A novel pressed coal from citrus and cooking oil wastes using fungi

Mohamed S Hasanin; Amr H Hashem; Hassan M Abu Hashish; Mohamed Abdelraof

doi:10.1186/s40643-022-00582-8

A novel pressed coal from citrus and cooking oil wastes using fungi

Bioresour Bioprocess. 2022 Sep 5;9(1):95. doi: 10.1186/s40643-022-00582-8.

Authors

Mohamed S Hasanin¹, Amr H Hashem², Hassan M Abu Hashish³, Mohamed Abdelraof⁴

Affiliations

¹ Cellulose & Paper Department, National Research Centre, 33 El Bohouth St., Dokki, P.O. 12622, Giza, Egypt.
² Botany and Microbiology Department, Faculty of Science, Al-Azhar University, Cairo, 11884, Egypt. amr.hosny86@zhar.edu.eg.
³ Mechanical Engineering Department, Engineering Research Division, National Research Centre, Giza, Egypt.
⁴ Microbial Chemistry Department, National Research Centre, Dokki, Cairo, 12622, Egypt. abdelraof87@gmail.com.

Abstract

Nowadays renewable energy with low prices is a global target that has taken the attention to compare alternatives energy sources with fossil fuels. Therefore, this study was established to find suitable and sustainable alternative low-cost fuels source. Cooking oil waste (COW) was mixed with non-pretreated citrus tree fibers (CTF) (0.5 mL to 1 g ratio) and pressed to formulate coal (CTF/COW). Otherwise, this mixture was subjected to in situ fungal pretreated using Aspergillus flavus isolate to simplify the mixture composition and pressed to offer in a usable form with enhancing their heating value for the first time. CTF/COW was characterized using attenuated total reflection Fourier-transform infrared spectroscopy (ATR-FTIR), scanning electron microscope (SEM) and thermal analysis (TGA) before and after treatment. The fungal isolate was observed with enzyme productivity and activity of CMCase, avicelase, xylanase, mannanase, α-glucosidase, β-glucosidase, lignin peroxidase and lipase according to enzyme assays and the chemical compositions of CTF before and after fungal treatment, where the best PH for enzymes extraction was between 5 and 7. The fungal enzymes increased the heating value by about two and half folds in comparison with non-pretreated coal. Moreover, the calorific value of tCTF/COW was 43,422 kJ/kg, which was higher than CTF recorded 18,214 kJ/kg and COW recorded 39,823 kJ/kg. Our result suggests that fungal treatment of the mixture of citrus trees and cooking oil waste presents as a promising low-cost and eco-friendly coal.

Keywords: Aspergillus flavus; Citrus trees fibers; Cooking oil waste; Fuels; Screw press.