Abstract
This paper investigates and compares various methods for determining residual lignin in industrial hemp. Lignin is a complex polymer that is one of the main components of plant cell walls, which gives rigidity and strength to the plant structure. For industrial hemp, which is used in the industry for the production of paper, fabrics and other products, it is important to control the residual lignin content, since its excess can affect the quality of the final product and processing processes. When determining residual lignin, the influence of various factors such as time, bath module and temperature is assessed, and a regression equation is determined. The study experimentally compares several methods for determining residual lignin using acid and alkali to remove primary lignin, including 72% sulfuric acid and 2% hydrochloric acid. The obtained data are presented in a tabular state, analyzed, graphs are made for full and single-factor regression. The main objective of this work is to identify the most accurate, reliable and effective method for determining residual lignin in industrial hemp, which can be used in industry for quality control and optimization of production processes. The results of the study can be useful for enterprises engaged in hemp processing, as well as for scientific laboratories studying the properties of industrial plants.