Mesoporous Carbon from Optimized Date Stone Hydrochar by Catalytic Hydrothermal Carbonization Using Response Surface Methodology: Application to Dyes Adsorption

Providing efficient and environmental friendly ways to recover lignocellulosic waste remains a challenge around the world. In this study, citric acid-catalyzed hydrothermal carbonization (CHTC) was coupled with pyrolysis convert date seed (Ds) into adsorbent material. regard, central composite design (CCD) using response surface methodology (RSM) developed examine influence of temperature, reaction time, catalyst dose on mass yield (Ym(%)) carbon retention rate (CRR(%)) in produced hydrochars. The optimized hydrochar (OHC-Ds) obtained under optimal conditions (200°C, 120 min, 20 mg) characterized by Ym(%) CRR(%) 59.71% 75.84%, respectively. Chemical activation KOH OHC-Ds followed at 600°C resulted an active material (AOHC-Ds) rich high specific area 1251.5 m2/g, dominance mesopores, as well amorphous structure comparable graphite shown X-ray diffraction (XRD) analysis. Adsorption experiments two dyes AOHC-Ds showed maximum adsorption capacity (Qm) 657.89 mg g−1 for methylene blue (MB) 384.61 methyl orange (MO) compared other conventional adsorbents. This result is due low acidity (pHpzc) AOHC-Ds, which equals 6.75, its surface, also oxygenated functional groups such (-OH), (C=O), (C-O) FTIR These results suggest that coupling CHTC encouraging way prepare inexpensive remove wastewater.