Study on the Improvement of Physical and Mechanical Properties of Ugwuoba Clay Using Palm Stalk Ash

Abstract

This study investigates the enhancement of the microstructural, physical and mechanical properties of Ugwuoba clay through the incorporation of palm stalk ash (PSA) as a reinforcing additive. Ugwuoba clay reinforced with 10wt.%, 20wt.%, 30wt.%, and 40wt.% of PSA were prepared and tested for flexural strength, refractoriness, thermal shock resistance, and other physico-mechanical properties. Results indicate that the inclusion of PSA has a significant influence on the microstructure of the Ugwuoba clay. Additionally, the addition of PSA enhances the flexural strength but reduces both refractoriness and thermal shock resistance with an increasing weight fraction of PSA. Also, the physic-mechanical properties (linear shrinkage, bulk density, modulus of rupture, apparent porosity, and water absorption) of one of the reinforced samples (30wt.% PSA reinforced Ugwuoba clay composite) at increasing sintering temperature between 900^oC to 1300^oC was compared to those of the unreinforced Ugwuoba clay. Results show significant influence on the physico-mechanical properties with increasing sintering temperature.  The study demonstrates that PSA can effectively enhance the mechanical properties of Ugwuoba clay with minimal reduction in its thermal properties. However, this approach provides an insight into sustainable utilisation of agricultural waste and contributes to value-added material development, while further studies can be carried out to improve on the thermal properties affected. These findings highlight PSA’s potential as a sustainable reinforcement in clay-based ceramics for moderate thermal applications such as kiln linings, insulating bricks, and structural ceramics.