Kidney bean (Phaseolus Vulgaris L.) pod husks as a potential source of cellulose for the synthesis of bioplastics · Electronic Theses and Dissertations

Author

Kuboya, Mitchell

Title

Kidney bean (Phaseolus Vulgaris L.) pod husks as a potential source of cellulose for the synthesis of bioplastics

Abstract

Synthetic plastics are widely used as packaging materials in all regions of the world because of their suppleness, little weight and affordability. However, the continued use
of synthetic plastics pollutes waterways and changes sites where humans or animals
live, reducing the ability of ecosystems to suit accordingly to climate change. and has direct impacts on livelihoods, food production capacity and society. Agri-food operations generate billions of tonnes of agricultural waste each year. Amidst the principal parts of lignocellulosic biomass, cellulose has distinct features because it is a renewable organic material found in copious supply in the biosphere. In this study, we
investigated waste from P. vulgaris pod husks as a potential source of cellulose for the
synthesis of bioplastic. The yield of the extracted cellulose was 30%. Different concentrations of glycerol (a plasticizer) and cellulose were used to synthesize three bioplastics, 25% and 35% for sample A, 35% and 50% for sample B and 12.5% and 75% for sample C. The bioplastics were synthesized using the acid hydrolysis method and the method of casting and evaporation. The synthesized bioplastics were characterized using swelling tests and obtained weight differences in chloroform with sample A having 0.01 g, sample B and sample C with 0.02 g, in methanol with sample A having 0.05 g, sample B with 0.03 g and sample C with 0.04 g and in water with sample A having 0.09 g, sample B with 0.1 g and sample C with 0.08 g. Solubility tests where the bioplastics were insoluble in a number of organic solvents and soluble in sulfuric acid were also conducted. A biodegradability test was performed, %weight losses were noted, sample A with 22.38%, sample B with 38.97% and sample C with 41.43%. Characterization tests were also performed, peaks were observed at wavenumbers 1019.33 cm-1, 2683.41 cm-1, 1600.62 cm-1, 1318.99 cm-1, 3329.66 cm-1 for the cellulose extract and for the bio-plastic ;3000 to 3500 cm-1 for samples A and B, sample C had a less pronounced peak at 3000 cm-1. Melting point was also determined and sample A had 104 0C, sample B had 102 0C and sample C had 100 0C. This study showed that Phaseolus vulgaris pod husks could be a potential source of cellulose for the production a valuable product, bioplastic, thereby reducing the environmental impact of synthetic plastics.

Date

2023

Publisher

BUSE

Keywords

Kidney bean (Phaseolus Vulgaris L.)

Phaseolus Vulgaris L.

Cellulose

Supervisor

Dr Gwatidzo, L.