Efficient Removal of Siloxane from Biogas by Using β-Cyclodextrin-Modified Reduced Graphene Oxide Aerogels

In this study,β-cyclodextrin-modified reduced graphene oxide aerogels (β-CD-rGOAs) were synthesized via a one-step hydrothermal method and were used to remove hexamethyldisiloxane (L2) from biogas. Theβ-CD-rGOAs were characterized by the Brunner–Emmet–Teller technique, using Fourier-transform infrared spectroscopy, Raman spectrometry, scanning electron microscopy (SEM), contact angle measurements, and X-ray diffraction. The results of the characterizations indicate thatβ-CD was grafted onto the surface of rGOAs as a cross-linking modifier. Theβ-CD-rGOA had a three-dimensional, cross-linked porous structure. The maximum breakthrough adsorption capacity of L2 onβ-CD-rGOA at 273 K was 111.8 mg g−1. A low inlet concentration and bed temperature facilitated the adsorption of L2. Moreover, theβ-CD-rGOA was regenerated by annealing at 80 °C, which renders this a promising material for removing L2 from biogas.Keywords:reduced graphene oxide aerogel;β-cyclodextrin;hydrothermal reduction;hexamethyldisiloxane;contaminant removal