Extraction of lignin from cocoa pod husk theobroma cacao)

Project Abstract

Cocoa pod husk, a major byproduct of the cocoa industry, is rich in lignin, a complex organic polymer. This study aimed to extract lignin from cocoa pod husk (Theobroma cacao) using a combination of alkaline and acid hydrolysis methods. The extraction process involved several steps including grinding the cocoa pod husks, alkaline treatment to remove hemicellulose and cellulose, acid hydrolysis to separate lignin from the remaining components, and purification of the extracted lignin. The extracted lignin was characterized using various analytical techniques such as Fourier-transform infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR) spectroscopy, and thermogravimetric analysis (TGA). The results showed that the combination of alkaline and acid hydrolysis methods was effective in extracting lignin from cocoa pod husk. The FTIR and NMR spectra confirmed the presence of lignin in the extracted samples, with characteristic peaks corresponding to lignin structures. TGA analysis revealed the thermal stability of the extracted lignin, making it a potential candidate for various applications in industries such as adhesives, biofuels, and bioplastics. Furthermore, the study explored the potential applications of the extracted lignin, including its use as a bio-based adhesive in wood composites. The extracted lignin showed promising adhesive properties, with good adhesion strength and water resistance when used in combination with other biopolymers. This suggests that lignin from cocoa pod husk could serve as a sustainable alternative to synthetic adhesives commonly used in the wood industry. Overall, the extraction of lignin from cocoa pod husk presents a sustainable solution for valorizing this agricultural waste and producing value-added products. The combination of alkaline and acid hydrolysis methods proved to be an efficient way to extract lignin from cocoa pod husk, with the potential to be scaled up for industrial applications. The extracted lignin showed promising properties for various applications, highlighting its potential as a renewable and eco-friendly resource for the development of bio-based materials.

Project Overview

<p> </p><p><strong>&nbsp;INTRODUCTION</strong></p><p>Cocoa (<em>Theobroma cacao L</em>.) fruits are important commodity of economic value since the seeds or beans is used to produce high demand products such as cocoa powder, butter and chocolate. The processing of cocoa fruits generates a large amount of cocoa pod husk discard as wastes (<em>Alemawor et al.,</em>&nbsp;2009). Cocoa pod husk represents between 70 to 75% of the whole cocoa fruit weight where each ton of cocoa fruit will produce between 700 to 750 kg of cocoa pod husks (Cruz <em>et al., </em>2012). In Malaysia, the plantation of cocoa is over 20,643 hectre (Malaysia Koko Board, 2011). Hence, it can be estimated at least 320,000 kg of cocoa pod husk is generated after processing. Conventionally, these organic wastes is shipped away for processing or disposed to landfill. These large quantities of cocoa pod husk could yield a large quantity of fibrous materials which might be suitable as alternative resources especially in pulp and paper making industries.</p><p>In order to maximize the utilization of organic wastes or non-wood fibres for pulp and paper production, a complete study of its chemical and morphological properties is required. In this context, the main objective of this work is to investigate the chemical compositions of cassava peels and cacao pod husks fibre used for pulp and papermaking industry. In addition, characterization of surface morphology in both non-wood fibres was also determined. The results obtained in this study could be utilised in assessing the agriculture wastes potential as raw materials for pulp and paper production industries<strong>.</strong></p><p>Lignin found in cacao is high complex macromolecule linked together by different types of bonds, including alkyl-aryl, alkyl-alkyl and aryl-aryl ether bonds (Kumar <em>et al.,</em>&nbsp;2011). It obstructs enzymes from degradation associated &nbsp;with structural carbohydrates (Taherzadeh and Karimi, 2010). Therefore, prior treatment of lignocellulosic feedstocks, to remove or denature lignin, is essential for achieving a high yield of fermentable sugars (Yang and Wyman, 2012; Carroll and Somerville, 2010). Plant by-products differ in monolignol constituents of lignin’s and lignin chemistry can vary depending on its origin. The characterization of lignin is critical to the optimization of pre-treatment parameters in the cellulosic ethanol production process. It on this background that this study examines the extraction and characterization of lignin using cocoa (<em>Theobroma</em>&nbsp;<em>cacoa</em>) pod husk.</p><p>The aim of the study is to extract lignin and to characterize the lignin extracted from the pod husk of cacao pod. Specific objectives are</p><ol><li>To quantify the amount of lignin content of cocao(<em>Theobroma</em>&nbsp;<em>cacoa</em>) pod.</li><li>To investigate the proximate content of cocoa pod with respect to it ash content, moisture content, carbon content and surface area.</li><li>To characterize the lignin content of cocoa pod.</li></ol><p>&nbsp;</p><ul><li><strong>Significance of the study</strong></li></ul><p>The study is significant since it will quantify the amount of lignin present in cocoa pod and the proximate content of cocoa pod. The study will also highlight the characteristics of cocoa pod.</p><p>The scope of the study covers the extraction and characterization of cocoa pod husk and proximate analysis of cocoa pod.</p> <br><p></p>