Experimental determination of the effects of pretreatment on selected Nigerian lignocellulosic biomass in bioethanol production

Abstract

In the present study, five lignocellulosic biomass namely, corn cobs (Zea mays), rice husks (Oryza sativa), cassava peels (Manihot esculenta), sugar cane bagasse (Saccharum officinarum), and white yam peels (Dioscorea rotundata) of two mesh sizes of 300 and 425 microns and a combination of some and all of the biomass were pretreated using combined hydrothermal and acid-based, combined hydrothermal and alkali-based and hydrothermal only processes. The raw and pretreated biomass were also characterized by Fourier transform infrared spectroscopy (FT-IR), Brunauer–Emmett–Teller (BET), X-Ray diffraction (XRD), and Scanning electron microscopy (SEM) to determine the effects of the various pretreatments on the biomass being studied. The cellulose values of the raw biomass range from 25.8 wt% for cassava peels biomass to 40.0 wt% for sugar cane bagasse. The values of the cellulose content increased slightly with the pretreatment, ranging from 33.2 to 43.8 wt%. The results of the analysis indicate that the hydrothermal and alkaline-based pretreatment shows more severity on the different biomass being studied as seen from the pore characteristics results of corn cobs + rice husks biomass, which also shows that the combination of feedstocks can effectively improve the properties of the biomass in the bioethanol production process. The FTIR analysis also showed that the crystalline cellulose present in all the biomass was converted to the amorphous form after the pretreatment processes. The pore characteristics for mixed corn cobs and rice husks biomass have the highest specific surface area and pore volume of 1837 m2/g and 0.5570 cc/g respectively.

Investigation of the effects of pretreatment on the elemental composition of ash derived from selected Nigerian lignocellulosic biomass

“…Thorough mixing of the combined mixture of two or more biomass was ensured for uniformity in composition. Details of the pretreatment process can be obtained from previous work by the authors 15 .…”

“…This pretreatment process offers the advantage of eliminating lignin from the biomass more effectively. The technique also removes acetyl and uronic acid groups from hemicellulose, increasing the enzyme's accessibility to break down hemicellulose Pretreatment with alkali can also be done at low temperatures, pressures, and times 15 .…”

Hybridization of Selected Nigerian Lignocellulosic Biomass Feedstocks for Bioethanol Production: Modeling and Optimization of Pretreatment and Fermentation Process Parameters Using Response Surface Methodology

“…To study the effects of biomass combinations, 750 g each of 300 microns particle size cassava and yam peels biomass and corn cobs and rice husks biomass was measured and transferred into different vessels. The pretreatment and characterization of the biomass have been discussed in our previous work 16 . Approximately 10 liters of each of the pretreated biomass were obtained and made up to 15 liters by the addition of water and transferred to the fermentation vessels.…”

Agro-residues for clean electricity: in-lab trial of power generation from blended cocoa-kolanut wastes

“…Thus in [ 4 ], pine sawdust obtained from Tanzania was modelled for its suitability for energy production through the use of steam explosion pre-treatment method. The effects of pre-treatments of biomass using hydrothermal, acid-based and alkali-based processes have been investigated, with the results indicating that hydrothermal and alkaline-based processes have high severity on the biomass materials [ 5 ]. In [ 6 ], proximate-based regression models was developed for higher heating value (HHV) prediction of poultry waste, and it was found that the most accurate of the models contained linear and polynomial terms, as well as interaction effect; with the best-fit regression model having a higher R 2 and lower estimation errors than the existing proximate-based models.…”