Search Results (32)

Horticultural substrates based on coconut fibre are among the most commonly used growing media, but with limited durability. This study presents methods for modifying coconut fibre through surface coating with biopolymers, where polymerisation was initiated in the applied solution. Additionally, the suitability of adding pelletised biochar was analysed. A biomonomer derived from wood processing was used both for fibre surface modification and for binding biochar into pellets. Surface modification through biopolymer coating resulted in changes to selected physicochemical properties. It was found that the coating significantly altered the porosity of the substrate. Depending on the type of coconut fibre, the differences in porosity compared to the unmodified substrate ranged from 12 to 24%. This directly influenced bulk density, which is a crucial parameter in the preparation of substrates for plant growth. The surface properties of the modified substrates also affected sorption and retention capacities. From the perspective of plant production, the supply of bioavailable forms of potassium and phosphorus is essential. Coating and the addition of pelletised biochar, regardless of the type of fibre used, significantly increased the release of PO₄³⁻ and K⁺ compared to unmodified substrates. The physiological parameters in plants confirmed the suitability of the modified substrates for plant production. Full article

In 2022, the building sector accounted for 30% of global energy demand and 27% of CO₂ emissions, of which approximately 9% came from building material production. To mitigate this impact, it is critical to develop sustainable alternatives that reduce the environmental footprint of construction materials. This paper presents an original study where the effect of coconut fibre as a reinforcing material in gypsum composites is analysed. These plant-based fibres reduce the composite’s density, improve thermal behaviour, and integrate circular economy criteria in construction. In this way, a physico-mechanical characterisation of these novel gypsum-based composites is addressed, and their potential application for developing prefabricated slabs is innovatively explored. Composites were prepared with coconut fibre incorporation in volume up to 17.5%, and mechanical and thermal properties and their behaviour under water action were evaluated. The results indicate that the fibre addition reduced density by about 10.0%, improved flexural strength by 20.5% and compressive strength by 28.4%, and decreased thermal conductivity by 56.3%, which increased the energy efficiency of the building facade by 7.8%. In addition, hydrophobic properties improved, reducing capillary absorption by 15.9% and open porosity by 3.3%. These findings confirm the technical feasibility of coconut fibre-reinforced plaster for application in prefabricated wall and ceiling elements, promoting the efficient use of natural resources and driving the development of sustainable building materials. Full article

Fermentation of pumpkin puree and mature coconut water using water kefir grains is a potential method for producing a novel functional non-dairy-based probiotic drink. In the present study, response surface methodology based on Box–Behnken design (RSM-BBD) was used to optimise fermentation temperature and substrates’ concentrations. The optimised fermentation temperature, pumpkin puree, and brown sugar concentrations of pumpkin-based mature coconut water kefir beverage (PWKC) were 27 °C, 20%, and 10% w/v, respectively. The optimised PWKC (PWKC_opt) obtained an overall acceptability (OA) score of 4.03, with a desirable Lactobacillus count (6.41 Log CFU/mL), 0.68% v/v lactic acid content, 31% of water kefir grains’ biomass growth rate, and fermentation time (to reach pH 4.5) of 4.5 h. The optimized beverage, PWKC_opt, contained 3.26% proteins, 2.75% dietary fibre, 2186.33 mg/L of potassium, 180.67 mg/L phosphorus, and 137.33 mg/L calcium and had a total phenolic content of 89.93 mg GAE/100 mL, flavonoid content of 49.94 mg QE/100 mL, and carotenoid content of 33.24 mg/100 mL, with antioxidant activity (FRAP: 169.17 mM Fe(II)/100 mL, IC₅₀ value of DPPH free radicals scavenging activity: 27.17 mg/mL). Water kefir microorganisms in PWKC_opt remained stable for at least 56 days at 4 °C. Therefore, PWKC_opt might potentially serve as a value-added product, offering a basis for sustainable development within both the coconut and pumpkin industries. Full article

This study proposes a novel test method and corresponding procedure to evaluate how coconut fibres affect crack propagation rates resulting from plastic shrinkage during the accelerated drying of concrete slabs. The experiment employed concrete plate specimens, which were used to simulate slab structural elements with a surface dimension notably greater than their thickness. These slabs were reinforced with coconut fibre with 0.5%, 0.75%, and 1% fibre content. A wind tunnel was designed to simulate two significant climate parameters (wind speed and air temperature), which could impact the cracking behaviour of surface elements. The proposed wind tunnel allowed air temperature to be controlled alongside wind speed while monitoring moisture loss and the cracking propagation process. During testing, a photographic recording method was used to evaluate cracking behaviour, with the total crack length serving as a parameter to assess the impact of fibre content on the crack propagation of slab surfaces. Additionally, crack depth was measured using ultrasound equipment. The results indicate that the proposed test method was appropriate for future research, allowing for the evaluation of the effect of natural fibres on the plastic shrinkage behaviour of surface elements under controlled environmental conditions. Based on initial studies and the results obtained through the proposed test method, concrete containing 0.75% fibre content exhibited significantly reduced crack propagation on slab surfaces, as well as a reduction in the crack depth caused by plastic shrinkage during the early age of the concrete. Full article

Vegetation mats for horticulture and landscaping usually consist of coconut fibre and straw. They have hardly any available nutrients and serve only as a carrier material for plant growth. Water capacity is low. By incorporating raw sheep‘s wool, nutrients, such as nitrogen, potassium, and sulphur can positively influence the nutrient content of the carrier material. Water storage and water holding capacity are increased by the wool. In this study, three different thick-layered vegetation mats with different proportions of sheep’s wool and coir fibres were developed for the pre-cultivation of perennials. The focus is on the evaluation of sheep’s wool as a carrier material compared to pure coconut fibre as well as the plant growth of the eight perennial species used (Achillea clypeolata ‘Moonshine’, Achnatherum calamagrostis ‘Algäu’, Anaphalis triplinervis, Aster dumosus ‘Prof. Anton Kippenberg’, Aster dumosus ‘Silberball’, Centranthus ruber ‘Coccineus’, Coreopsis verticillata, Salvia nemorosa ‘Rosakönigin’). The vegetation mats with sheep’s wool (V1–V3) contained 192.6, 154.0, and 283.5 g nitrogen (N)/m² and the coir mats (V4) contained 7.5 g N/m². The water content ranged from 16.0 to 22.1 vol% for the sheep’s wool mats and 12.6 vol% for the coir mat at pF1 (is equal to matrix potential at −10 hPa). The air content ranged from 71.9 to 77.0 vol% for the sheep’s wool mat and 79.4 vol% for the coir mat at pF1. On all vegetation mats containing sheep’s wool, the overall impression of the perennials was better than in the control. Especially good were Asters. At the end of the trial, the assessment scores of Asters on the sheep’s wool mats were two scores higher than on the coir mat. Aster dumosus ‘Prof. Anton Kippenberg’ achieved an average plant height between 35.8, 35.8, and 36.5 cm on the sheep’s wool mats and 14.4 cm on the coir mat. Aster dumosus ‘Silberball’ yielded 41.3, 42.3, and 44 cm on the sheep’s wool mats and 26.7 cm on the coir mat. No significant differences regarding plant height between the different variants of sheep’s wool mats emerged. Therefore, these mats can be used as alternative planting concepts for landscaping. Full article

The main objective of this study is to use coconut husk to produce mortar for ferrocement. Mortar mix proportions are selected per ACI codes’ recommendation and the WRD Handbook. Four types of mortars: Cement and River Sand mortar (CSM), Cement, River Sand and Steel fibre mortar (CSSFM), Cement and Coconut Husk mortar (CCHM), and Cement, River Sand (60%), Coconut Husk (40%), and Steel fibre mortar (CSCHSFM) are used for this study Microstructural studies like SEM, EDX, XRD, and FTIR analysis on cement mortar constituents and mortar mixes are studied and reported. At 3, 7, and 28 days tests of hardened mortar, such as compressive, split tensile, flexural strength, and impact strength resistance, were studied. Test results revealed that the coconut husk is innovative and sustainable and could be an alternative fine aggregate that can be utilized in place of river sand, which in turn can be used for mortar production. Since it has a lesser density which proves to be an advantage for developing lightweight mortar, it can be used for ferrocement applications. Full article

Natural fiber-reinforced composites can contribute to reducing carbon footprint goals due to their ability to reduce overall product weight, bio-diverse feedstocks, and recyclability potential. In this work, natural fiber-based composites containing the reinforcement of coconut husk and bagasse fiber with calcium carbonate (CaCO₃) ingredients were prepared and analyzed. The composites were analyzed for mechanical, thermomechanical, and morphological properties. The reinforcements were chemically functionalized using 5% w/v NaOH to enhance their interactions with the epoxy resins. The chemical functionalization created perforation on the fiber surface, improving the interlocking of fibres with the resin material and strengthening the mechanical performance of the composite. The composites developed using modified reinforcement treatment resulted in increased tensile strength (64.8%) and flexural strength (70%). The reinforcement treatment influenced the hydrophilicity, and the water absorption of treated composites was reduced more than five times compared to the unmodified composites. Scanning electron microscopy revealed morphological changes due to fiber modification, the underlaying mechanism of fiber contraction, and enhanced fiber matrix interface interlocking and adhesion strengthening. Thermal analysis confirmed that alkali treatment improves the crystallinity of the fiber and thereto the degradation temperature of treated fiber composites (both bagasse and coconut husk), which is 375.27 °C, the highest amongst the developed hybrid composites. Full article

The treatment of greywater (GW, wastewater share excluding toilet flush) through green walls can be beneficial for urban areas, favouring the diffusion of urban vegetation and reducing potable water consumption. Multiple challenges hinder the treatment performance of green walls, including the composition of the filtering material, the number of levels—i.e., rows—and the age of the system. This study investigated graphene as an additive (5%v) to a filtering medium made of coconut fibre, perlite and biochar in an open-air green wall with pots arranged into three levels. The performance of GW treatment was quantified by comparing the physicochemical features of inflow and outflow samples collected weekly over two months. Samples were also collected at each level of the green wall, and the performance of two analogous systems different by age for three months were compared. The results showed that graphene did not significantly improve treatment performance, except for the first level (e.g., 48% vs. 15% for COD, 72% vs. 51% for TSS, with and without graphene respectively). Moreover, GW treatment mostly happened along the first two levels of the green wall, with marginal depletion (e.g., 15% vs. 7% for NH₄⁺-N) after three months of operational time. Full article

Raspberry fruits are a valuable source of bioactive compounds. The study used the modification of the substrate (coconut fibre), consisting of the use of various organic and mineral additives, in the soilless cultivation of raspberries. The additives influenced the biosynthesis of bioactive compounds in the raspberry fruits by modifying the sorption properties and the abundance of the substrate. The influence of the additives on the content of polyphenols was determined as well as their profile (UPLC-MS), antioxidant potential (ABTS), vitamin C content, and the activity of selected enzymes that are markers of stress and resistance to abiotic factors. In the study, a significant effect of these additives was observed on the biosynthesis of polyphenols in raspberry fruit. The highest increase in the content of these compounds in relation to the control sample (substrate—100% coconut fibre), namely 37.7%, was recorded in the case of fruit produced on coconut substrate enriched with sheep wool. These fruits were also characterised by a significantly different profile of these compounds. These changes were caused by readily available ammonium nitrogen and free amino acids in the decomposition of proteins contained in the sheep wool. This was confirmed by the recorded content of chlorophyll SPAD in the plant leaves and the activity of selected enzymes, which proves a low level of stress and good condition of the plants. Full article

Environmental conservation and waste control have informed and encouraged the use of biodegradable polymeric materials over synthetic non-biodegradable materials. It has been recognized that nano-sized biodegradable materials possess relatively good properties as compared to conventional micron-sized materials. However, the strength characteristics of these materials are inferior to fossil-based non-biodegradable materials. In this study, biodegradable polylactide (PLA), reinforced with treated coconut husk particulates (CCP) for improved mechanical properties, was fabricated using an electrospinning process and representative volume element (RVE) technique, and some of the obtained mechanical properties were compared. It was observed that the electrospun CCP-PLA nanofibre composites show improved mechanical properties, and some of these mechanical properties using both techniques compared favourably well. The electrospun fibres demonstrate superior properties, mostly at 4 wt.% reinforcement. Thus, achieving good mechanical properties utilising agro waste as reinforcement in PLA to manufacture nanocomposite materials by electrospinning method is feasible and provides insight into the development of biodegradable nanocomposite materials. Full article

To offer a viable alternative to seedling deployment of tea tree, clones will require the development of an efficient, robust, and vegetative propagation system for the large number of plants needed for plantations (i.e., typically 33,000 plants/ha). This study investigated the productivity of an intensive management system for tea tree stock plants and rooted cuttings grown in a subtropical environment (Lismore, NSW, Australia). Three stock plant densities (30, 100, and 200 plants/m²) were tested in coir and potting mix media (consisting of peat+perlite+vermiculite), with 11 settings of cuttings undertaken between April 2019 and March 2020. All stock plants in each media type survived 11 harvests and remained productive; however after 13 months, many plants in the coir media, appeared chlorotic and showed symptoms of iron deficiency. Rooting and cutting survival rates using the mini cutting technique were high, ranging from a maximum mean monthly setting value of 87.7% ± 4 at 84 days post-setting in potting mix, to a minimum of 80.4% ± 3.7 in coir. The most productive treatment was at high stock plant density in potting mix which had the potential to produce 13,440 plants/year/m². Overall coir appeared less productive, but the pattern of difference among treatments was similar. For the highest system productivity, it is recommended to grow stock plants in potting mix at high densities and modulate temperatures to between 18 °C and 28 °C. Late spring and early summer were the best time for harvesting and setting tea tree mini cuttings in the subtropics. Full article

Globally, as human population and industries grow, so does the creation of agricultural, industrial, and demolition waste. When these wastes are not properly recycled, reused, or disposed of, they pose a threat to the environment. The importance of this study lies in the beneficial use of coconut fibre and mineral wool in the form of fibres in cement mortar production. This study examines the use of coconut and mineral wool fibres in the production of fibre-reinforced mortar. Five different mortar mixtures were prepared, having one control mortar along with four fibre-reinforced mortars. The control mortar is denoted as CM while 1% and 1.5% of mineral wool are incorporated into this mortar mix and denoted as RMM-1.0 and RMM-1.5, respectively. Additionally, the mortar sample configurations contain 1% and 1.5% coconut fibers, designated as RCM-1.0 and RCM-1.5. These samples were subjected to different strength and durability tests to determine their suitability for use in mortar production. The testing findings show that mortar containing 1.5% mineral wool has better compared flexural strength and durability properties. The investigation results will form part of the database for the efficient utilization of natural and waste fibres in the construction and building sectors. Full article

Hybrid glass fibre reinforced polymer (GFRP) composites have been used for decades in various engineering applications. However, it has a drawback with its application in marine/flood environments due to a lack of water resistance and frail mechanical stability. Floods have been considered one of the most periodic hazards that could hit urban areas, due to climate change. The present paper aims to address this gap and to investigate the mechanical properties (tensile, compressive, and flexural strength) and water absorption capacity of hybrid GFRP composite comprising woven E-glass fabric and epoxy resin, various reinforcing materials (kenaf and coconut fibres), and various filler materials (fly ash, nano-silica, and calcium carbonate (CaCO₃). The composites with 30 wt.% GFRP, 50 wt.% resin, 15 wt.% fly ash, 5 wt.% CaCO₃, 10 wt.% GFRP, 60 wt.% resin, and 30 wt.% fly ash showed the lowest water absorption property of 0.45%. The results revealed that the GFRP composite reinforced kenaf fibres with nano-silica, fly ash, and CaCO₃ improved the water absorption resistance. At the same time, GFRP reinforced the coconut fibres with fly ash, and kenaf fibres with CaCO₃ showed no favourable impact on water absorption. The identification of a hybrid GFRP composite with various reinforcing materials and fillers would assist future developments with a more compatible, enhanced, and reliable water-resistant composite, specifically for structural applications in flood-prone areas. Full article

Natural fibre-reinforced cementitious composites are commonly used as outer construction materials. They usually suffer weather as a result of being expose to various types of climates. In this study, a series of experimental tests were carried out to investigate the deterioration mechanism and mechanical properties of mortars incorporating coconut fibres due to repeated wetting and drying. The results indicated that although the compressive strength was found to increase after the first cycle, both compressive and flexural strengths underwent a significant decrease in the fifth cycle. In addition, at high temperatures, mortar matrixes retain their stable structure, according to the results of TGA analysis. When wetting and drying curing was applied, there was a significant degradation of fibres in the mortar. Full article