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•Coconut fiber and fly ash were hybridized with a silane coupling agent to enhance composite properties.•Silane treatment improved water absorption, tensile strength, and thermal stability.•The treated composite showed a 33 % reduction in water absorption and a 1.8 % increase in tensile strength.•The study provides insights into the effective utilization of organic/inorganic fillers in composites.

This study aims to investigate the kinetics of the amla fruit drying process using oven and sun drying methods. The experimental results indicate that the final moisture content dropped with increasing drying temperature and decreasing material size. Oven drying has a faster drying time than sun drying. The heat loss during oven drying is lower than during sun drying, so the drying rate constant (k) for the oven drying method is higher than for sun drying. Moisture ratios for each drying condition are evaluated using three thin-layer models: Handerson–Pabis, Page, and Newton. The coefficient determination (R2) was used as a statistical parameter to determine the best drying kinetics model. Among the drying models examined, the Page model had the highest accuracy. An increase in drying temperature and a decrease in material size caused the effective moisture diffusivity value (Deff) to increase. The Deffvalues ranged from 4.522×10−10to 1.361×10−9m2/s. Analysis using scanning electron microscopy showed that the microstructure of amla fruit was significantly affected by varied drying conditions.

Synthesis of palm oil-based polyurethane (PU) and the formation of nanocomposite from a mixture of PU with clay filler has been performed. Polyol which is the basic material of PU is formed by epoxidation and hydroxylation process and then mixed with isocyanate. Clay used as filler in this study was obtained from the local area of North Aceh, which is a type of swelling of clay that has been modified with cetyltrimethyl ammonium bromide surfactant. Nanocomposites are formed from PU with clay fill variations of 3%, 5%, and 8% by weight of the total mixture of 40 g. The resulting material is tested in character by some type of characterization. Based on the test results with Fourier transform infrared spectroscopy, the hydroxyl polyol group was obtained in groups of 3390.870 (O–H) and –NH as the PU microdomain structure was obtained at a wavelength of 2987 cm−1. Morphological test results using scanning electron microscopy revealed that the addition of modified clay increases the adhesion in the paint and PU coatings and also increases the gloss from the surface and homogeneous material. The thermal endurance test with thermogravimetric analysis reported that the addition of clay fillers in PU showed enhanced effects for better thermal stability in nanocomposite materials when compared with neat polymers. Samples of PU/clay nanocomposites with the addition of 8 wt% clay filler were the most optimum composites among other variations with the thermal degradation temperature value of 296°C. This research generates prospects for applying various industrial surface coatings that are resistant to corrosion and heat, have good mechanical properties, and are more environmentally friendly.

Ammonia and urea contained in fertilizer plant wastewater are pollutants to the environment. High concentration of ammonium and urea in wastewater can affects algae blooms in the ecosystem which will generate various diseases in aquatic biota. It is known that there are many methods for degradation of ammonium and urea contained in fertilizer plant wastewater. One of the potential method is ultraviolet-enhanced ozonation. Ozonation is oxidation with O3 that generates hydroxyl radicals which subsequently react with organic contaminants, while UV irradiation can break down O3 molecules and produce radical ions OH[?]. The objectives of this study were to examine the effects of the utilization of the ultraviolet-enhanced ozonation method in degradation of various initial ammonium (100-300 ppm) and urea concentration (100-300 ppm) in inlet feed of ozonation-UV irradiation combination system. Some important variables such as contact time (0-120 minutes) and ozone feed rate of 0.2, 0.6, and 1.21 g/h were evaluated. Degradation process was carried out in two steps; ozonation and UV irradiation. Ozonation process was carried out in a contacting tank at a constant feed flow rate of 1.5 l/min and at room temperature, while UV irradiation process was conducted in pipeline equipped with a UV lamp at various contact time. The ultraviolet-enhanced ozonation could degrade ammonium and urea nitrogen up to 83.6% and 63.8%, respectively, at ozone feed rate 1,21 g/h, contacting time 60 and 120 min, initial feed concentration of ammonia (100 ppm) and urea (40 ppm).

Ammonia and urea contained in fertilizer plant wastewater are pollutants to the environment. High concentration of ammonium and urea in wastewater can affects algae blooms in ecosystem which will generate various diseases in aquatic biota. It is known that there are many methods for degradation of ammonium and urea contained in fertilizer plant wastewater. One of potential method is ultraviolet-enhanced ozonation. Ozonation is oxidation with O3 that generates hydroxyl radicals which subsequently react with organic contaminants, while UV irradiation can break down O3 molecules and produce radical ions OH[?]. The objectives of this study were to examine the effects of the utilization of the ultraviolet-enhanced ozonation method in degradation of various initial ammonium (100-300 ppm) and urea concentration (100-300 ppm) in inlet feed of ozonation-UV irradiation combination system. Some important variables such as contact time (0-120 minutes) and ozone feed rate of 0.2, 0.6, and 1.21 g/h were evaluated. Degradation process was carried out in two steps; ozonation and UV irradiation. Ozonation process was carried out in a contacting tank at constant feed flow rate of 1.5 l/min and at room temperature, while UV irradiation process was conducted in pipeline equipped with UV lamp at various contact time. The ultraviolet-enhanced ozonation could degraded ammonium and urea nitrogen up to 83.6% and 63.8%, respectively, at ozone feed rate 1,21 g/h, contacting time 60 and 120 min, initial feed concentration of ammonia (100 ppm) and urea (40 ppm).