Abstract: To bolster national energy security and promote clean, efficient coal valorization, direct coal liquefaction? has emerged as a fundamental industrial route. However, this process is invariably accompanied by the generating large amount of coal liquefaction residue and high-concentration, recalcitrant liquefaction wastewater. While fractional extraction has enabled the utilization of coal liquefaction residue, the remaining large quantity of solid residue (raffinate slag) after extraction still lacks effective utilization means. Adhering to the " waste-treats-waste" philosophy, this study proposed to use the raffinate slag as raw material to prepare hierarchical porous adsorbents via KOH activation, and employe them to remove organic pollutants and ammonia nitrogen in the pretreatment stage of liquefaction wastewater. The pore structure, phase composition, surface morphology and chemical properties of the adsorbents were systematically characterized by a series of fine characterization methods such as N2 adsorption, XRD, SEM-EDS, FT-IR and XPS. Results indicated that the adsorbent synthesized under optimal conditions (750 °C for 2 h、mass ratio 1:1) achieved removal efficiencies of 76.6% for COD and 27.05% for ammonia nitrogen. Furthermore, surface modification via Cu loading significantly enhanced these efficiencies to 80.3% and 50.78%. FT-IR and XPS analyses revealed a synergistic physical-chemical adsorption mechanism, primarily driven by micropore filling, intermolecular hydrogen bonding, π-π interactions, and coordination complexation. This study provides a feasible technical route for the synergistic treatment and resource valorization of coal liquefaction raffinate slag and liquefaction wastewater.