In the present study, the ability for novel carbon microspheres (CMs) derived from date palm (Phoenix dactylifera) biomass using a hydrothermal carbonization (HTC) process and activated using phosphoric acid to remove methylene blue dye was investigated. Three types of palm-based wastes (seeds, leaflet, and inedible crystallized date palm molasses) were used and converted to CMs via the HTC process. The prepared samples were then activated using phosphoric acid via the incipient wetness impregnation method. The CMs samples before and after activation were analyzed using scanning electron microscopy (SEM), elemental analysis and scanning (CHNS), and the Fourier transform infrared (FTIR) and Brunauer–Emmet–Teller (BET) methods. The samples exhibited high BET surface areas after activation (1584 m²/g). The methylene blue adsorption results showed good fitting to the Langmuir, Fruendlich, and Temkin isotherm models for all activated samples. The maximum adsorption capacity achieved was 409.84 mg/g for activated CM obtained from the palm date molasses, indicating its high potential for application as a dye-based adsorption material.

The removal of lead metals from wastewater was carried out with carbon microspheres (CMs) prepared from date palm leaflets using a hydrothermal carbonization process (HTC). The prepared CMs were subsequently activated with phosphoric acid using the incipient wetness impregnation method. The prepared sample had a low Brunauer–Emmet–Teller (BET) surface area of 2.21 m²·g⁻¹, which increased substantially to 808 m²·g⁻¹ after the activation process. Various characterization techniques, such as scanning electron microscopy, BET analysis, Fourier transform infrared, and elemental analysis (CHNS), were used to evaluate the morphological structure and physico-chemical properties of the CMs before and after activation. The increase in surface area is an indicator of the activation process, which enhances the absorption properties of the material. The results demonstrated that the activated CMs had a notable adsorption capacity, with a maximum adsorption capacity of 136 mg·g⁻¹ for lead (II) ions. This finding suggests that the activated CMs are highly effective in removing lead pollutants from water. This research underscores the promise of utilizing activated carbon materials extracted from palm leaflets as an eco-friendly method with high potential for water purification, specifically in eliminating heavy metal pollutants, particularly lead (II), contributing to sustainability through biomass reuse.

In this work, carbon microspheres (CMs) were prepared by hydrothermal carbonization (HTC) of inedible crystallized date palm molasses. The effects of temperature and reaction time on the prepared materials were studied. Experiments were carried out at different temperatures (180, 200, 230 and 250 °C) with reaction times ranging from 2 to 10 h. It was found that temperature had the greatest influence on the mass yield of the CMs. No solid products were observed at a temperature of 180 °C and a reaction time less than 2 h. The highest yield was found to be 40.4% at 250 °C and a reaction time of 6 h. The results show that the CMs produced were approximately 5–9 μm in diameter. The results also show that the largest diameter of the CMs (8.9 μm) was obtained at a temperature of 250 °C and a reaction time of 6 h. Nonetheless, if the reaction time was extended beyond 6 h at 250 °C, the CMs fused and their shapes were deformed (non-spherical shapes). The synthesized materials were characterized using Scanning Electron Microscopy (SEM), Fourier Transform Infrared (FTIR), Branuer-Emmett-Teller (BET) and thermogravimetric analysis (TGA). BET surface areas for the four samples were found to be less than 1 m²/g. The methylene blue adsorption studies indicated that the equilibrium adsorption capacity was reached after 15 min, with a maximum adsorption capacity of 12 mg/g. The recycling of date palm molasses (a known processed waste) to generate a useable carbon microsphere represents a beneficial step in the application of sustainable processing industries in the Middle East.

In the present study, the ability of novel carbon microspheres (CMs) derived from a date palm (Phoenix dactylifera) biomass using a hydrothermal carbonization (HTC) process and activated using phosphoric acid in removing methylene blue dye was investigated. Three types of palm-based wastes (seeds, leaflet and inedible crystallized date palm molasses) were used and converted to CMs via HTC process. The prepared samples were then activated using phosphoric acid via incipient wetness impregnation method. The CMs samples before and after activation were analyzed using scanning electron microscopy (SEM), elemental analysis and scanning (CHNS), Fourier Transform-Infrared (FTIR) and Brunauer–Emmet–Teller (BET) method. The samples exhibited high BET surface areas after activation (1,584 m2/g). The methylene blue adsorption results showed good fittings to the Langmuir and Redlich-Peterson isotherm models for all activated samples. The maximum adsorption capacity achieved was 409.84 mg/g for activated CM obtained from the palm date molasses, indicating high potential for application as dye-based adsorption materials.