Papers by Keyword: Organic Pollutants

Abstract: Some organic pollutants change the color, smell, and other characteristics of water leaving it undesirable for use. However, other organic pollutants do not change the physical properties of the water, yet, they make the water non-useful. This study was carried out to determine the characteristics of petroleum contaminated water and how it can be purified using economical filters for possible reuse in rural areas of the Niger Delta, of Nigeria. The filters were made from rice husk ash, and white clay, as main materials, while calcium carbonate and poly (propylene carbonate) were used as binders and pore former. The water samples were tested for conductivity, turbidity, pH, heavy metals, and total hydrocarbon contents. The results showed a significant decrease in the amount of petroleum/organic pollutants present in the water sample before purification. The filter candle made using poly (propylene carbonate) as a binder was found to be the most efficient in removing organic pollutants, but it was not very effective in the removal of heavy metals and also, the pH of the filtrate became more acidic. Filtrates from other filters, however, had pH in an acceptable range. Dodecanoic acid and hexadecanoic acid were found to be removed from the polluted water using the filters.

Abstract: Greywater is a wastewater originating from shower, bathtub, bathroom sink, kitchen sink and laundry. Despite the fact of wastewater in Malaysia may also include a complex mixture of organic matter, suspended solids, bacteria and common household chemicals, when used wisely and in a manner that is protective to public health and the environment, it can helps preserve limited water supply. This study aims the efficiency of adsorption of organic pollutants in greywater by using natural fibers such as Kenaf dust and Chitosan powder to treat the colour of water and the cause of odours from the greywater. The objective of this research is to identify the characteristics of greywater according to standard effluent discharge, as well as to characterize the physical properties of Kenaf (Hibiscus Cannabinus L.) and to determine the percent removal parameters of greywater by using Kenaf dust and Chitosan powder as organic removal. Raw greywater samples were taken at main drain Kompleks Parit Raja. The results for raw greywater samples obtained such as COD (253 mg/l), TSS (1800 mg/l), pH (5.89) and turbidity (47.5 NTU) were compared to Effluent Standard Discharge (EQA 1974). The COD removal efficiencies by using kenaf dust and chitosan powder amounted to 51% and 50 %, also TSS removal 89% and 100%. The pH and turbidity amounted to 6.76 and 7.04, 46 NTU and 4.46 NTU respectively. The overall removal of organic pollutants increased with different mass of adsorbents, then the optimum adsorbents were selected 30%, 40% and 50% to form as beads.

Abstract: Abstract. The large-pore mesoporous Bi-B-TiO2 nanoparticles with the different Bi/Ti rations were prepared by EISA(evaporation-induced self-assembly) method. The prepared catalysts were characterized by X-ray diffraction, transmission electron microscopy, N2 absorption-desorption, ultraviolet visible light spectroscopy and photoluminescence spectroscopy technologies. The results revealed that all the samples are large aperture mesoporous structures. The crystallite sizes were in the range7-11nm, as confirmed by the results obtained from TEM images. The photodecomposition experiments showed that the photodegradation activity of Bi-B-doped TiO2 was higher than that of undoped TiO2 in degradation of 2, 4–dichlorophenol under visible light irradiation.

Abstract: In this study, three kinds of catalysts for ozone catalytic were fabricated and their effects on organic removal were investigated, moreover the influencing factors in manufacturing were investigated by orthogonal experiments. The prepared Cu/Al₂O₃, Mn/Al₂O₃ and Fe/ Al₂O₃ improved UV₂₅₄ removal of ozone by 12%, 3% and-2%, when ozone was combined with activated carbon filtration, the removal of UV₂₅₄ was improved by 16%, 14% and 8% respectively. Cu/Al₂O₃ was chosen as a model catalyst and its effluencing factors in preparation, including impregnation concentration, impregnation time and calcinations temperature, were analyzed in orthogonal experiments. The orthogonal experiments showed that impregnation time has the biggest effluence in catalytic effect, which followed by calcinations temperature and impregnation concentration.

Abstract: Environment pollution may cause many negative impacts on human health. Among these impacts, human pay more and more attention to adverse pregnancy. This paper reviewed adverse pregnancy outcomes caused by environmental pollutants. The result showed that gaseous pollutants can cause preterm birth and intrauterine growth retardation. Organic pollutants may affect birth weight and neural tube development etc. Heavy metals of cadmium and lead not only affect birth weight, birth length, but also cause congenital malformations. The impact of particulate matter on pregnancy was rarely reported. Further research on the relationship between environmental pollutants and pregnancy will benefit our understanding on and prevention of adverse pregnancy.

Abstract: In this work, we reported the photocatalytic activities of carbon nitride (CN) materials for removal of various aromatic organic pollutants under visible light irradiation. Both bulk carbon nitride (BCN) and mesoporous carbon nitride (MCN) were prepared similarly through thermal polymerization of urea precursor, except that the mesoporous structure was generated onto the MCN via hard template approach using silica nanoparticles. Successful preparations of both BCN and MCN were suggested from various characterization techniques using XRD, DR UV-Visible spectroscopy, nitrogen adsorption-desorption analyzer, and TEM. The prepared BCN and MCN were tested for removal of aromatic organic pollutants, which were benzene, phenol and salicylic acid under visible light irradiation. Both BCN and MCN did not exhibit any photocatalytic activities in the removal of benzene, but active for removals of phenol and salicylic acid. The structure stability and the presence of electron donating group on the organic pollutants were proposed to affect the photocatalytic removal reactions. Owing to the larger BET specific surface area, MCN showed much higher photocatalytic activity than the BCN for removal of phenol and salicylic acid.

Abstract: Graphene-based composites show much better adsorption capacity and other properties than single graphene under the same operating conditions. This paper summarized the different kinds of graphene-based composites removing various heavy metals and organic pollutants in wastewater.

Abstract: In this paper, two newly explored TiO₂ photocatalyst sensitized with commercial stable pigment (BYH3G and PR254) were prepared and characterized by FT–IR, UV–Vis, XRD and N₂ adsorption-desorption isotherms. The adsorption capacities and the photocatalytic activities of as-prepared photocatalysts were evaluated by photocatalytic degradation of Methyl Orange and Rhodamine B under visible light irradiation. The as-prepared photocatalysts displayed high visible light photocatalytic activity than pure TiO₂ under the same conditions. The photocatalytic activity can be reproduced commendably demonstrates that the as-prepared photocatalysts are stable and renewable, which are potentially important properties in the application of industrial wastewater treatment.

Abstract: The application of microwave catalysis technology in environment pollution abatement has developed fast in recent years. This paper will primarily introduce the fundamental of microwave catalysis reaction, microwave induced reduction of SO2 and NOx and acid gas pollutants abatement, microwave induced oxidation and organic pollutants removal, microwave induced catalytic reduction and photosynthesis simulation and other technological methods closely related with environment pollution abatement.

Abstract: We sampled total of 74 polluted soil samples in the polluted field by means of setting 37 plane sample points and digged sampling caves according to the original producing layout and pollution situation of Suzhou chemical plant. The total quantity and the concentration of active form of heavy metal elements in the soil samples were analyzed by atomic absorption spectra; and the volatility organics in the soil are measured using jointed gas chromatography-mass spectrograph measurement. The results show that the polluted area is over 30%. The main pollutants are carbon tetrachloride, methylene chloride, aromatic compounds in the north part of the field, and toluene, P-dichlorobenzene, and petroleum hydrocarbons in the south part. The main pollutants underground 2-3 m are petroleum-derived hydrocarbons, volatile halogenated hydrocarbons, and aromatic compounds.