PROPERTIES OF SORBENTS FROM PINE BARK ACTIVATED BY MECHANOCHEMICAL METHODS

Abstract

The influence of pine bark pre-activation conditions: 1) in a planetary mill AGO-2, 2) with water vapor under the conditions of explosive autohydrolysis (EAH), on the sorption activity of resulting sorbents with respect to methylene blue and gelatin was studied. It is shown that explosive autohydrolysis is a more efficient method to activate pine bark, and under certain conditions it leads to an increase in the sorption of methylene blue and gelatin at least by a factor of 1.8 and 3.8, respectively, compared with the sorbent from non-activated bark. The activating treatment of pine bark in a planetary mill makes it possible to increase the sorption of methylene blue and gelatin not more than by a factor of 1.3 and 1.2, respectively. A mathematical model is obtained that describes the effect of explosive autohydrolysis conditions (water vapour pressure and duration of pine bark treatment) on the sorption properties of the resulting sorbents. Optimal conditions providing the maximal sorption of methylene blue by the obtained sorbent are determined: temperature 155 °C; water vapour pressure 2.62 MPa; processing time 58.6 s. The sorption properties of the sorbent predicted by the mathematical model have been confirmed experimentally. Sorbents from pine bark, activated by explosive autohydrolysis, surpass the industrial enterosorbent Polifepan from hydrolytic lignin in their ability to absorb methylene blue and gelatin, which indicates the prospects for their use as enterosorbents in medicine and veterinary medicine. The results of the conducted research allow us to consider pine bark as an alternative raw material that can replace hydrolytic lignin in the production of effective enterosorbents.