Biosorbents prepared from orange peels using Instant Controlled Pressure Drop for Cu(II) and phenol removal

•Orange peel can be used as a biosorbent for phenol and Cu(II) uptake.•DIC process modifies the orange peel structure and chemical surface.•A chemical treatment increases adsorption capacity and selectivity for pollutants

In the present study Instant Controlled Pressure Drop (DIC) process, a vacuum drying technology, followed by chemical treatment of surfaces, was evaluated as an alternative in the preparation of biosorbents. The results show that DIC treatment modifies the structure of the peels and the number of active sites. Subsequent chemical treatment led to changes in the ratio between acidic and basic sites for adsorption of phenol and Cu(II) as model compounds. Adsorption studies showed that the biosorbent prepared using DIC and subsequent chemical modification increases the phenol adsorption capacity from 2.24 to 32.51 mg g−1. In the case of Cu(II), increments from 31.79 to 106.91 mg g−1 were observed.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slide