Valorization of orange industry residues to form a natural coagulant and adsorbent

Abstract The availability of by-products released as a result of the fruit processing development is a potential study area highlighting the possibility of valorizing them. This study presents an investigation on the valorization of orange juice factory pith and peel waste in terms of the recovering pectin and an adsorbent WT (Waste Treated). The recovered pectin was used in the removal of turbidity and the formed adsorbent was used for the removal of methylene blue (MB) and indigo carmine (IC) dyes. The pectin yield obtained under extraction conditions (pH 1.5, temperature 80–82 °C and extraction time 60 min) was found to be 16.32% and presenting moisture contain 10%, an ash contains 2.28 and an esterification degree of 65.21. With a dose of 6 mg/l, pectin used alone was able to reduce about 99% of initial turbidity at pH 3 after 30 min of settling time. For the waste recovered after the extraction of the pectin, an absorbance of 70.5% of the MB is obtained compared to 16.34% for IC which shows that our support is perfect to eliminate the cationic dye. Hence, N’GAOUS factory orange waste can be valorized in water treatment as a natural coagulant and adsorbent for water treatment with low environmental risks.