Sulfur and nitrogen removal of model fuel using activated carbon derived from oil palm shell

This research was done to understand the suitability and effectiveness of oil palm shells (OPS) as low cost adsorbents via physically activation with carbon dioxide (CO2) as an adsorbent for desulphurization and denitrogenation of a model fuel under different concentration. Batch mode experiments were conducted to study the effects concentration of Benzothiophine, Quinoline and Indole. Activated carbon (AC) was prepared at three different activation temperatures (500°C, 600°C, and 700°C), which was characterized with Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (mR), and a mercury intrusion porosimeter. After adsorption, the solution was analysed with a Gas Chromatography (GC). Equilibrium adsorption isotherms and kinetics were investigated. The experimental data were analysed by the Langmuir and Freundlich models of adsorption. The adsorption isotherm data were fitted well to Langmuir isotherm and the most adsorption capacity on the best suited AC for Benzothiophene, Quinoline, and Indole were 3.64 mg/g, 4.19 mg/g and 2.98 mg/g respectively. The rates of adsorption were 0.19409 h-1, 0.08411 h-1, and 0.02883 h-1 for the adsorption of Benzothiophene, Quinoline, and Indole respectively. The kinetic data obtained at different concentrations have been analysed using a pseudo-first-order, pseudo-second-order equation and intraparticle diffusion equation. The pseudo-first­order model best described the sorption process and was employed in predicting the rate constant, equilibrium sorption capacity as well

Genetic variation of selected Camellia sinensis (Cultivated Tea) varieties in Malaysia based on random amplified microsatellite (RAMs) markers

Studies on the genetic variation among Camellia sinensis L. varieties (cultivated tea) in Malaysia were conducted by using RAMs markers. Six varieties were selected from Sungai Palas Boh Estate, Cameron Highlands and nine varieties were selected from Bukit Cheeding Boh Estate, Banting. These tea varieties were classified as resistant, intermediate, or susceptible varieties based on the level of infestation by the mosquito bug, Helopeltis theivora. DNA was extracted from the leaves of 225 individuals belonging to different varieties from the two populations. Four RAMs primers were used to evaluate the genetic variation in 15 varieties of tea. Distances were calculated based on Nei and Li’s (1979) similarity coefficients using the data from the RAMs markers. A cluster analysis employing UPGMA was done and the dendrogram grouped the tea varieties into two clusters with intermediate variety grouping and the resistant (the first cluster) or susceptible (the second cluster) varieties. The first cluster consisted of all the varieties from Cameron Highlands, except for BC223 (resistant) and 63/14 (resistant) from the Banting population, while the other clusters consisted of all the varieties from the Banting population, except for BC196 (resistant) from the Cameron Highlands population. The dendrogram showed that the genetic differences were based on the populations’ geographical distributions and partially based on their resistance towards attack by H. theivora

Carbon dioxide removal by adsorption

Carbon dioxide (CO2) among other air pollutants is a major culprit to the greenhouse gases that is fueling global warming. To mitigate global warming, Kyoto Protocal urges 37 industrialized nations and European Union to reduce their greenhouse gas emissions to a level of 5.2% on average lower than those of 1990 during the period of 2008-2012. It is therefore essential to develop the CCS technologies to cope with the global demand of CO2 reduction. In this study the technologies of CO2 removal are reviewed

Sonolysis, photolysis, and sequential sonophotolysis for the degradation of 2,4,6-Trichlorophenol: the effect of solution concentration

Ultrasonic sound waves, ultraviolet-A irradiation and a combination of these two techniques were applied to a non-catalytic aqueous system containing 2,4,6-trichlorophenol (TCP) to study the effectiveness of sonolytic, photolytic and sonophotolytic oxidation processes in the degradation of TCP. The operating parameters for the horn-type sonicator and the UV-A lamp were kept constant along with the solution temperature but the TCP concentration was varied from 30 to 90 ppm. A first-order kinetic rate model was used to study the synergistic effect of the sonophotodegradation process. It was found that at a lower TCP concentration of 30 ppm, sonophotodegradation exhibited a synergistic effect but at a TCP concentration of 70 ppm and higher, sonophotodegradation resulted in an antagonistic effect. The synergistic effect was explained in terms of an increase in the ·OH radical formation by the combined process complemented by the photolysis of H2O2 formed by sonolysis. In contrast, the antagonistic effect was explained in terms of the combined effect of viscosity increase resulting in the reduction of the cavitation efficiency and degradation rate, and by considering the dynamics of bubble growth and implosion

Influence of uncertainty in dielectric properties on the design performance of a tunable composite right/left handed leaky wave antenna

Uncertainties of the order of 8 % in the accuracy of lithography used to define co-planar waveguides on ferroelectric thin films lead to a similar uncertainty in the value of relative permittivity of the film extracted from measurements. When such films are used as the tunable elements in a tunable composite right/left handed leaky wave antenna, such variations of the capacitance of the varactors can lead to a reduction in radiation and total efficiency around of the order of 1 dB in 5 dB due to the appearance of a bandgap in the frequency response

Removal of Chlorinated Phenol from Aqueous Media by guava seed (Psidium Guajava) Tailored Activated Carbon

In this study, the activated carbons (ACs) were prepared from guava seeds via two stages activation. The dried guava seeds were semi-carbonized at 300 °C for 1 h, and then the carbonized samples were impregnated with zinc chloride (ZnCl2). The ZnCl2: sample impregnation ratios (w/w) were altered from 1:1 to 5:1. The ACs were characterized by the yield percentage, ash content, moisture content, pH value, adsorption quality of 2,4-dichlorophenol (2,4-DCP) and surface functional groups. The surface area of the best produced AC3 was found to be 919.40 m2 g-1. It was found that AC3 had highest 2,4-DCP adsorption capacity, which was 20.9 mg g-1. The 2,4-DCP adsorption kinetic of prepared AC3 was pseudo-second order with correlation value of 0.995. In addition, the 2,4-DCP adsorption capacity of AC3 was fitted to the Langmuir model with correlation coefficient value of 0.977, indicating that chemisorption was a major contributor to the adsorption process

Sorption studies of Methylene Blue in aqueous solution by optimized carbon prepared from Guava seeds (Psidium guajaval)

The aim of this investigation was to determine the adsorption behavior and kinetics of methylene blue in aqueous solution on activated carbons prepared from guava seeds by way of the two stage activation method in self-generated atmosphere using a muffle furnace. The yield and ash contents of the activated carbons obtained decreased with the increase of activation temperature and time. FT-IR spectra indicated high surface functional groups present in the carbons. The optimised activated carbon, AK6, had a sorption kinetics that complied with the pseudo-second order kinetics and was fitted well to Langmuir isotherm model. The highest adsorption capacity was obtained when the samples (AK6) were subjected to activation temperature of 500 °C for 45 minutes giving iodine number of 198.12 mg g–1 and the percentage of methylene blue removal efficiency of 84.75 %

Preparation of titanium dioxide photocatalyst loaded onto activated carbon support using chemical vapor deposition: a review paper

Various methods to prepare and characterize TiO2 photocatalyst loaded onto activated carbon (AC) support have been developed over the last decade. This photocatalyst has been used in a variety of investigations, i.e. from water decontamination to direct pollutant degradation in aqueous and gas phase systems using UV irradiation and lately with the assistance of ultrasonic sound waves. Chemical vapor deposition (CVD) method is one of the most promising and well-researched methods for deposition of catalysts onto supports. Given its advantage, from an engineering and fundamental aspect, CVD method also has commercial applications. A detailed search of published reports of these investigations was carried out and analyzed in this paper with focus on CVD techniques, activated carbon support and sonication

In vitro assay of factors affecting the growth of pathogens associated with diseases on dragon fruits (Hylocereus spp.) in Peninsular Malaysia.

Knowing the unfavorable environment for the growth of a pathogen can be utilized as the basic information in developing appropriate strategies to prevent disease occurrence on dragon fruit. Several environmental factors including temperature, pH and salinity, as well as biotic factor including three antagonistic bacteria species, namely Bukholderia cepacia, B. multivorans and Pseudomonas aeruginosa against Bipolaris sp., Colletotrichum gloeosporioides, Botryosphaeria sp. and Monilinia sp., were investigated. Mycelial growth of all tested fungi was constantly inhibited by a temperature of 35°C, while a temperature of 25°C was quite suitable for their growth. A temperature of 30°C was favorable for the growth of Colletotrichum gloeosporioides. Under different pH condition, the growth of tested fungi was mostly inhibited by extreme pH of 4 and 10. The salinity assay showed that Monilinia sp. was not affected by all treatments among tested fungi. Only concentration 100 ppm could reduce the growth of Bipolaris sp., though its inhibition statistically affected on 4 and 6 Days after Incubation (DAI). Meanwhile, the in vitro examination of antagonistic bacteria resulted in Bukholderia multivorans which was highly effective in inhibiting the growth of examined fungi, except Monilinia sp., which was more significantly influenced by B. multivorans and B. cepacia. The proper combination of environmental modification may be useful for the growth of crop in the field as well as the storage life of the fruit at postharvest preservation

Distribution of two Pomacea spp. in rice fields of Peninsular Malaysia

Aim:This study aims to understand the distribution of Pomaceaspp. in various rice fields of Peninsular Malaysia. Place and Duration of study:The study was conducted at twenty five rice fieldsfrom five states in Peninsular Malaysia (Selangor, Perak, Penang, Kedah and Kelantan) during the sowing and harvesting of off rice season-2013. Methodology:This study was carried out on rice fields of one acre in size which were further divided into four blocks. A 0.5m2 quadrate was used for sampling and snails within the quad rate were collected, counted and identified based on their shell morphology by the experts. Results:Based on this study, Pomacea maculata was more abundant and widely distributed as compared to Pomacea canaliculata. Rice fields in Perak showed the highest population distribution of Pomacea spp. during both sowing and harvesting of rice. Meanwhile, the lowest population was observed in rice fields during the sowing of rice in Kelantan and during harvesting of rice in Kedah. Comparatively higher population of Pomacea spp. was recorded during sowing of rice than harvesting. No population of P. canaliculata was observed from the rice fields of Penang state. Water temperature, p Hand the number of rice seedlings does not have a significant effect on the distribution of Pomacea spp. Conclusion:The results from this study could help in an area wide management program against Pomaceaspp., not only to minimize their damage to rice but also to control their further spread