Biocompositional and thermodecompositional analysis of South African agro‐waste corncob and husk towards production of biocommodities

Abstract

Biocompositional and thermodecompositional analyses of locally abundant agro‐wastes of South African corn were evaluated for their potential utilization as biocommodities via thermochemical and bioconversion processing. Corncob of Zea mays Zama star (white) & PAN 6Q‐252 (yellow) hybrid as well as the ear husks of South African sweet corn, Z. mays var. Saccharata were utilized in the beneficiation process. Proximate and elemental analyses were conducted to check for the moisture content, the ash content, the volatile matter, and the elemental composition of the agro‐waste samples. In addition, the thermal property of the waste, the surface chemistry and the calorific values were investigated using thermogravimetric analysis, Fourier‐transform infrared (FTIR) spectroscopy and bomb calorimetric technique, respectively. Significant amounts of alkali metals (Li, Na, and K) were found in the corn cob samples, and heavy metals such as thorium and uranium were detected in the ear husks, indicating that the biomass might not be suitable for use in thermochemical process. However, a relatively high volatile matter content recorded for the waste samples supports their use in thermochemical process with improved yield per gram of feed. These and other findings such as the high calorific value of the cob samples and the relatively low lignin‐to‐sugar ratio of the waste confirm previous reports regarding their suitability as feedstocks in thermo‐processing and bioprocessing. With the exception of the moisture content in ear husks, the minimal variation in the physicochemical property of the waste samples substantiates their suitability for co‐processing without major upsets in process kinetics. Results of other investigations such as the thermodecompositional behavior of the waste samples and the surface chemistry further shed light on the physicochemical property of the locally sourced lignocellulosic biomass waste samples. © 2017 Curtin University and John Wiley & Sons, Ltd.

Proximate Composition, Mineral Contents and Fatty Acids Profile of Selected Crop Residues Across Savannah Agro-Ecological Zones of Northern Nigeria

“…The level of copper is negligible in all the samples. The mineral contents of the crop residues analysed in the present study were low compared to those documented by and Abubakar et al (2016) and Awosusi et al (2017). The variations observed in the mineral contents of the crop residues might be attributed to environmental factors such as elevated ozone levels, water availability, and presence of light (Nour et al, 2014).…”

Valorisation of sweet corn (Zea mays) cob by extraction of valuable compounds

“…() and Awosusi et al . (). The minerals and trace elements content may vary in plants due to the influence of environmental conditions such as presence of light, water availability elevated CO 2 , elevated ozone levels and agricultural technologies (Nour et al ., ).…”

Corn Cob Char as Catalyst Support for Developing Carbon Nanotubes from Waste Polypropylene Plastics: Comparison of Activation Techniques

“…Waste PP showed considerably high volatile matter content depicting the presence of a greater composition of low molecular weight hydrocarbon, which is advantageous in utilizing waste PP as a cheap carbon feedstock for growing carbon nanomaterials. Furthermore, the high-volatile matter content of the biomass (corn cob) could also be linked to the easy bond breaking of the cellulose, hemicellulose and lignin components in the corn cob biomass, resulting in the release of low molecular weight hydrocarbon gases [ 36 , 37 ]. The ash content depicts the inorganic mineral content in biomass, biochar and waste PP.…”

“…From the result, the obtained carbon and potassium contents increased after thermochemical pro-cessing of the biomass into biochar, and the appearance of other metals is also observed. The compositional characteristics of corn cob and the corresponding char are reported to be affected by the soil type, type of soil nutrient applied, region where the corn plant was cultivated, etc., which could result in a variation in results obtained for biochar in relation to other reported findings from other researchers [36,38]. According to Srilek and Aggarangsi [39], high-temperature pyrolyzed corn cob biomass (biochar) has high lignin content and completely decomposed cellulose and hemicellulose contents, which could influence the overall inorganic composition and surface properties.…”