AbstractWheat straw (an agricultural by-product) was pulped by an alkaline anthraquinone (AQ) process. Then the straw pulp was treated by high-power ultrasound under different noble-gas (argon, krypton, xenon) combinations. The pulps’ degree of beating and acid-insoluble lignin content were measured. Handsheets were made from sonicated and control pulps and tested for paper tensile strength. In this study we explore which noble-gas combination with ultrasound may be more useable to reduce the lignin content and enhance fibrillation. We also describe the most effective ultrasound-assisted, modified alkaline pulping process. Overall, we found that in two steps ultrasonification decreased the residual lignin contents more then 75 %, the pulp fibrillation increased from 12 to 70 °SR within 20 min. of ultrasound irradiation, and the tensile index of the handsheets increased by 65%. For sustainable paper production, it is required to develop alternative paper resources. Paper made from alternate fiber resources with efficient technology will improve our living standards without sacrificing the environment, our habitat. High frequency ultrasound-based pulp processing offers significant improvements, and it reduces energy and chemical consumptions for pulp and paper production.