# Application of Potato Peels as an Unconventional Sorbent for the Removal of Anionic and Cationic Dyes from Aqueous Solutions

## TL;DR

This study explores using potato peels to remove various dyes from water, showing their effectiveness as a natural sorbent.

## Contribution

The novelty lies in evaluating potato peels as a low-cost sorbent for both anionic and cationic dyes under varying pH conditions.

## Key findings

- Potato peels showed highest sorption efficiency for dyes at specific pH levels.
- Maximum sorption capacities varied between 10.28 mg/g and 27.15 mg/g for different dyes.
- Sorption equilibrium times ranged from 45 to 270 minutes depending on dye type and concentration.

## Abstract

The aim of this study was to investigate the sorption efficiency of anionic dyes—Reactive Yellow 84 (RY84) and Reactive Black 5 (RB5)—and cationic dyes—Red 46 (BR46) and Basic Violet 10 (BV10)—onto potato peels (Solanum tuberosum L.). The research scope included characterization of the sorbent material (pHPZC, FTIR), the effect of pH on dye sorption efficiency, kinetics (pseudo-first-order and pseudo-second-order models, intraparticle diffusion model), and studies on the sorbent’s maximum sorption capacity (Langmuir 1 and 2, and Freundlich isotherms). The point of zero charge (pHPZC) for potato peels was determined to be pHPZC = 6.43, indicating a slightly acidic character of the material. The sorption efficiency for RB5, RY84, and BV10 was highest at pH 2, while the efficiency for BR46 was highest at pH 6. The time required to reach sorption equilibrium on the tested sorbent increased with the initial dye concentration and ranged from 180 to 270 min for RB5, RY84, and BV10, and from 45 to 210 min for BR46. The maximum sorption capacity of this material was found to be 20.85 ± 0.33 mg/g and 21.63 ± 0.34 mg/g for RB5 and RY84, respectively, and 10.28 ± 0.24 mg/g and 27.15 ± 0.87 mg/g for BV10 and BR46, respectively.