Preparation and Properties of A Hyperbranch-Structured Polyamine adsorbent for Carbon Dioxide Capture

Abstract

A fibrous adsorbent with amino-terminated hyperbranch structure (PP-AM-HBP-NH2) was prepared by grafting hyperbranched polyamine (HBP-NH2) onto the acrylamide-modified polypropylene (PP) fibers. The grafting of AM on PP fibers provided the active sites for introducing HBP-NH2 onto the PP fibers. This kind of “grafting to” procedure to synthesize hyperbranch-structured fiber could overcome the disadvantages of stepwise growth procedure, avoiding the complicated synthesis process and the requirement of strict experimental conditions. The grafted HBP-NH2 was three-dimensional dentritic architecture and had a large number of pores existing within the grafted polymers, which is favorable for CO2 molecules to diffuse into the HBP-NH2. Therefore, the as-prepared PP-AM-HBP-NH2 fibers showed a high adsorption capacity (5.64 mmol/g) for CO2 in the presence of water at 25 °C, and the utilization efficiency of alkyl amino groups could reach 88.2%, demonstrating that the hyperbranched structure of adsorbents can greatly promote adsorption capacity and efficiency. This could be attributed to better swelling properties and lower mass transfer resistance to CO2 of the hyperbranched adsorbent. PP-AM-HBP-NH2 also showed excellent regeneration performance, and it could maintain the same adsorption capacity for CO2 after 15 recycle numbers as the fresh adsorbent.

The application of amine-based materials for carbon capture and utilisation: an overarching view

“…121 Hyperbranched polyamine grafted acrylamide-modified polypropylene fibres had a high adsorption capacity of 5.64 mmol CO 2 per g at 25 1C in 10% CO 2 /N 2 due to low mass transfer resistance after swelling in water. 99 Similarly, while dry PEI hydrogel beads adsorbed negligible amounts of CO 2 under 15% CO 2 /N 2 at ambient temperature, they adsorbed 1.37 mmol g À1 CO 2 when soaked to 70 wt% water content due to better amine accessibility via the water filled pores. 27 Glycerol has also been shown to act as a plasticiser; when incorporated into the structure of PAI/silica/PEI hollow fibre adsorbents, breakthrough CO 2 capacity was improved by 60%.…”

“…98 An amine-functionalised nanofibrilated cellulose sorbent has been prepared by adding N-(2-aminoethyl)-3-aminopropylmethyldimethoxysilane to a cellulose hydrogel, 33 and acrylamide modified polypropylene fibres have been grafted with hyperbranched polyamines synthesised from the reaction between pentaethylenehexamine (PEHA) and methyl acrylate. 99 In an innovative approach to utilising polyamines in a CO 2 physisorbent, PEHA and tetraethylenepentamine (TEPA) and have acted as templating reagents in the synthesis of an inorganic gallium phosphite framework featuring 18membered-ring channels. 100 3.2.3 Unsupported polyamine adsorbents.…”

“…120 Water has also been shown to have a beneficial effect on CO 2 adsorption capacity and kinetic uptake, to a greater or lesser extent, in many studies in which a polyamine adsorbent is exposed to moisture prior to and/or during adsorption. 27,94,99,108,116 Water may promote adsorption in several ways. Firstly, in the presence of water, the theoretical overall amine efficiency is improved as one mole of CO 2 can react with one mole of amine to form one mole of ammonium bicarbonate, Fig.…”

The impact of pyrolysis conditions on orange peel biochar physicochemical properties for sandy soil

“…Similarly, the O1s peak was deconvoluted into four components (He et al, 2017;Hu et al, 2019). It was observed that the C-C/ C-H and C=C content increased from 77.0% to 82.0% as the pyrolysis temperature increased from 300°C to 600°C, which indicates an increase in the degree of biochar carbonization and aromatization.…”

Green synthesis of nitrogen-doped self-assembled porous carbon-metal oxide composite towards energy and environmental applications

“…Consequently, multilayer formation of CO 2 gas at the pores of the nanocomposite might have occurred. Further, it can be seen that adsorption capacity decreases with increasing temperature 33 . This can be due to the increase in kinetic energy with the increase in temperature that helps the gas molecules to desorb faster from the surface active sites and pores.…”