This study reports the usage of chemically impregnated coconut coir waste (CICCW) as a low-cost adsorbent for the desulfurization of feed diesel. The characterization of the developed adsorbent was focused on quantitative analysis (carbon yield %, proximate, ultimate, carbon surface functionalities, BET surface area and porosity distribution, and particle size analysis), qualitative analysis (FTIR), and optical analysis (SEM). Batch experiments with feed diesel having a total sulfur concentration of 2,050 mg L-1 were conducted to optimize the adsorption parameters such as adsorbent dose, temperature, and contact time. The adsorption process shows an optimum dose of 1 g/20 mL, and the equilibrium is attained in 3 h. The adsorption of sulfur onto the adsorbent at optimum temperature 293 K is regulated by external mass transfer (diffusion into mesopores) followed by a steady adsorption phase with intra-particle diffusion in micropores. A Fickian mechanism controls the diffusion of sulfur molecules from the solution onto the surface of the adsorbent. Freundlich adsorption isotherm illustrates the equilibrium adsorption data very well. The negative value of ΔGo (-27.61 kJ mol-1) and ΔSo (-44.56 J K-1 mol-1) indicates the feasibility, spontaneity of the adsorption process and justified the decrease in the randomness of adsorbed sulfur molecules onto the adsorbent surface, respectively. The exhausted CICCW can be effectively regenerated by methanol and reutilized for three adsorption–desorption cycles. The approximate cost of preparation of the adsorbent was USD 10.714 per kg. These results clearly proved the feasibility of the developed low-cost adsorbent (CICCW) as a good candidate for the desulfurization of feed diesel.

The present work aims to assess the pressure-settlement behaviour of sand beds under a square footing reinforced with coir geotextile using the PLAXIS 3D software. The angle of internal friction of sand was varied from 28° to 38°. The effect of length of coir geotextile (1B, 2B, 3B, 4B, and 5B; B is width of footing) and position of coir geotextile (0.2B, 0.4B, 0.6B, 0.8B, and 1B) to ultimate bearing capacity of sand were examined. A remarkable improvement in ultimate bearing capacity of sand beds was obtained with provision of coir geotextiles.  It was observed that the bearing capacity of sand increases by placing coir geotextiles up to a depth of 0.4B from base of footing, thereafter it starts decreasing. The optimum length of coir geotextile was found as 4B-5B. An insignificant improvement in the bearing capacity ratio of sand reinforced with coir geotextile was observed at higher values of angle of internal friction.

Due to significant environmental advantages, biocomposites have recently received increasing attention. In the present research, strength of hat-shaped coir fiber biocomposites tubes reinforced with nano powder was evaluated experimentally under 3-point bending tests. The tubes were manufactured using hand lay-up technique and based on Taguchi design of experiment. The effects of different parameters including fiber loading, type of nano powder and its weight percentage and also weight percentage of NaOH in alkali treatment were analyzed. Optimization was also performed using Taguchi L8 orthogonal array. Moreover, analysis of variance (ANOVA) was conducted to determine the significance of the parameters. In this study, finite element model was also created in ABAQUS software to compare with the results obtained from the experiments to achieve validated finite element model. There was a good agreement between the results from experiments and those obtained in numerical simulations.

Background: As objective of this study was focused on efficacy of composting of a recalcitrant organic waste material, co-composting of coir pith with cow manure and rice bran was endeavored to evaluate influence of initial C/N ratios, i.e., 30, 25, and 20, on physico-chemical changes, e.g., temperature, pH, organic matter (OM) degradation, and total nitrogen (TN) losses.Results: Results showed that OM and TN losses were significantly affected by C/N ratio (p<0.05), whereas C/N ratio played insignificant role on temperature and pH evolution within the pile (p>0.05) during composting process. OM and TN losses were highest within the first 2 weeks of thermophilic phase. Through the composting process, pile with 25 C/N ratio showed the highest biodegradation rate constant of organic matter (k=0.309 day-1) and the highest TN losses (41.9%), while pile with C/N ratio of 30 showed the lowest N loss (-7.3%). However, for all three compost piles, maturity, as indicated by the pile temperature converging to the ambient temperature, was attained within 1 month post-composting.Conclusion: Results suggested that simple pile turning yielded effective co-composting of coir pith under comparatively low C/N ratio. Considering the composting performance and the amount of coir pith to be utilized, the initial C/N ratio of 30 was considered suitable for coir pith composting.

Using a hand lay-up approach, both orange peel and coconut coir fibres are used in particulate form with an epoxy matrix to create partly green biodegradable composites. The findings indicate great opportunities for employing these natural fibres. The thermal conductivity of orange peel and coconut-coir epoxy composites was measured experimentally for various volume fractions of particulate fibres. The experimental findings show that as fibre concentration increases, thermal conductivity decreases. Experimental data are compared to theoretical models to determine the change in thermal conductivity with fibre amount fraction.There was a clear correlation between the hypotheses and the actual results. Regression analysis using Python programming is also done for the prediction of the thermal properties of particulate orange peel and coconut-coir fibre composites. It is observed that coir fibre composites outperformed the orange peel, indicating that the coir fibre composite is a proper thermal insulator that can be used in many industries, like the automotive industry, buildings, and steam pipes, to reduce heat transfer and thereby save a lot of energy.

This work investigates the physical, chemical, and mechanical properties of coir-coconut husk powder reinforced low-density polyethylene composites exposed to an aggressive (acidic) environment. The composites were prepared by the melt mixing moulding method. The fabricated composites were immersed in an acidic environment of pH 2. 2 for a period of 27, 54, and 81 days. Two variants of samples were prepared namely: unreinforced samples (C1) and reinforced samples (C2). The unreinforced polymer samples (C1) were obtained before ageing (C1-0d), and after ageing (C1-27d, C1-54d, and C1-81d), and also, the reinforced polymer samples (C2) were obtained before ageing (C2-0d), and after ageing (C2-27d, C2-54d and C2-81d). Hardness, X-ray diffraction (XRD), friction, wear, and water absorption studies were carried out on the samples. From the experimental results, after immersion in the acidic solution for 27, 54, and 81 days, the hardness values of samples C1 (acid-aged variants) increased by 12. 3, 19. 4, and 31. 5% with hardness values of 16. 53 Hv, 18. 0 Hv, and 21. 7 Hv, respectively. For C2 samples, the hardness value increased by 6. 50% and 17. 3% after immersion in the acidic solution for 27 and 54 days with increments from 35. 47 Hv (hardness value for C2-0d sample) to 37. 93 Hv and 42. 87 Hv, respectively. The crystallinity of the LDPE polymer-C2-54d sample, indicates its increasing strength since the intermolecular bonding is more significant in the crystalline phase. The study concluded that acid ageing has a noticeable influence on the physico-chemical and mechanical properties of coir-coconut husk powder reinforced low-density LDPE composites.