COCONUT SHELL

Chemical industries increasingly rely on catalytic processes, and more than 90% of large scale chemical transformations depend on catalysts. Some of the commonly used homogeneous catalysts in Fridel Crafts alkylation reaction are; BF3, H2SO4, HF, AlCl3. Though, readily available at low cost, they have several limitations and these include toxicity, difficulty in separation and recovery and disposal problems. These limitations have intensified the demand for sustainable, efficient, and environmentally benign heterogeneous catalysts. This study focuses on the development of metal-doped coconut-shell biochars as robust heterogeneous catalysts for the Friedel Crafts benzylation of toluene. Biochars derived from the coconut shell produced at different pyrolysis temperatures (350, 400, 450, 500, 600 and 700 °C) were characterized in terms of their physicochemical and textural properties, surface oxygen functional groups and surface morphology using standard methods. The coconut shell biochar (CSB) sample with the optimal textural properties (CSB450) was then co-pyrolysed with Fe³⁺, Zn²⁺, and Fe³⁺/Zn²⁺ ions to produce metal doped biochars (Fe³⁺ - doped, Zn²⁺- doped, and Fe³⁺/Zn²⁺-doped biochar). Central Composite Design (CCD) of the Response Surface Methodology (RSM) was employed to optimize the process variables (metal loading, pyrolysis temperature and pyrolysis time) for the co-pyrolysis reaction. Similarly, RSM was used to optimized the process variables (mole ratio of toluene: benzyl chloride (T:BC), reaction temperature and reaction time) on benzyl chloride conversion to benzylated toluenes with the metal doped biochars. RSM-derived optimal conditions resulted in enhanced specific surface areas of 2098.04 m2 .g-1 for the Fe³⁺-doped biochar, 1721.40 m2 .g-1 for the Zn²⁺-doped biochar, and 2124.5 m2 .g-1 for the Fe³⁺/Zn²⁺-doped biochar. Compared with the pristine biochar (CSB450), the metal doped biochars (MBCs) showed improved physicochemical properties and textural properties. In addition, surface elemental analysis confirmed the successful incorporation of the Fe (10.09%), Zn (5.17%) and Fe/Zn (9.44/6.51%) on the MBCs. The results of the conversion process showed that the reaction temperature, mole ratio, and reaction time significantly affected benzyl chloride conversion with the metal doped biochar. Three novel models were developed for benzyl chloride conversion process. From the models, we predicted optimized process conditions; optimum benzyl chloride conversion of 93% was found for Fe3+/Zn2+ - doped biochar, with values of 87 and 81% for the Fe3+ - and Zn2+ - doped biochar respectively. This research established metal doped coconut shell biochar as an effective, low-cost, and environmentally friendly heterogeneous catalysts for organic transformations, presenting a viable alternative to conventional corrosive and non-recyclable catalysts in industrial alkylation processes.

Chemical industries increasingly rely on catalytic processes, and more than 90% of large scale chemical transformations depend on catalysts. Some of the commonly used homogeneous catalysts in Fridel Crafts alkylation reaction are; BF3, H2SO4, HF, AlCl3. Though, readily available at low cost, they have several limitations and these include toxicity, difficulty in separation and recovery and disposal problems. These limitations have intensified the demand for sustainable, efficient, and environmentally benign heterogeneous catalysts. This study focuses on the development of metal-doped coconut-shell biochars as robust heterogeneous catalysts for the Friedel Crafts benzylation of toluene. Biochars derived from the coconut shell produced at different pyrolysis temperatures (350, 400, 450, 500, 600 and 700 °C) were characterized in terms of their physicochemical and textural properties, surface oxygen functional groups and surface morphology using standard methods. The coconut shell biochar (CSB) sample with the optimal textural properties (CSB450) was then co-pyrolysed with Fe³⁺, Zn²⁺, and Fe³⁺/Zn²⁺ ions to produce metal doped biochars (Fe³⁺ - doped, Zn²⁺- doped, and Fe³⁺/Zn²⁺-doped biochar). Central Composite Design (CCD) of the Response Surface Methodology (RSM) was employed to optimize the process variables (metal loading, pyrolysis temperature and pyrolysis time) for the co-pyrolysis reaction. Similarly, RSM was used to optimized the process variables (mole ratio of toluene: benzyl chloride (T:BC), reaction temperature and reaction time) on benzyl chloride conversion to benzylated toluenes with the metal doped biochars. RSM-derived optimal conditions resulted in enhanced specific surface areas of 2098.04 m2 .g-1 for the Fe³⁺-doped biochar, 1721.40 m2 .g-1 for the Zn²⁺-doped biochar, and 2124.5 m2 .g-1 for the Fe³⁺/Zn²⁺-doped biochar. Compared with the pristine biochar (CSB450), the metal doped biochars (MBCs) showed improved physicochemical properties and textural properties. In addition, surface elemental analysis confirmed the successful incorporation of the Fe (10.09%), Zn (5.17%) and Fe/Zn (9.44/6.51%) on the MBCs. The results of the conversion process showed that the reaction temperature, mole ratio, and reaction time significantly affected benzyl chloride conversion with the metal doped biochar. Three novel models were developed for benzyl chloride conversion process. From the models, we predicted optimized process conditions; optimum benzyl chloride conversion of 93% was found for Fe3+/Zn2+ - doped biochar, with values of 87 and 81% for the Fe3+ - and Zn2+ - doped biochar respectively. This research established metal doped coconut shell biochar as an effective, low-cost, and environmentally friendly heterogeneous catalysts for organic transformations, presenting a viable alternative to conventional corrosive and non-recyclable catalysts in industrial alkylation processes.

In this study, coconut oil (CO), which had been characterised and shown to have an Acid Value of 5.8 mg KOH/g, was utilised to optimise the synthesis of biodiesel, which was catalysed by a bio-based bi-functional catalyst, by esterifying and trans-esterifying the CO simultaneously. The carbonised and sulfurized coconut shell was used to create the acid precursor for the bio-based bi-functional catalyst, while the calcined and KOH-treated crab shell was used to create the base precursor. Both precursors were then impregnated. The synthesised bio-based catalyst was characterised using SEM, XRD, FTIR, and BET/BJH techniques. The experimental design was optimised using Box Behnken Design (BBD) for the simultaneous esterification and transesterification of CO. The measured response was the production of coconut oil methyl ester (COME). The methanol-to-oil molar ratio, reaction temperature, and catalyst loading had the biggest effects on COME yield among the factors. The study's ideal conditions were determined to be a 16.75:1 methanol to oil ratio, 1% catalyst loading, 58.19 °C, and a reaction duration of 78.76 min, yielding a COME yield of 85.73 wt% and an AV of 0.28 mg KOH/g. RSM and ANFIS models were compared using statistical data, and the results showed that the ANFIS model was more accurate than the RSM model. After characterising the COME obtained in the best possible condition, it was determined that its physicochemical parameters satisfied the ASTM D6751 and EN 14214 standards for biodiesel.

The high cost of concrete materials in building projects has been a concern in Nigeria. This project was carried out to investigate and compare the use of Palm kernel shell and Coconut shell in replacement of coarse aggregate in 1:1:2 concrete mix design and 0.5 water/cement ratio. It aimed at determining the maximum partial replacement of by Palm kernel shell and Coconut shell in concrete and comparing their compressive strength and other relavant mechanical properties. A total of 143 cubes of size 100mm × 100mm × 100mm were casted, the test conducted include: Sieve analysis test, Workability (Slump) test, Density test, Compressive strength test and Water absorbion test. From Sieve analysis result obtained, the values obtained shows that the PKS is poorly graded and will contain lot of voids while the CS contain smaller void. From the slump test results, true slump was obtained for both PKS and CS as coarse aggregate replacement as the slump values were within 7-42mm which is medium workability range, although the CS concrete had higher slump compared to PKS. Both Palm kernel shell and Coconut shell concrete had density greater than 2000kg/m³ for light weight concrete, the results shows that PKS concrete has lesser density compared to CS concrete, meaning it offers better sound insulation and fire resistance. The results shows that for PKS concrete the maximum compressive strength obtained and is useful was 21.93N/mm² (25% replacement) but with poor workability , moreover the useful maximum compressive strength for CS concrete was 20N/mm² (40% replacement) but with poor workability. The results also showed that the useful maximum compressive strength of PKS concrete and CS concrete with good workability was 28.63N/mm² (5% replacement) and 29.48N/mm² (5% replacement) respectively. CS as coarse aggregate had an appreciable strength compared to PKS as a coarse aggregate in concrete, considering strength/economic ratio, Coconut shell is recommended to be used as a partial replacement of coarse aggregate in making light weight concrete. The cost benefit analysis showed that 40% replacement with Coconut ahell in 1m³ of concrete there is a savings of #3,120 and at 35 replacement with In 1m³ of concrete there is a savings of #4,452.

The discharge of untreated textile wastewater containing synthetic dyes poses significant environmental and public health risks due to its toxicity and resistance to conventional degradation processes. This research explores a sustainable and cost-effective solution by developing and evaluating a novel activated carbon (AC) adsorbent derived from a blend of two abundant agricultural wastes: Palm Kernel Shell (PKS) and Coconut Shell (CS).This study aimed to treat synthetic wastewater contaminated with Methyl Red dye. The PKS and CS were individually carbonized and chemically activated using potassium hydroxide (KOH). The resulting activated carbons were blended in a 1:1 ratio to create a composite adsorbent (PKS-CS AC). The adsorbent was extensively characterized using Brunauer-Emmett-Teller (BET) analysis, which revealed a specific surface area of 275.762 m²/g and a well-developed microporous and mesoporous structure, complemented by Fourier-Transform Infrared Spectroscopy (FTIR) that identified key functional groups (O-H, C=O, C-O) crucial for adsorption.A series of batch adsorption experiments were conducted, and the process was optimized using Response Surface Methodology (RSM) based on a Central Composite Design (CCD). The influence of critical operational parameters—adsorbent dosage (PKS-AC and CS-AC), contact time, and initial dye concentration—on Methyl Red removal efficiency was investigated. The ANOVA of the quadratic model confirmed its high significance, with an R² value of 0.9501, indicating the model accurately represented the experimental data. The optimization results identified the optimal conditions as 1.65 g/L of CS-AC, 6.13 g/L of PKS-AC, a contact time of 70.75 minutes, and an initial dye concentration of 328.1 mg/L, achieving a predicted dye removal efficiency of 93.75%

The influence of dye concentration, adsorbent dosage, and contact time on the % removal of methylene blue dye (textile effluent) from aqueous solution was optimized and evaluated using a three-variable Box-Behnken design (BBD) in combination with response surface methodology (RSM). Coconut shell was utilized to make the adsorbent, which was then activated with H3PO4 after being carbonized at 600°C for an hour. Three variables dye concentration (50–200 mg/l), adsorbent dosage (g/100 ml), and contact time (10–60 mins), were varied to treat the dye solution. The responses of the linear and quadratic models that were developed for % dye removal from aqueous solution were significantly influenced by all three parameters, according to a statistical analysis of the data with p < 0.0001, the models were significant and demonstrated a strong fit with the experimental data. The adsorbent dosage and contact time had a positive impact on the percentage of dye removal. The process was optimized, and the maximum dye removal of 82% was attained at optimum dye concentration, adsorbent dosage, and contact time of 125 mg/l, 0.55 g/100 ml, and 35 min

In this study, the fabrication of a hybrid composite abrasive sandpaper using coconut shell and crab shell particles embedded in polyester resin is investigated, aiming to address resource depletion and environmental issues associated with conventional synthetic abrasive materials. The mechanical properties and abrasive behavior of the fabricated composite are investigated through meticulous methodology involving sourcing, cleaning, drying, mechanical processing, and production of abrasive specimens. Varying levels of hardness, compressive strength, density, and water absorption are revealed across different compositions of coconut shell and crab shell. The most optimal properties are demonstrated by Sample 5, with a proportion of 35% coconut shell and 65% crab shell, which exhibits reduced water absorption, enhanced hardness, competitive compressive strength, and favorable density characteristics. Comparative analysis with Garnet sandpaper suggests that the hybrid composite sandpaper samples offer competitive or superior performance. Further research is recommended to optimize composition, utilize advanced characterization techniques, and explore sustainable manufacturing practices to enhance the performance and applicability of hybrid composite abrasive materials.

This study evaluated the compressive strength of coconut shell concrete for concrete construction by partially replacing coarse aggregate with crushed coconut shells at varying levels (0%, 5%, 10%, and 15%). The primary aim was to determine the optimum replacement percentage that delivers satisfactory mechanical performance including compressive strength, split tensile strength, and flexural strength while promoting sustainability and reducing concrete weight. This investigation is driven by the need to recycle agricultural waste and improve the environmental footprint of conventional concrete in harsh service conditions. A series of experiments were conducted on concrete mixes with replacement levels of 0%, 5%, 10%, and 15% by weight, prepared with a constant water-to-cement ratio of 0.48. Fresh concrete workability was assessed using slump tests, which indicated a reduction in
slump as the percentage of coconut shell replacement increased. Hardened concrete specimens were cast in cube form and cured for 7, 14, and 28 days. Compressive strength tests were then carried out using a universal compression testing machine with a 2000 kN capacity. The failure load of each cube was recorded, and compressive strength was calculated using the formula: Strength = (Maximum Load)/(Cross-sectional Area). The results show that the control mix (0% replacement) achieved average compressive strengths of 21.09 N/mm² at 7 days, 23.90 N/mm² at 14 days, and 30.51 N/mm² at 28 days. Although increasing coconut shell content resulted in higher water absorption and a slight reduction in workability, the mix with 5% replacement maintained compressive strength values closest to the control, while meeting the target design characteristic strength (approximately 20 N/mm²). These findings indicate that a 5% replacement level provides the optimal balance between sustainability and mechanical performance, making coconut shell concrete a viable alternative for concrete applications.