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

Abstract

Lignocellulosic biomass is an important source of renewable energy and a potential replacement for fossil fuels. In this work, the X-ray fluorescence (XRF) method was used to analyze the elemental composition of raw and pretreated lignocellulosic biomass of cassava peels, corn cobs, rice husks, sugarcane bagasse, yam peels, and mixtures of cassava peels and yam peels, corn cobs and rice husks and all five biomass samples combined. The influence of particle size on elemental properties was investigated by screening the selected biomass into two size fractions, of an average of 300 and 435 µm, respectively. The total concentration of Mg, Al, Si, P, S, Cl, Ca, Ti, Cr, Mn, Fe, Co, Cu, Zn, Sn, Ni, Br, Mo, Ba, Hg, and Pb were determined for each of the biomass samples before and after the different pretreatments adopted in this study. From the results of the analysis, there was a significant reduction in the concentration of calcium in all the analyzed biomass after the alkaline pretreatment with rice husks biomass having the lowest concentration of 66 ppm after the alkaline pretreatment. The sulfur content of the acid pretreated biomass increased considerably which is likely due to the sulfuric acid used for the acid pretreatment. The fact that a mixture of biomass feedstock affects the properties of the biomass after pretreatment was validated in the mixed biomass of cassava peels and yam peels biomass as an example. The concentration of Mg in the mixed biomass was 1441 ppm but was 200 ppm and 353 ppm in individual cassava peels and yam peels respectively. The results of this study demonstrated that pretreated mixtures of biomass have varied elemental compositions, which could be an important factor affecting downstream processes, especially if a hybrid feedstock is used in a large-scale application.

Criteria for Assessing Sustainability of Lignocellulosic Wastes: Applied to the Cellulose Nanofibril Packaging Production in the UK

“…For example, recycled pulp (i.e., dried once), contrasting to virgin pulp (i.e., never-dried), produces CNF films with reduced tensile strength and swelling capacity, thereby reducing recyclability [ 28 , 48 , 78 ]. Whereas mixed wastes, e.g., food and garden waste in MSW, possessing heterogenous compositions may cause high costs, requiring more flexible and complex processing in the biorefineries, compared to their homogeneous fractions deriving from forestry and agriculture [ 79 , 80 , 81 ]. In the UK ( Table 5 ), the primary waste streams (F1–F15) are likely to produce packaging films with better strength and recyclability, albeit using less processing compared to the processed and mixed wastes from flows F16–F28.…”

Chemical, Thermogravimetric and Elemental Characterization of Nigerian Groundnut and Cowpea Shells for Sustainable Valorization

“…They also have an adverse effect ( fouling, slagging, agglomeration, and corrosion) on power generation plants that use biomass for direct combustion [41]. However, research studies have shown that pretreatment of biomass cassava peels, corn cobs, rice husks, sugarcane bagasse, yam peels [44]; pine bark and switchgrass [41]; rice and wheat straw [45] reduces these elements to minimal concentration. Therefore, the low concentration of elemental compounds in Nigeria groundnut shells and cowpea shells is an added advantage, since reducing its elemental composition will require minimal pretreatment.…”

Criteria for Assessing Sustainability of Lignocellulosic Wastes: Applied to the Cellulose Nanofibril Packaging Production in the UK

“…This criterion indicates whether an LC stream comprises raw, processed, homogenous or mixed materials, determining its requirements for handling or processing operations and the resulting bioplastics quality [77]. Refined biomass is different by chemical composition and processing history than their raw counterpart, therefore results in CNF films differing by properties, processability or performance [28,29,46].…”