Water Absorbency Properties of OPEFB Filled Hydrogels Composites

2014 ◽  
Vol 980 ◽  
pp. 18-22
Author(s):  
Nurul Ekmi Rabat ◽  
Shahrir Hashim ◽  
Rohah A. Majid

For slow release fertilizer application, oil palm empty fruit bunch-grafted-poly (acrylic acid-co-acrylamide) [OPEFB-g-P(AA-co-AAm)] hydrogel composites were synthesized via two techniques; Two Steps (T1) and in-situ (T2). Scanning electron microscopy of hydrogel composite T1 has higher surface area and holes while hydrogel T2 displays smoother and tighter surface. Water absorbency capacity of hydrogel T1 is 42.90 gram/gram (g/g) and hydrogel T2 is 39.96 g/g. WAC of hydrogel T2 has much better re-swelling ability compared to T1 after it went through five cycles of drying-swelling-drying process. Hence, T2 has produced a hydrogel composite that is reusable with great morphology properties.

2019 ◽  
Vol 15 (1) ◽  
pp. 112
Author(s):  
Syahiful Hadi ◽  
Suryajaya Suryajaya ◽  
Abdullah Abdullah ◽  
Kissinger Kissinger

Urea-hydroxyapatite can be used as fertilizer which was efficient and environmentally friendly. The variation of Ca(OH)2 in the urea-hydroxyapatite’s synthesis and its characterization would provide information for manufacturing slow release fertilizer. The material used were urea (99.5 %); Ca(OH)2; H3PO4 0.67 M and distilled water. The synthesis technique used in this study is bottom-up with Ca(OH)2 variation of 6, 8, 10 and 12 grams. The results of the synthesis with 6 grams of Ca(OH)2  was not able to produce sediment powder. The results of the Scanning Electron Microscopy (SEM) showed that the urea packaging with hydroxyapatite was better for variations of Ca(OH)2  8 grams and 10 grams. The results of the Energy Dispersive X-Ray Spectrometry (EDX) showed more elemental composition in the variation of Ca(OH)2  8 grams and 10 grams which were 35.7 Wt% and 40.4 Wt%. The results of the Fourier Transform Infrared Spectrometer (FTIR) showed that the variation of Ca(OH)2  8 gram has a good bonding of urea and hydroxyapatite. The Particle Size Analyzer (PSA) measurement for all samples of urea-hydroxyapatite yielded the particle size of about 0.5–2.5 mm and 10–15 mm for urea and hydroxyapatite, respectively. As a conclusion, the variation of Ca(OH)2  8 grams could be recommended as a reference in the composition of urea-hydroxyapatite fabrication for slow release fertilizer.


2021 ◽  
Vol 889 ◽  
pp. 91-97
Author(s):  
Suntree Sangjan ◽  
Wadchara Thongsamer

A novel slow-release N-fertilizer hydrogel beads were developed using sodium alginate (SA) and alginate-talcum (ST) composite as N-absorbent. In this work, the hydrogel composite were fabricated by simple method and low cost. N-fertilizer hydrogel beads were prepared two types, for SA types, which were different sodium alginate (1(SA1), 3(SA3), 5(SA5), 7(SA7), and 10(SA10) wt%). And, for ST types, sodium alginate and talcum were vary ratios to 1:0.5(S1T0.5), 1:1(S1T1), and 1:2 (S1T2). The chemical structure of hydrogel composite beads were characterized via Fourier transform infrared spectroscopy (FT-IR) and X-ray diffraction (XRD). The release behavior were investigate by Zero-order kinetic model, First-order kinetic model, Higuchi model and Korsmeyer-Peppas model. We have found that the N-fertilizer release constants in Korsmeyer-Peppas model were decrease with increase SA content for 1-5 wt% in SA hydrogel beads. However, SA contents were more than 5 wt% which rapidly enhanced fertilizer release. In addition, to add talcum in ST hydrogel beads significantly reduced fertilizer release rate. The N-fertilizer hydrogel beads exhibits significantly slow release behavior. These results indicates that the development of slow-release fertilizer hydrogel beads can be improve the effectiveness of N-fertilizer.


2012 ◽  
Vol 557-559 ◽  
pp. 139-142
Author(s):  
Jian Guo Liu ◽  
Yan Tao Li ◽  
Bao Rong Hou

The corrosion processes and mechanisms of Q235A steel under wet-dry cyclic condition were studied using polarization curve compared with immersion samples, while, the corrosion morphologies and corrosion products of the steel samples were characterized using scanning electron microscopy (SEM) and X-ray diffraction (XRD). The cathodic process of wet-dry samples was likely to be controlled not by the oxygen reduction, but rather by the reduction of corrosion products. During the drying process of the wet-dry sample, the electrolyte thickness decreased and chloride concentration increased. Oxygen would be much easier to diffuse into the interface of electrolyte/metal, which improved the cathodic reduction processes. Except for this, the rust itself took part in the reduction processes and hence increased the corrosion rate of the steel samples.


2011 ◽  
Vol 194-196 ◽  
pp. 389-392
Author(s):  
Ling Li ◽  
Hong Liang Li ◽  
Ying Chun Zhu ◽  
Ai Ping Fu ◽  
Yong Wan ◽  
...  

Polystyrene (PS) spheres encapsulated core-shell composites of SiO2or TiO2nanoparticles were prepared by the spray drying technique and hollow spheres of SiO2or TiO2nanoparticles were then derived by removing the PS cores with calcinations. The PS spheres were dispersed into the SiO2or TiO2colloids, forming a suspension and then the suspensions were sprayed to form micrometer-sized droplets, as the droplets rush through the drying chamber, the PS spheres were encapsulated into the core of SiO2or TiO2particles due to the high temperatures and the instant evaporation, obtaining PS@SiO2, PS@TiO2or PS@SiO2/TiO2core-shell composites. After removing the PS core by calcination at 550°C, SiO2or TiO2hollow spheres were then derived. The influence of drying temperature, the concentration of the SiO2or TiO2particles and the ratio of PS sphere to the particles on the structures and specific surface area of the hollow spheres were studied with scanning electron microscopy (SEM) and nitrogen adsorption-desorption measurements.


2012 ◽  
Vol 1498 ◽  
pp. 9-14 ◽  
Author(s):  
Ana Paula V. Araújo ◽  
Claure N. Lunardi ◽  
Anderson J. Gomes

ABSTRACTMethotrexate (MTX), is a potent immunomodulating drug and widely used in the treatment of cancer, psoriasis and others disease. Despite its efficacy, the use of MTX is greatly limited due to its toxicity. To solve this problem, we prepared nanoparticles of tetraethyl orthosilicate (NP-TEOS) containing the compound methotrexate (MTX), by the sol-gel method. This drug delivery system (DDS) showed a loading efficiency of 39.7%. Size distribution studies were performed with dynamic light scattering and scanning electron microscopy revealing that these particles were spherical in shape, with a mean diameter between 140-430 nm and a low polydispersity (0.12 – 0.26). Also the particles displayed a low tendency toward aggregation which was confirmed by the low zeta potential -61.4 mV. Profile release showed a slow release loaded with MTX (PBS buffer pH = 7.4). The slow release can be attributed to the low porosity of the NP-TEOS and the extremely low diffusivity of MTX in aqueous media. B16-F10 cells were used to assay the toxicity and uptake of NP-TEOS showing to be nontoxic without MTX making a good candidate for DDS.


2016 ◽  
Vol 20 (1) ◽  
pp. 37 ◽  
Author(s):  
Lili Handayani ◽  
Gunawan Djajakirana ◽  
. Darmawan ◽  
Canecio Peralta Munoz

The low-efficiency problem in fertilizer application can be overcome by controlling fertilizer solubility, i.e. by rendering the fertilizer to be released gradually; such material is also known as slow-release fertilizer (SRF). This research was aimed to formulate SRF by coating technique using acrylic and chitosan as the coating material, and to evaluate fertilizer resistance to too fast disintegration, and rate of nutrient release method. The results demonstrated that fertilizer formulation containing  N, P, K, Fe, Cu, and Zn with granulation technique yielded 74% of granules with 2-5 mm in diameter. The SRFs (formulated fertilizer with acrylic or chitosan coating) were more resistant to water pounding than non-SRF. Furthermore, shaking test with distilled water or 2% citric acid, or by percolation test with distilled water showed that the SRFs had lower nutrient solubility than the non-SRFs. The results of shaking test also specifically indicated that coating with acrylic made the fertilizer more resistant to the citric acid,suggesting that this coating material would be more suitable in acidic soils. The SRFs formulated with the addition of chitosan during blending of micronutrients prior to mixing with macronutrients, granulation, and final coating exhibited lower nutrient solubility than the SRFs without the pre-coating chitosan addition. [How to Cite: Lili H, G Djajakirana, Darmawan, and CP Munoz. 2015. Slow- Release Fertilizer Formulation Using Acrylic and Chitosan Coating. J Trop Soils 19: 37-45. Doi: 10.5400/jts.2015.20.1.37][Permalink/DOI: www.dx.doi.org/10.5400/jts.2015.20.1.37]


2020 ◽  
Vol 31 (1) ◽  
pp. 9-13
Author(s):  
Aliyu Danmusa Mohammed ◽  
Yusuf Hassan

AbstractStarch is acryloylated and copolymerised without incorporating any vinyl monomer such as acrylic acid or acrylonitrile monomers to produce a superabsorbent copolymer. Fenton’s initiation system was used to produce polyacryloylated starch ester with varying degree of substitution. The copolymer from starch ester exhibited improved solubility, and an impressive water, saline, and solvents uptake. The superabsorbency of the samples is affected by the number of acryloyl groups on starch backbone. The starch ester with degree of substitution 0.8 had the highest water absorbency (102 g/g) in this experiment. Fourier-transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and thermogravimetric (TGA) analyses were used to characterize the products.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Leila Javazmi ◽  
Tobias Low ◽  
Gavin Ash ◽  
Anthony Young

AbstractUrea is the most common form of nitrogenous fertiliser. Recently, research has focused on the development of delivery systems to prolong fertiliser release and prevent fertiliser loss through leaching and volatilization. This study investigates and compares single- and double-layered hollow nanofibrous yarns as novel delivery systems to encapsulate and release urea. Single-layered hollow poly l-lactic acid (PLLA) nanofibre yarns loaded with urea fertiliser were fabricated using a customized electrospinning. Double-layered hollow nanofibre yarns were produced by electrospinning polyhydroxybutyrate (PHB) nanofibres as an outer layer, with urea-impregnated PLLA nanofibres as the inner layer. Scanning electron microscopy (SEM) with an energy-dispersive spectroscopy (EDS) was used to characterize the morphology of hollow electrospun nanofibre yarns. A total nitrogen instrument (TNM-1) was used to study the urea release from single- and double-layered hollow nanofibres yarn in water. A Carbon:Nitrogen (CN) elemental analyser determined encapsulated nitrogen in PLLA nanofibres samples. Results indicated that urea-impregnated double-layered hollow nanofibre yarns significantly started nitrogen releasing at much lower amount during first 12 h compared to single-layered hollow nanofibre yarns (P value = 0.000). In conclusion, double-layered hollow nanofibre yarn has potential as an effective alternative to current methods for the slow release of fertilisers and other plant-required chemicals.


2015 ◽  
Vol 2015 ◽  
pp. 1-11 ◽  
Author(s):  
Chemar J. Huntley ◽  
Kristy D. Crews ◽  
Mohamed A. Abdalla ◽  
Albert E. Russell ◽  
Michael L. Curry

Cellulose extractions from wheat straw via hydrochloric, nitric, and sulfuric acid hydrolysis methods were carried out. X-ray diffraction spectral analyses reveal that depending on the acid conditions used the structure of the cellulose exhibited a mixture of polymorphs (i.e., CI and CIII cellulose phases). In addition, the percent crystallinity, diameter, and length of the cellulose fibers varied tremendously as determined by X-ray diffraction and scanning electron microscopy. Thermal gravimetric analysis measurements revealed that the thermal stability of the extracted cellulose varied as a function of the acid strength and conditions used. Scanning electron microscopy analysis revealed that the aggregation of cellulose fibers during the drying process is strongly dependent upon the drying process and strength of the acids used.


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