Nikolova М.Pencheva M.Dimov M.Bozadzhiev B.Lazarov L.Damyanova S.Lasheva V.Stoyanova A.Yavorov N.2024-07-162024-07-162024-07-162024-07-162023-01-011314-79781314-7471SCOPUS_ID:85152134192https://rlib.uctm.edu/handle/123456789/1422During the processing of fennel fruits (Foeniculum vulgare Mill.) for obtaining essential and vegetable oils, biomass is released. It is mainly used as an additive for feeding or as an organic fertilizer. The aim of this research is to investigate the possibilities of using biomass obtained during the processing of fruits from harvest 2020 and 2021 as a biosorbent of Cr (VI) from aqueous solutions or as a biofuel. The two biomasses were milled and the final fractions obtained by sieve analysis (between 384 and 413 μm) were analyzed. The FTIR spectrum was recorded as 4000 - 400 с-1. Both biomasses act as biosorbent under the following conditions: pH 1.0, agitation speed 300 rpm, adsorbent dose 1.05 g L-1, initial Cr (VI) concentration 80 mg L-1, temperature 30°C. The energy indices used in the assessment of fennel fruit biomass potential as conditional biofuel were calculated: calorific value (15783.40 - 15968.16 kJ kg-1), density (464.19 - 582.91 kg m-3), and heat equivalent (250.05 - 317.68 kJ m-3)enArticle