In the current study, parthenium hysterophorus-derived biochars (PTCs) were used as low-cost and environment-friendly sorbents in batch mode and fixed-bed columns to assess the adsorption behavior of tartrazine dye (TTZ) by varying operational settings and analyzing mathematical models. In the batch adsorption study, the Langmuir and pseudo-first-order models provided the best expression for TTZ adsorption onto PTCs with an uptake capacity of 95.57 mg/g at maximum. In the fixed bed column, the sorption of TTZ was promoted with greater bed height, reduced flow velocity, and higher dye concentration. Comparing the column models (Yoon-Nelson, Thomas, and Clark), the Clark model provided the best fit with the experimental data and effectively represented the adsorption process. The accompanying experimental data agreed with the breakthrough curves. The maximum adsorption capacity achieved with the column process was 8.32 mg/g. In contrast to other adsorbents, PTCs showed excellent adsorption efficiency and a strong potential for reusability.