24 % increase in selectivity and a 21 % increase in conversion could be achieved. Moreover, by adding organic co-solvents and extraction agents to the reaction system, both 5-HMF selectivity and yield could be further enhanced to 85 and 82 %, respectively. However, the use of additional organic solvents cannot be considered as a green process anymore

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The dramatic increase of atmospheric CO2 concentration is responsible for a fast and potentially unpredictable global climate change. Therefore, the implementation of negative carbon technologies such as direct air capture (DAC) is needed. Metal–organic frameworks (MOFs) have the potential to perform CO2 DAC and achieve unprecedented performances. Herein strategies to improve the CO2 capture efficiency of MOFs and their potential implementation in real applications are discussed. Three main categories of targeted modifications to the frameworks are usually performed to enhance the CO2 uptake capacity and adsorption selectivity: 1) modifications to the metal unit; 2) modifications to the linker unit; 3) confinement of solvents within MOFs. The synthesis of MOF composites using other porous materials as support is also a useful method to improve the CO2 capture performances. Another approach involves the synthesis of amine‐functionalized MOFs that can chemically bind carbon dioxide.