In this paper, it is given a literature review of the research, which shows that the separation of chitin and its modification into chitosan is important for use in various fields as a biopolymer that supports the sustainable development. The results of the modification of chitosan with collagen have shown that its specific surface area significantly increase, which is extremely important for use in adsorption processes. [31]. Furthermore, it is given an example from the literature, the application of chitosan in the process of waste water treatment contaminated by drugs. The work [34], was investigated the modification of rubber particles with chitosan in order to increase the efficiency of the waste water treatment process by the adsorption process. The results showed that it is necessary to modify rubber particles with lower chitosan concentration, approximately 25%, because then, they have the highest adsorption capacity. As well, the results showed that too much chitosan concentration causes aggregation of rubber particles resulting in reduce of adsorption. This paper also investigated the influence of medium acidity on the adsorption process and the results showed that the favorable range is from slightly acidic to slightly alkaline. However, from the point of view of environment and from the aspect of process costs, a neutral waste water treatment medium is the most appreciated one.