Pyrolysis of lemon peel waste in a fixed-bed reactor and characterization of innovative pyrolytic products

Abstract

The pyrolysis of LPW was carried out in a laboratory fixed-bed reactor at final temperature of 300°C, 400°C and 500°C with an incremental heating rate of 10°C/min, under N2 atmosphere. The maximum yields of bio-oil, biochar and gas were 16.66 wt.% (at 400°C), 66.89 wt.% (300°C) and 54.6 wt.% (500°C), respectively. The recovered biochar FTIR characterization reveals that it is a promising precursor to produce carbon materials, biofertilizer and for solid fuel applications. The bio-oil chemical characterization (GC-MS and FTIR analyzes) shows its richness with innovative compounds such as squalene, d-limonene, ß-Sitosterol and phenol, suitable for applications agriculture, biochemical and pharmaceutical industries. The pyrolytic oil presents also good properties, suitable for its use as an engine fuel or as a potential source for synthetic fuels. The recovered pyrolytic gas has a maximum calorific value around 12 MJ/kg with an average composition of CO (up to 75.87 vol.%), of CH4 (up to 5.25 vol.%) and of CnHm (up to 1.48 vol.%). The results could be applied by citrus 2 farmers and agri-food industrials for large scale application to ensure a sustainable waste management of their citrus by-products and to guarantee economic benefits.

Citrus limetta fruit waste management by liquefaction using hydrogen-donor solvent

“…Both the biomasses had HHV values that were in close conformity with other lignocellulosic biomasses 5,53 and fruit wastes. 2,42,51 The ultimate analysis of CLPU showed 43.16 wt% of elemental carbon composition, which was comparable to 38.51 wt% of similar citrus biomass waste. 51 The hydrogen content was also in range with other lignocellulosic biomasses.…”

“…The H/C ratio of CLPU and CLPE was 1.568 and 1.772, respectively, and was consistent with similar fruit waste biomasses. 2,42,51 However, the O/C ratio of 0.855 and 0.873 for CLPU and CLPE, respectively, was slightly lower compared to other similar biomass, 42,51 which added value to CLPU and CLPE for utilizing them as a source for the production of biocrude.…”

“…In both the biomasses, the ash content was almost similar to other fruit wastes (pomace and peels). 42,51,52 The FC content of CLPU was less than 10.5 wt%, indicating that the biochar yield was less than that of biocrude. Both the biomasses had HHV values that were in close conformity with other lignocellulosic biomasses 5,53 and fruit wastes.…”

“…Both CLPU and CLPE had high VM content of 61.33 wt% and 66.35 wt%, respectively, which was actually an affirmative indication from the biocrude yield point of view as biomasses with high VM get devolatilized easily along with the production of less amount of char. 42 The amount of inorganic compounds present in the biomass was detected by its ash content. In both the biomasses, the ash content was almost similar to other fruit wastes (pomace and peels).…”

“…Besides, the biochar obtained from these peels has also been used as an adsorbent for the removal of lead from battery manufacturing industrial effluent. 39 Biodiesel production from CL seed oil by simple transesterification process 40 and pyrolysis of such citrus fruits 41,42 has paved the path for their utilization in other thermochemical conversion processes. Moreover, none of these studies deal with the liquefaction and extensive product analysis of CL fruit waste.…”