The applying of carbon as an adsorbent is a widely known technique of elimination of chemical pollution, together with dyes, from waste waters. Nevertheless, lots of consideration is now being paid to bettering the adsorbent effectivity and looking for low cost precursors for activated carbon (AC) manufacturing. On this work, AC is obtained from flax shive by its bodily and chemical activation with KOH. The pyrolysis course of and mechanism of KOH activation are studied utilizing thermogravimetric evaluation. The strategies of X-ray diffraction, energy-dispersive X-ray spectroscopy, scanning electron microscopy, and low-temperature nitrogen adsorption are used to find out the AC traits. The AC capacity to adsorb the methylene blue (MB) dye is studied. The impact of the properties of the synthesized AC on the MB equilibrium adsorption capability is analyzed. The utmost BET floor space of the AC is the same as 1832.2 m2/g, which suggests its values lie within the vary typical of business activated carbons. The utmost equilibrium adsorption capability of MB is 464.2 mg/g. The AC adsorption capability relies on the cellulose content material within the flax shive and pore dimension distribution over the carbon matrix. Using lignocellulosic biomass, specifically flax shive, within the AC manufacturing is related to fixing environmental issues, similar to agricultural waste recycling and disposal.