Nur Farahizzati Binti Zainun, , creator author. text my 2025 2025 monographic eng 79 pages : illustrations ; Lignin, a major by-product of the pulp and paper industry, holds significant potential for various industrial applications. However, current lignin recovery methods are often inefficient, leading to resource wastage and environmental challenges. The objective of this research is to evaluate the effectiveness of acidification with and without ultrasound-assisted treatment for lignin recovery from pulp and paper wastewater. The methodology involves treating paper waste samples with sulfuric acid under controlled conditions, with one set of samples subjected to ultrasound-assisted treatment. The recovered lignin is characterized using analytical techniques such as FTIR, UV spectroscopy, and TGA to assess its properties. The results indicate that combining acidification with ultrasound-assisted treatment significantly enhances lignin recovery rates compared to acidification alone. significant improvements when ultrasound was applied, particularly when the time was extended to 70 minutes. The ultrasound-assisted method resulted in higher lignin yield compared to the acidification method, with the purity further increasing as sonication power was raised from 300 W to 500 W. Additionally, lignin recovered with ultrasound treatment exhibits improved structural and thermal properties. In conclusion, this study presents an efficient and sustainable approach to lignin extraction from pulp and paper waste, contributing to resource optimization and environmental conservation in the industry. Lignin extraction via the use of an ultrasound-assisted extraction method holds a very significant and industrial perspective value. specialized Nur Farahizzati Binti Zainun Faculty of Chemical and Process Engineering Technology Final Year Report (Bachelor of Chemical Engineering ) -- Universiti Malaysia Pahang Al-Sultan Abdullah - 2025 Include bibliographical reference Faculty of Chemical and Process Engineering Technology Dissertations Universities and colleges Dissertations Theses Dissertations THE0010697 (Local) UMPSA 260709 20260709174936.0 eng