Utilization of Biochar from Date Palm for Wastewater Treatment Technologies: Mini-Review

Recently, recycling agricultural waste has gained great importance in the field of the biochar industry, as it is a sustainable and inexpensive material that can be used to get rid of environmentally polluting materials. Dates are one of the major agricultural wastes in Iraq and the Gulf countries, which include fronds, seeds, and trunks. The challenge of obtaining a green and clean environment is represented by the safe disposal of these residues. These wastes are promising materials for producing biochar products as efficient adsorbents with improved characteristic properties. The present article revises the synthesis of biochar derived from date palm as an adsorbent for various types of pollutants, with a brief discussion about the chemical structure, properties, and adsorption mechanism of date palm biochar for the removal of different contaminants. Also, it highlights the engineering biochar modified by various techniques such as acid–alkaline modified biochar, magnetic biochar, and metal-non-metal biochar. The review also explored the adsorption performance from the perspective of isotherm and kinetic models supported by qualified studies, highlighting the main mechanisms such as π–π interaction, electrostatic attraction, and hydrogen bonding. The current work collects the scientific research that has been published about the importance of date balm as biochar in Iraq and the Arab Gulf, unlike previous studies that have focused on general feedstocks. The review recognizes the lack of standardized pyrolysis protocols, limited reusability studies, and insufficient information about the deep characteristics of biochar chemistry. Finally, future perspectives are outlined on scaling up biochar production, optimizing reactor design, and integrating biochar with other renewable technologies to achieve energy-efficient, low-emission, and sustainable wastewater treatment systems.