Açaí (Euterpe oleracea), a popular Amazonian fruit, is vital to Pará's economy, producing 90% of Brazil's açaí. However, its processing generates significant waste, causing environmental concerns. This study focuses on using açaí seed waste to develop bioflocculants and activated carbon (AC) for water treatment. Bioflocculant was produced from tannin-rich açaí seed extract via the Mannich reaction, combining 58 g of ammonium chloride, 220 mL of formaldehyde, and 28 mL of hydrochloric acid, heated for 30 minutes at 80°C with continuous stirring at 300 RPM. After obtaining 198 mL of tannin extract (36.86 mg/mL) by decoction at 100°C for 4 hours, the extract was added to the solution, stirred for 8 hours at 65°C, and subsequently lyophilized. Activated carbon was made from the filtered extract residue, chemically activated with sodium hydroxide (1:3 g/g) and calcined at 400°C for 3 hours in the absence of oxygen. Seven tests were conducted to assess the efficacy of the products, with the optimal result achieved using 0.0187 g of bioflocculant for 200 mL of raw water, followed by filtration with 60.7 g of AC. Turbidity was measured by the nephelometric method, and pH was assessed with a pH meter, both in triplicate. According to Brazilian regulations, the acceptable limits for drinking water are 40 NTU for turbidity and a pH between 6.0 and 9.0. Results showed a marked reduction in turbidity, from 195.3 NTU in untreated water to 2.02 NTU after bioflocculant treatment and 0.93 NTU after additional filtration with activated carbon. The pH improved from 5.0 in untreated and flocculated water to 7.0 after filtration with AC. These findings demonstrate the potential of repurposing açaí waste for sustainable water purification, offering an eco-friendly solution to both environmental and water treatment challenges.