De Castro Douglas, Alberto RochaAlberto RochaDe Castro DouglasRibeiro, Haroldo Jorge da SilvaHaroldo Jorge da SilvaRibeiroHamoy Guerreiro, Lauro HenriqueLauro HenriqueHamoy GuerreiroDa Costa Assunção, Fernanda PaulaFernanda PaulaDa Costa AssunçãoPinto Bernar, LucasLucasPinto BernarSilva, Nilton Pereira daNilton Pereira daSilvaMuniz D’Antona Guimarães, DanielaDanielaMuniz D’Antona GuimarãesMonteiro, Marta ChagasMarta ChagasMonteiroPizarro Borges, Luiz EduardoLuiz EduardoPizarro BorgesKuchta, KerstinKerstinKuchtaTeixeira Machado, NelioNelioTeixeira MachadoDuvoisin Jr. Sergio2026-05-272026-05-272026-05-21Catalysts 16 (5): 485 (2026)https://hdl.handle.net/11420/63218This study aims to systematically investigate the combined effect of chemical activation of a&ccedil;a&iacute; seeds (<i>Euterpe oleracea</i> Mart.), with an aqueous sodium hydroxide (NaOH) solution at 2 mol&middot;L<sup>&minus;1</sup>, and process temperature by pyrolysis of alkaline activated a&ccedil;a&iacute; seeds on the yield of reaction products (bio-oil, gas, H<sub>2</sub>O, and biochar), physicochemical properties (acid value, density, and kinematic viscosity) and chemical composition (hydrocarbons and oxygenates) of bio-oil. Catalytic pyrolysis was carried out in a 143 L reactor at temperatures of 350 &deg;C, 400 &deg;C, and 450 &deg;C, 1.0 atmosphere, operating in batch mode. The NaOH activation played a crucial role in modifying the thermal degradation pathway of the biomass, promoting the formation of specific chemical structures and altering the product yields. NaOH acted as a catalyst, enhancing the deoxygenation of the biomass and stimulating the formation of hydrocarbons. As a result, the yields of bio-oil, water, biochar, and gas varied from 5.77 to 7.20% (by mass), 14.90 to 19.77% (by mass), 41 to 54% (by mass), and 25.33 to 32.03%, respectively, influenced by the increase in temperature. FT-IR analyses indicated the presence of characteristic chemical functions of hydrocarbons (alkanes, alkenes, and aromatics) and oxygenated compounds (phenols, cresols, ketones, esters, carboxylic acids, aldehydes, and furans), with an intensification of hydrocarbon signals at higher temperatures. GC-MS analysis identified hydrocarbons and oxygenated compounds as the main chemical classes in the bio-oil, showing a strong dependence on pyrolysis temperature. It was observed that hydrocarbon concentration in bio-oil increased from 49.7% to 57.88% (area) with increasing temperature, while the concentration of oxygenated compounds decreased from 13.88% to 6.69% (area), demonstrating that NaOH activation, combined with temperature elevation, favors the formation of hydrocarbons and the reduction of oxygenated compounds, thereby improving the quality of the produced bio-oil.en2073-4344Catalysts2026Multidisciplinary Digital Publishing Institutehttps://creativecommons.org/licenses/by/4.0/Technology::660: Chemistry; Chemical EngineeringCatalytic pyrolysis of Açaí (Euterpe oleracea Mart.) seeds: circular economy for agro-industrial waste-to-energy in the AmazonJournal Article2026-05-26https://doi.org/10.15480/882.1719710.3390/catal1605048510.15480/882.17197