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<b>Background and Objective:</b> Organic fertilizer is a source of nutrition for plants which is an alternative to inorganic fertilizer. Liquid organic fertilizer (LOF) which comes from coconut fiber and banana LOF which comes from banana stems from which the fruit has been removed, so that wasted plant residue can be used as fertilizer. The study aimed to obtain the best type of LOF and concentration in increasing the growth and yield of the Batang Piaman rice variety using the SRI method. <b>Materials and Methods:</b> The research was conducted from June to December, 2023 in Padang City, West Sumatra. The method used was an experiment with a Randomized Complete Block Design (RCBD) in nested with each treatment consisting of 3 groups. The treatment consisted of LOF types at two levels (banana stems and coconut fiber) and LOF concentrations at seven levels (0, 50, 100, 150, 200, 250 and 300 mL/L). Observational data were analysed by variance analysis with F test at 5% real level, but if there were differences, it was continued with DMRT further test at 5% real level by STAR IRRI Philippine software (Philippine). <b>Results:</b> The results obtained were that LOF coconut fiber provided better growth components, yield components and physiological components than banana stem LOF with the best concentration, on the provision of LOF coconut fiber 100 mL/L on the number of rice plant tillers and stomatal density and concentration of 200 mL/L on the number of productive tillers. <b>Conclusion:</b> The application of LOF coconut fiber is better for the growth and yield of rice plants of the Batang Piaman variety compared to the administration of LOF banana stems by applying coconut fiber liquid organic fertilizer with a concentration of 100 mL/L, it is recommended to add coconut fiber LOF to rice fields to increase growth and yield.

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With the development of the technical trend, concrete using waste alternate material instead of sand material found economic potential for good structural behaviour. Besides, the susceptible crack, low strength-to-weight ratio, and low compressive strength are the reasons for shrinkage. Due to this reason, the investigation aims to limit the shrinkage under live load and increase the compression and flexural strength by the introduction of coconut waste chopped fiber (wCF), waste fly ash (wFA), and carbon nanotube powder (CNT) blended with conventional Portland paste. The developed concrete consists of 5 wt% wCF, 10 wt% wFA, and 0, 5, 10, and 15 wt% of CNT and is subjected to X-ray diffraction analysis, bulk density, compression and flexural strength, and water absorption studies. The X-ray diffraction pattern revealed the wCF, wFA, CNT, and matrix compositions. The concrete developed with 5 wt% wCF, 10 wt% wFA, and 15 wt% CNT cured within 28 days recorded maximum behaviour of compression strength (47 ± 1.8 MPa), flexural strength (4.9 ± 0.19 MPa), and water absorption of (2.8 ± 0.05 %).

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Constructed wetlands (CWs), crucial for the rural decentralized wastewater treatment, have encountered limitations in nutrient removal efficiency and require extensive land area. This study has constructed a novel overlapping horizontal subsurface flow CWs (OLCWs). Remarkably, OLCWs with mixed lightweight fillers (M-OLCWs) exhibited a significant enhancement in total nitrogen (TN) removal efficiency (88-91 %) in different hydraulic loading rates compared to single filler OLCWs (48-62 %). This significant enhancement can be attributed to the lightweight fillers, which have higher abundances and diversity of nitrogen related microorganisms. The treatment dynamics revealed that the second stage exhibited an excellent TN removal efficiency (73-75 %) attributed to sufficient dissolved oxygen concentration by water drops reoxygenation. The research reveals that M-OLCWs, by utilizing water drops reoxygenation and lightweight fillers, not only enhance pollutant treatment efficiency but also reduce required land area, thereby offering a sustainable solution for rural decentralized wastewater treatment.

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The use of natural fibers in cementitious composites has been gaining prominence in engineering. The natural lignocellulosic fibers (NLFs) used in these composites have advantages such as reduced density, reduced fragmentation and concrete cracking, thus improving flexural performance and durability. Coconut-fiber is one of those natural fibers and its use presents technical, ecological, social and economic benefits, as it is improperly disposed of, representing a large waste of natural resources, in addition to causing environmental pollution.. Thus, composites reinforced with natural fibers are promising materials for the construction industry, as in addition to meeting the sustainability of buildings, there will also be a reduction in urban solid waste generated and gains for structures with the use of environmentally friendly materials that meet to active efforts and with greater durability. This work aims to evaluate the tensile behavior of green coconut-fibers subjected to different drying temperatures through chemical, thermal (TG/DSC), morphological, visual and mechanical analysis. Drying temperatures of 70 °C, 100 °C and 130 °C were analyzed and the results indicated that the drying temperature at 70 °C was satisfactory, providing fiber-reinforced composites with good tensile strength, combined with good ductility.

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The incorporation of coconut fiber (CF) into magnesium phosphate cement (MPC) can effectively improve upon its high brittleness and ease of cracking. In practical engineering, coconut fiber-reinforced magnesium phosphate cement (CF-MPC) will likely work in cold environments. Therefore, it is essential to understand the effects of various types of low-temperature curing on CF-MPC performances, but there are very few studies in this area. In this study, the static compression and three-point bending test were utilized to examine the compressive and flexural characteristics of CF-MPC with various CF contents and different negative curing temperatures. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) were conducted to observe the impact of low-temperature maintenance on the structure and hydration reaction of the specimens. The results indicate that CF-MPC curing at low temperatures was more prone to cracks during compression and bending, while the appropriate amount of CF could enhance its plastic deformation capability. The CF-MPC's compressive and flexural strength declined as the curing temperature dropped. Moreover, with the rise in CF content, the samples' compressive strength also tended to fall, and there was a critical point for the change in flexural strength. In addition, MPC's primary hydration product (MgKPO4·6H2O) decreased with a drop in curing temperature, and more holes and fractures appeared in CF-MPC.

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In developing countries like India, an economically viable and ecologically approachable strategy is required to safeguard the drinking water. Excessive fluoride intake through drinking water can lead to dental fluorosis, skeletal fluorosis, or both. The present study has been under with an objective to investigate the feasibility of using cellulose derived from coconut fiber as an adsorbent under varying pH conditions for fluoride elimination from water. The assessment of equilibrium concentration of metal ions using adsorption isotherms is an integral part of the study. This present finding indicates the considerable effect of variation of adsorbent dosages on the fluoride removal efficiency under constant temperature conditions of 25 ± 2 °C with a contact period of 24 h. It is pertinent to mention that maximum adsorption of 88% has been observed with a pH value of 6 with 6 h time duration with fluoride dosage of 50 mg/L. The equilibrium concentration dwindled to 0.4 mg/L at fluoride concentration of 20 mg/L. The Langmuir model designates the adsorption capacity value of 2.15 mg/L with initial fluoride concentration of 0.21 mg/g with R2 value of 0.660. Similarly, the adsorption capacity using Freundlich isotherms is found to be 0.58 L/g and 0.59 L/g with fluoride concentration of 1.84 mg/L and 2.15 mg/L respectively. The results from the present study confirm that coconut fiber possesses appropriate sorption capabilities of fluoride ion but is a pH dependent phenomenon. The outcomes of the study indicate the possible use of cellulose extracted from waste coconut fiber as a low-cost fluoride adsorbent. The present study can be well implemented on real scale systems as it will be beneficial economically as well as environmentally.

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In agricultural countries, Agro-industrial residues are better treated with a circular production logic. This article analyzes the morphological, physical, mechanical, thermal, and chemical characteristics of the coconut fiber and endocarp in Portoviejo and Rocafuerte Cities, Ecuador, to establish a baseline of knowledge that can help to incorporate coconut residues into a matrix of a new material. Interviews were conducted to coconut producers in Portoviejo and Rocafuerte and a random sample of the residues was collected from these locations. Analyses were performed using the SEM, TGA and FRX tests. Concerning the fiber, it was observed a tubular morphology with concentric microfibrils, specific weight 0.69 g/cm3, tensile strength 228 MPa, modulus of elasticity 3.03 GPa, thermal behavior with important mass losses at 330 °C, in the calcinations to obtain oxides as SiO2, SO3, Al2O3, Fe2O3 at 600 °C and 650 °C. The endocarp has a morphology of superimposed and consolidated smooth layers, specific weight 1.29 g/cm3, loss of mass at 339 °C and in calcinations at 800 °C. This study can help to address solid vegetable waste managing challenges in coconut producing cities.

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The lignin valorization constitutes a chemical platform for several segments of chemical industry. The aim of this work was to evaluate the potential of acetosolv coconut fiber lignin (ACFL) as an additive to DGEBA, curing it using an aprotic IL ([BMIM][PF6]) and analyze the properties of the obtained thermosetting materials. ACFL was obtained by mixing coconut fiber with 90 % acetic acid and 2 % HCl at 110 °C during 1 h. ACFL was characterized by FTIR, TGA and 1H NMR. The formulations were fabricated by mixing DGEBA and ACFL at different concentrations (0-50 % wt.). The curing parameters and [BMIM][PF6] concentrations were optimized by DSC analyses. The cured ACFL-incorporated epoxy resins were characterized by gel content (GC), TGA, MCC and chemical resistance in different media. ACFL undergone a selective partial acetylation that favored its miscibility with DGEBA. High GC values were obtained at high curing temperatures and ACFL concentration. The crescent ACFL concentration did not affect the Tonset of the thermosetting materials significantly. ACFL has increased the resistance of DGEBA to combustion and different chemical media. ACFL has shown a great potential to be used as a bio-additive for enhancing the chemical, thermal and combustion properties of high-performance materials.

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Pollution due to various heavy metals is increasing at an alarming rate. Removal of hexavalent chromium from the environment is a significant and challenging issue due to its toxic effects on the ecosystem. Development of a low-cost adsorbent with better adsorption efficiency is presently required. In this study, waste coconut fibers (CF) were used to prepare its composite with polyaniline (PANI) via in-situ oxidation. The obtained composites with varying loading of PANI (15, 25, 50, and 75% w/w) were characterized by FE-SEM, TGA, and FTIR spectroscopy. The prepared composites were evaluated for their adsorption performance for removal of Cr(VI). It was concluded that the composite with 50% w/w polyaniline loading on coconut fiber exhibited a maximum adsorption efficiency of 93.11% in 30 min. The effect of pH, dosage, and concentration of the aqueous solution of chromium on the Cr(VI) adsorption efficiency of the composite was also studied. From the optimization studies it was observed that the absorbents exhibited the best adsorption response for Cr(VI) removal with 0.25 mg/mL adsorbent at pH 4, in 30 min. The effect of pH, dosage, and concentration of the aqueous solution of chromium on the Cr(VI) adsorption efficiency of the composite was also studied. This study highlights the application of low-cost adsorbent as a potential candidate for the removal of hexavalent chromium. A detailed study on the adsorption kinetics and isothermal analysis was conducted for the removal of Cr(VI) from aqueous solution using coconut fiber-polyaniline composite. From the kinetic investigation, the adsorption was found to follow the pseudo second order model. The data obtained were best fitted to the Elovich model confirming the chemisorption of the Cr(VI) on coconut polymer composites. The analysis of the isothermal models indicated monolayer adsorption based on the Langmuir adsorption model.

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Biodegradable materials are appropriate for the environment and are gaining immense attention worldwide. The mechanical properties (such as elongation at break, density, and failure strain) of some natural fibers (such as Coir, Hemp, Jute, Ramie, and Sisal) are comparable with those of some synthetic fibers (such as E glass, aramid, or Kevlar). However, the toughness of coconut fibers is comparatively more than other natural fibers. Numerous studies suggest coconut fibers perform better to improve the concrete mechanical properties. However, the knowledge is dispersed, making it difficult for anyone to evaluate the compatibility of coconut fibers in concrete. This study aims to perform a scientometric review of coconut fiber applications in cementitious concrete to discover the various aspects of the literature. The typical conventional review studies are somehow limited in terms of their capacity for linking different literature elements entirely and precisely. Science mapping, co-occurrence, and co-citation are among a few primary challenging points in research at advanced levels. The highly innovative authors/researchers famous for citations, the sources having the highest number of articles, domains that are actively involved, and co-occurrences of keywords in the research on coconut-fiber-reinforced cementitious concrete are explored during the analysis. The bibliometric database with 235 published research studies, which are taken from the Scopus dataset, are analyzed using the VOSviewer application. This research will assist researchers in the development of joint ventures in addition to sharing novel approaches and ideas with the help of a statistical and graphical description of researchers and countries/regions that are contributing. In addition, the applicability of coconut fiber in concrete is explored for mechanical properties considering the literature, and this will benefit new researchers for its use in concrete.

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This study presents the fresh and mechanical properties of concrete made with recycled aggregates (RAs) and coconut fibers (CFs), with an emphasis on the development of sustainable and ductile cementitious composite through the valorization of coconut and construction wastes. For this purpose, the effect of different percentages of CF, i.e., 0%, 1%, 2%, and 3% by wt. of cement, was examined on the mechanical and physical properties of concrete incorporating RA (0%, 30%, 50%, and 100%). To avoid the negative effect of CF on workability, a plasticizer was used to achieve the target workability. The performance of mixes was evaluated based on the results of workability, density, compressive strength (CS), splitting-tensile strength (STS), flexural strength (FS), and water absorption. The results showed that incorporation of 1-2% CF improved the CS and STS of concrete for each constant level of RA. The addition of 2% CF is recommended for maximum mechanical performance. Concrete incorporating 50% coarse RA with 2% CF showed CS comparable to conventional concrete. Concrete made with 100% coarse RA and 2% CF showed STS and FS comparable to that of conventional concrete. This study recommends the use of 2% CF along with plasticizer to attain the best mechanical performance. Despite comparable STS and FS, 100% RA concrete with 2% CF produced 25% lower CO2 emissions than conventional concrete.

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The caffeine adsorptive performance and compatibility characteristics (Eisenia foetida Savigny) of rice husk, peanut shell, corn cob and coconut fiber were studied, aiming to assess the suitability of these residues for vermifilter beds. For this purpose, the agro-industrial residues were characterized and the E. foetida Savigny compatibility was determined by acute and chronic toxicity tests. Batch adsorption tests were performed using caffeine solutions. Optimal adsorption conditions, kinetic models, isotherm type and the influence of three particle sizes (120-150, 300-600, 800-2000 µm) in the caffeine removal were determined. Coconut fiber (120-150 µm) proved to be the most efficient residue for the caffeine removal (94.2%), requiring 4 g/L for 30 min. However, coconut fiber was the less compatible for earthworms (14d-LC50 = 82%). The results obtained allow to define adequate strategies, such as mixing highly adsorptive residues with the more compatible ones, to choose the most effective materials for vermifiltration technologies.

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The present study illustrates enhanced removal of methylene blue (MB) and malachite green (MG) from water using alkali-activated coconut fiber (ACF) as adsorbent. Alkali activation effectively reduces the lignocellulosic components present within coco-fiber which in turn reinforces the coco-fiber to become more water-stable. The material was characterized by FTIR, SEM-EDS, BET, XRD, and pHZPC. BET surface area was found to be 10.901 m2 g-1, whereas pHZPC of the material is 6.05. FESEM images reveal rod-like morphology. Batch experiments were optimized with respect to contact time (0-120 min), temperature (288-308 K), pH (3-10), dose (1-5 g) and input dye concentration (10-50 mg L-1). The maximum adsorption coefficient was found to be 133.11 and 110.74 mg g-1 for MB and MG respectively. Adsorptions are best described by pseudo-second-order kinetics (kMB = 1.712, R2 = 0.999; kMG = 1.399, R2 = 0.999) and Langmuir isotherm model (R2 = 0.999). Thermodynamic data suggests a spontaneous (ΔG, -14 kJ mol-1) and feasible process. Spent material could be regenerated by using 0.5 M HCl. Up to 50% retention of activities was seen after five cycles. It can be concluded that alkali-activated coconut fiber is an economic and sustainable choice for dye removal. Novelty statement: Spent coconut was converted into an effective biosorbent by simple alkali activation under ambient conditions to increase the hydrophobicity of the fibers by reducing the lignocellulosic components. Two cationic dyes; methylene blue and malachite green have been efficiently removed with adsorption capacities of 133.11 and 110.74 mg g-1. The operation is simple, economically viable, and partially fulfills the principles of green engineering. Comparing with contemporary adsorbents, this material offers higher adsorption capacities with multi-cycle reusability and enhanced water stability.

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To decrease the amount of waste biomass and develop a useful application. Coconut fiber (CF) was used to prepare a novel adsorbent to remove methylene blue (MB), which is a recalcitrant organic compound in the water environment. We were able to produce novel adsorbents such as CCF500 and CCF1000 by the calcination treatment of CF. The specific surface area and pore volume of CCF1000 were higher than those of CF or CCF500. Quantity of MB adsorbed was in the order; CCF5000.986). The adsorption mechanism of MB using CCF1000 was demonstrated in this study. The intensities of carbon (C), nitrogen (N), and sulfur (S) onto CCF1000 surface increased after adsorption of MB. In addition, the binding energies of nitrogen (1s) at approximately 400 eV and sulfur (2s and 2p) at approximately 165 and 230 eV which were generated after adsorption. Therefore, the adsorption of MB from aquatic solution was strongly involved with the physicochemical properties of CCF1000 surface. Our findings showed that CCF500 and CCF1000 could be produced from CF by calcination treatment, which demonstrates that the amount of waste biomass decreased. In particular, CCF1000 displays the capability to adsorb MB from aquatic solution. These results showed that CCF1000 could be a useful adsorbent for aquatic environment purification.

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Comprehensive two-dimensional gas chromatography coupled with time-of-flight mass spectrometry (GC × GC/TOFMS) is used to characterize complex bio-oil samples because of the high peak capacity associated with the high acquisition rate and mass spectra deconvolution capability of TOFMS. A recent application of fast GC × GC for this type of analysis improved sample throughput while achieving the same peak capacity without the use of cryogenic liquids. This work evaluates the effect of the TOFMS data acquisition rate on the quality of the analytical information obtained by GC × GC/TOFMS. In the analysis of coconut fiber bio-oil under fast GC × GC/TOFMS conditions, use of high data acquisition rates (200-300 Hz) increases the number of identifiable peaks by more than 50% compared with that achieved at the conventional rate of 100 Hz. The acquisition rate can affect the peak capacity by a factor of 3 or more. This is the first study to demonstrate the importance of optimizing the data acquisition rate, a parameter that has previously been neglected in the literature, in GC × GC/TOFMS development.

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The work assumed the possibility of the introduction natural fibers as a hybrid reinforcement of bio-polyethylene composites. Coconut fibers, basalt fibers and wood flour were used in different combination as a hybrid merger. Mechanical tests were conducted. An increase in the mechanical properties was shown as an effect of the introduction of the fibers info the polymeric matrix. A synergic influence of hybrid reinforcement was also presented. Experimental results were compared with modeling parameters. The hydrothermal and accelerated thermal ageing effects on the mechanical behavior of composites were presented. Scanning electron microscope images were observed in order to analyze structure of examined composites.

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Recently, the addition of natural fibers to high strength concrete (HSC) has been of great interest in the field of construction materials. Compared to artificial fibers, natural fibers are cheap and locally available. Among all natural fibers, coconut fibers have the greatest known toughness. In this work, the mechanical properties of coconut fiber reinforced high strength concrete (CFR-HSC) are explored. Silica fume (10% by mass) and super plasticizer (1% by mass) are also added to the CFR-HSC. The influence of 25 mm-, 50 mm-, and 75 mm-long coconut fibers and 0.5%, 1%, 1.5%, and 2% contents by mass is investigated. The microstructure of CFR-HSC is studied using scanning electron microscopy (SEM). The experimental results revealed that CFR-HSC has improved compressive, splitting-tensile, and flexural strengths, and energy absorption and toughness indices compared to HSC. The overall best results are obtained for the CFR-HSC having 50 mm long coconut fibers with 1.5% content by cement mass.

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BACKGROUND: Organic soilless production in containers requires substrates with appropriate physicochemical and biological properties to ensure that production is sustainable and profitable for several production cycles. The main objective of this study was to comprehensively evaluate these properties in three different mixtures of organic substrates (vermicompost [V] and coconut fibers [CF] in ratios 20V80CF, 40V60CF, 60V40CF) for four horticultural crop production cycles (PCs) using vermicompost tea (VT) as the main source of nutrients. RESULTS: Readily available water (25%) in the control treatment (20V80CF) was below the recommended limit, and dry bulk density (>450 g/L) surpassed the recommended limit in the 60V40CF treatment (p < 0.05). In terms of chemical properties, cations and anions in the saturated media extract decreased significantly to values below established optimal conditions. Furthermore, the substrates presented high enzymatic activity in successive production cycles (p < 0.05), including dehydrogenase (350-400 µg TFF g-1), acid phosphatase (4,700 µg p-nitrophenol g-1 soil hr-1), and ß-glucosidase (1,200 µg p-nitrophenol g-1 soil hr-1) activity during transformation from organic matter to inorganic compounds. CONCLUSION: The 40V60CF treatment presents adequate physicochemical and biological characteristics for reuse for more than four growing cycles when organic supplements are administered.

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Coconut shell concrete is one of the recently established lightweight concretes. This paper discusses the optimization of adding coconut fibers in both coconut shell concrete and conventional concrete. Coconut fibers at different aspect ratios of 16.67, 33.33, 50, 66.67, 83.33, and 100 and volume fractions of 1, 2, 3, 4, and 5% were tried. The maximum compressive strength was attained at an aspect ratio of 83.33 and volume fraction of 3% for conventional concrete, and aspect ratio 66.67 and volume fraction 3% for coconut shell concrete. Flexural strength increased by 30.63% (conventional concrete) and 53.66% (coconut shell concrete) on the addition of coconut fibers. Similarly, the split tensile strength increased by 19.44% and 30%, respectively. The number of blows needed for failure of specimen in impact resistance test was more for concrete mixed with fibers. The experimental bond stresses were higher than the theoretical values recommended by IS 456: 2000 (Indian Standard) and BS 8110 (British Standard). This study shows that the addition of coconut fiber enhances the properties of both conventional and coconut shell concrete.

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RESUMO Os processos de adsorção podem ser empregados no tratamento de efluentes líquidos contendo metais pesados visando a reduzir os danos ambientais. Porém, o alto custo dos materiais adsorventes justifica a aplicação de adsorventes alternativos, como a fibra de coco (FC) e a quitosana (Q). Assim, este trabalho teve como objetivo desenvolver compósitos porosos adsorventes a partir da mistura de polietileno graftizado com anidrido maleico/FC/Q/NaCl, como agente porogênico (PE-g-MA/FC/Q/NaCl), e avaliar estatisticamente a capacidade de adsorção do cromo (III) em solução, com auxílio do software Statistica 5.0®. Os resultados mostraram que a eficiência do processo sofreu influência das dimensões da FC, do teor de Q e do pH da solução contendo Cr (III). A capacidade máxima de remoção de Cr (III) por unidade de massa do compósito foi de 42,28 mg.g-1.

ABSTRACT Adsorption processes can be employed in the treatment of wastewater containing heavy metals to reduce environmental damage. However, the high cost of adsorbent materials justifies the application of alternative adsorbents, such as coconut fiber (CF) and chitosan (C). Thus, this study aimed to develop porous composite adsorbents from the mixture of grafted maleic anhydride polyethylene/CF/C/NaCl, as porogen agent (PE-g-MA/CF/C/NaCl), and evaluate statistically adsorption capacity of chromium (III) solution, with the aid of software Statistica 5.0®. The results showed that the process efficiency was influenced by the size of the CF, the content of C and the pH of the solution containing Cr (III). The maximum removal capacity of Cr (III) per unit mass of the composite was 42.28 mg.g-1.