Pollution caused by heavy metals, due to their toxicity and harmful effects on plant species, is considered one of the fundamental problems. The unique properties of graphene oxide (GO) in adsorbing heavy metals from contaminated soil systems have garnered attention in the past decade. This study evaluates the effects of different doses of graphene oxide (0.5 and 1.5 g kg-1) on the adsorption and distribution of heavy metals, including Cadmium (Cd) and Copper (Cu) fractions, in soil contaminated with two rates (2% and 10%) of sewage sludge (SS) over a 92-day period. Subsamples were collected from the soils at intervals of 5, 15, 29, 57, and 92 days, air-dried, and subjected to metal fractionation. The aim was to evaluate the separation of Cd and Cu by employing a five-stage sequential extraction technique, where each stage involved 2 grams of air-dried soil as a sample. The overall metal quantity in the treatments was determined by utilizing aqua regia digestion. The recovery rate was determined by calculating the percentage of the total metal concentration obtained from acid digestion, involving the summation of the concentrations of the five metal fractions. The results showed that the F1 fraction of heavy metals in the soil with a 2% SS rate decreased with an increase in GO dosage. The calculated mobility factor of the metals at five incubation times (5, 15, 29, 57, and 92 days) was found to be in the range of 28.1-60.9 for Cd and 14.4-25.3 for Cu, indicating a higher mobility of Cd. The findings suggest that the presence of GO as an adsorbent and the incubation time were critical parameters in stabilizing heavy metals in the soil with different rates of SS. Additionally, the nature of the applied SS was found to influence the fractionation of heavy metals in the soil, besides providing elements. پرونده مقاله