Greenhouse experiments were carried out to determine the phytotoxic effects on the plant Ludwigia octovalvis in order to assess its applicability for phytoremediation gasoline-contaminated soils. Using plants to degrade hydrocarbons is a challenging task. In this study, different spiked concentrations of hydrocarbons in soil (1, 2, and 3 g/kg) were tested. The results showed that the mean efficiency of total petroleum hydrocarbon (TPH) removal over a 72-day culture period was rather high. The maximum removal of 79.8 % occurred for the 2 g/kg concentration, while the removal rate by the corresponding unplanted controls was only (48.6 %). The impact of gasoline on plants included visual symptoms of stress, yellowing, growth reduction, and perturbations in the developmental parameters. The dry weight and wet weight of the plant slightly increased upon exposure to gasoline until day 42. Scanning electron microscopy (SEM) indicated change to the root and stem structure in plant tissue due to the direct attachment with gasoline contaminated compared to the control sample. The population of living microorganisms in the contaminated soil was found to be able to adapt to different gasoline concentrations. The results showed that L. octovalvis and rhizobacteria in gasoline-contaminated soil have the potential to degrade organic pollutants.
The synthesis of carbon nanotubes (CNTs) using a chemical vapour deposition (CVD) method requires the use of hydrocarbon as the carbon precursor. Among the commonly used hydrocarbons are methane and acetylene, which are both light gas-phase substances. Besides that, other carbon-rich sources, such as carbon monoxide and coal, have also been reportedly used. Nowadays, researches have also been conducted into utilising heavier hydrocarbons and petrochemical products for the production of CNTs, such as kerosene and diesel oil. Therefore, this article reviews the different kind of hydrocarbon sources for CNTs production using a CVD method. The method is used for it allows the decomposition of the carbon-rich source with the aid of a catalyst at a temperature in the range 600-1200°C. This synthesis technique gives an advantage as a high yield and high-quality CNTs can be produced at a relatively low cost process. As compared to other processes for CNTs production such as arc discharge and laser ablation, they may produce high quality CNTs but has a disadvantage for use as large scale synthesis routes.
In this research, the biodiesel from WCO is used in order to reduce the exhaust emission and to investigate the
community perception regarding to the human health. Biodiesel production is conducted using trans-esterification
process with holding time of 2 hours, temperature of 60 oC and conventional frequency of 20 kHz and then followed
by washing process with holding time of 1 hours, temperature of 50 oC and the frequency of 5 kHz. Biodiesel can
reduce exhaust emission of NOx up to 55%, NO gas up to 57%, increase CO gas up to 25% and increase CO2 gas up
to 43.18% as compared to diesel fuel. In addition, biodiesel is achieve good responds from 35 respondents about the
biodiesel importance.
A study has been conducted on trans,trans-muconic acid (t,t-MA) as the biomarker for benzene exposure among
oil and gas petrol tanker drivers. The objectives of this study are to determine the significant difference and the
correlation between Benzene personal exposure and urinary t,t-MA among exposed and non-exposed workers. A total
of 92 questionnaires were distributed to obtain demographic and descriptive data. Benzene personal exposure was
sampled using SKC passive samplers and the data was analyzed using GC-FID. Urinary t,t-MA was collected at end of
work shift and analyzed using HPLC-UV detector. A total of 30 non-exposed workers were also sampled. The averages
of urinary t,t-MA were 96.65 ug/g creatinine for exposed workers and 0.51 ug/g creatinine for non-exposed workers.
Meanwhile, the averages of Benzene personal exposure were 0.37 mg/m3 and 0.01 mg/m3 for exposed workers and
non-exposed workers respectively. No significant correlation was found between exposure to benzene with excreted
urinary t,t-MA of workers occupationally exposed (p-value > 0.05) as well as to workers non-exposed to benzene
(p-value > 0.05). In conclusion, there is no significant correlation found between Benzene personal exposure and
urinary t,t-MA among exposed and non-exposed workers. Applicability of using t,t-MA as the biomarker of benzene
exposure shall be further discussed with all the other confounding factors to be taken into account.
This study was set up to model and optimize the performance and emission characteristics of a diesel engine fueled with carbon nanoparticle-dosed water/diesel emulsion fuel using a combination of soft computing techniques. Adaptive neuro-fuzzy inference system tuned by particle swarm algorithm was used for modeling the performance and emission parameters of the engine, while optimization of the engine operating parameters and the fuel composition was conducted via multiple-objective particle swarm algorithm. The model input variables were: injection timing (35-41° CA BTDC), engine load (0-100%), nanoparticle dosage (0-150 μM), and water content (0-3 wt%). The model output variables included: brake specific fuel consumption, brake thermal efficiency, as well as carbon monoxide, carbon dioxide, nitrogen oxides, and unburned hydrocarbons emission concentrations. The training and testing of the modeling system were performed on the basis of 60 data patterns obtained from the experimental trials. The effects of input variables on the performance and emission characteristics of the engine were thoroughly analyzed and comprehensively discussed as well. According to the experimental results, injection timing and engine load could significantly affect all the investigated performance and emission parameters. Water and nanoparticle addition to diesel could markedly affect some performance and emission parameters. The modeling system could predict the output parameters with an R2 > 0.93, MSE
Present data article based on the investigation which enumerates the influence of CNG (compressed natural gas) and HCNG (hydrogen enriched compressed natural gas) on performance and emission parameters of direct injection diesel engine at 200, 220, and 240 bar injection pressures. The CNG and HCNG gaseous alternative fuels were injected in amount (by mass) of 10%, 20% and 30% as secondary fuels to enrich the pilot fuel (pure diesel) during the operation. The performance and emission data of dual fuel (CNG + pure diesel, HCNG + pure diesel) operation was analysed to compare with the pure diesel data. The data for present investigational work were assessed at 25%, 50%, 75% and 100% diverse engine loads for all trials under diverse injection pressures. Eddy current dynamometer was employed to raise the engine load from quartile to maximum. AVL DiGAS 444 N multi gas analyser was used to measure the values of carbon monoxide (CO), unburned hydrocarbon (UHC), and oxides of nitrogen (NOx) detrimental emissions in engine exhaust.
Compound-specific isotope analysis offers potential for fingerprinting of diesel fuels, however, possible confounding effects of isotopic fractionation due to evaporation need to be assessed. This study measured the fractionation of the stable carbon and hydrogen isotopes in n-alkane compounds in neat diesel fuel during evaporation. Isotope ratios were measured using a continuous flow gas chromatograph/isotope ratio mass spectrometer. Diesel samples were progressively evaporated at 24 ± 2°C for 21 days. Increasing depletion of deuterium in nC12-nC17 alkanes in the remaining liquid with increasing carbon chain length was observed. Negligible carbon isotope fractionation was observed. Preferential vaporization was measured for the shorter chain n-alkanes and the trend decreased with increasing chain length. The decrease in δ(2) H values indicates the preferential vaporization of the isotopically heavier species consistent with available quantitative data for hydrocarbons. These results are most important in the application of stable isotope technology to forensic analysis of diesel.
Petrol is known to be hazardous to human health and is associated with various health effects, such as haematotoxicity and oxidative stress. Although Malaysia has adopted the European fuel quality standards in recent years in order to reduce petroleum pollutants and to improve air quality, gasoline with research octane number 95 (RON95), believed to contain benzene and other toxic substances, is still widely used all over the country. This study assessed the effect of RON95 gasoline on haemtological parameters of rats after 11 weeks of exposure.
Compound-specific isotope analysis (CSIA) offers great potential as a tool to provide chemical evidence in a forensic investigation. Many attempts to trace environmental oil spills were successful where isotopic values were particularly distinct. However, difficulties arise when a large data set is analyzed and the isotopic differences between samples are subtle. In the present study, discrimination of diesel oils involved in a diesel theft case was carried out to infer the relatedness of the samples to potential source samples. This discriminatory analysis used a suite of hydrocarbon diagnostic indices, alkanes, to generate carbon and hydrogen isotopic data of the compositions of the compounds which were then processed using multivariate statistical analyses to infer the relatedness of the data set. The results from this analysis were put into context by comparing the data with the δ(13)C and δ(2)H of alkanes in commercial diesel samples obtained from various locations in the South Island of New Zealand. Based on the isotopic character of the alkanes, it is suggested that diesel fuels involved in the diesel theft case were distinguishable. This manuscript shows that CSIA when used in tandem with multivariate statistical analysis provide a defensible means to differentiate and source-apportion qualitatively similar oils at the molecular level. This approach was able to overcome confounding challenges posed by the near single-point source of origin, i.e., the very subtle differences in isotopic values between the samples.
The data consists of actual generation-side auditing including the distribution of loads, seasonal load profiles, and types of loads as well as an analysis of local development planning of a resort island in the South China Sea. The data has been used to propose an optimal combination of hybrid renewable energy systems that able to mitigate the diesel fuel dependency on the island. The resort island selected is Tioman, as it represents the typical energy requirements of many resort islands in the South China Sea. The data presented are related to the research article "Optimal Combination of Solar, Wind, Micro-Hydro and Diesel Systems based on Actual Seasonal Load Profiles for a Resort Island in the South China Sea" [1].
The aim of this study is to investigate the effect of the polymethyl acrylate (PMA) additive on the formation of particulate matter (PM) and nitrogen oxide (NOX) emission from a diesel coconut and/or Calophyllum inophyllum biodiesel-fueled engine. The physicochemical properties of 20% of coconut and/or C. inophyllum biodiesel-diesel blend (B20), 0.03 wt% of PMA with B20 (B20P), and diesel fuel were measured and compared to ASTM D6751, D7467, and EN 14214 standard. The test results showed that the addition of PMA additive with B20 significantly improves the cold-flow properties such as pour point (PP), cloud point (CP), and cold filter plugging point (CFPP). The addition of PMA additives reduced the engine's brake-specific energy consumption of all tested fuels. Engine emission results showed that the additive-added fuel reduce PM concentration than B20 and diesel, whereas the PM size and NOX emission both increased than B20 fuel and baseline diesel fuel. Also, the effect of adding PMA into B20 reduced Carbon (C), Aluminum (Al), Potassium (K), and volatile materials in the soot, whereas it increased Oxygen (O), Fluorine (F), Zinc (Zn), Barium (Ba), Chlorine (Cl), Sodium (Na), and fixed carbon. The scanning electron microscope (SEM) results for B20P showed the lower agglomeration than B20 and diesel fuel. Therefore, B20P fuel can be used as an alternative to diesel fuel in diesel engines to lower the harmful emissions without compromising the fuel quality.
Diesel is commonly used as fuel for engines and is distilled from petroleum. Diesel has toxic potential and can affect multiple organs. Exposure can occur after ingestion, inhalation or through the dermal route. The practice of siphoning diesel using a rubber tubing and the mouth is common in rural communities. This can lead to accidental ingestion and aspiration. Here we report a case of a patient who accidentally ingested diesel during siphoning, which caused extensive erosion of the oral cavity and oesophagus leading to pneumomediastinum and severe chemical lung injury. The patient responded well initially to steroids and supportive care but required prolonged hospitalisation. He developed complications of nosocomial infection and succumbed 23 days after admission.
The focus of this work is to investigate the emission characteristics of a stationary diesel engine while utilizing an emulsion fuel from a novel preparation process. The emulsion preparation was performed in real time without using any surfactant. Instead of mechanically breaking the water down into droplets, the water is delivered thermally, by changing its phase from gas to liquid. Steam is used in this proposed process, where it will be converted into suspended water droplets once it meets colder diesel. The product is called steam-generated water-in-diesel emulsion fuel (S/D). The method is expected to reduce the moving components of a previous surfactant-less system; therefore, reducing costs and increasing the system reliability. The emission characteristics of S/D were compared with EURO 2 diesel (D2), and a conventional emulsion denoted as E10. E10 was prepared using 10% water (volumetric) and SPAN80 as a surfactant. The emission characterizations were carried out based on the exhaust gas of a single cylinder naturally aspirated CI engine fueled with D2, S/D, and E10. Compared to D2, both emulsions significantly reduced the emissions of nitrogen oxides (NOx) (E10 max ↓58.0%, S/D max ↓40.0%) and particulate matter (PM) (E10 max ↓20.0%, S/D max ↓57.0%).
Non-surfactant water-in-diesel emulsion fuel (NWD) is an alternative fuel that has the potential to reduce major exhaust emissions while simultaneously improving the combustion performance of a diesel engine. NWD comprises of diesel fuel and water (about 5% in volume) without any additional surfactants. This emulsion fuel is produced through an in-line mixing system that is installed very close to the diesel engine. This study focuses mainly on the performance and emission of diesel engine fuelled with NWD made from different water sources. The engine used in this study is a direct injection diesel engine with loads varying from 1 to 4 kW. The result shows that NWD made from tap water helps the engine to reduce nitrogen oxide (NOx) by 32%. Rainwater reduced it by 29% and seawater by 19%. In addition, all NWDs show significant improvements in engine performance as compared to diesel fuel, especially in the specific fuel consumption that indicates an average reduction of 6%. It is observed that all NWDs show compelling positive effects on engine performance, which is caused by the optimum water droplet size inside NWD.
Employment of edible oils as alternative green fuel for vehicles had raised debates on the sustainability of food supply especially in the third-world countries. The non-edible oil obtained from the abundantly available rubber seeds could mitigate this issue and at the same time reduce the environmental impact. Therefore, this paper investigates the catalytic cracking reaction of a model compound named linoleic acid that is enormously present in the rubber seed oil. Batch-scale experiments were conducted using 8.8 mL Inconel batch reactor having a cyclic horizontal swing span of 2 cm with a frequency of 60 cycles per minute at 450 °C under atmospheric condition for 90 min. The performance of HZSM-5, HBeta, HFerrierite, HMordenite and HY catalysts was tested for their efficiency in favouring gasoline range hydrocarbons. The compounds present in the organic liquid product were then analysed using GC-MS and classified based on PIONA which stands for paraffin, isoparaffin, olefin, naphthenes and aromatics respectively. The results obtained show that HZSM-5 catalyst favoured gasoline range hydrocarbons that were rich in aromatics compounds and promoted the production of desired isoparaffin. It also gave a higher cracking activity; however, large gaseous as by-products were produced at the same time.
The present work analyzes the effect of antioxidants on engine combustion performance of a multi-cylinder diesel engine fueled with PB30 and PB50 (30 and 50 vol.% palm biodiesel (PB)). Four antioxidants namely N,N'-diphenyl-1,4-phenylenediamine (DPPD), N-phenyl-1,4-phenylenediamine (NPPD), 2(3)-tert-Butyl-4-methoxyphenol (BHA), and 2-tert-butylbenzene-1,4-diol (TBHQ) were added at concentrations of 1000 and 2000 ppm to PB30 and PB50. TBHQ showed the highest activity in increasing oxidation stability in both PB30 and PB50 followed by BHA, DPPD, and NPPD respectively, without any negative effect on physical properties. Compared to diesel fuel, PB blends showed 4.61-6.45% lower brake power (BP), 5.90-8.69% higher brake specific fuel consumption (BSFC), 9.64-11.43% higher maximum in cylinder pressure, and 7.76-12.51% higher NO emissions. Carbon monoxide (CO), hydrocarbon (HC), and smoke opacity were reduced by 36.78-43.56%, 44.12-58.21%, and 42.59-63.94%, respectively, than diesel fuel. The start of combustion angles (SOC) of PB blends was - 13.2 to - 15.6 °CA BTDC, but the combustion delays were 5.4-7.8 °CA short compared to diesel fuel which were - 10 °CA BTDC and 11°CA respectively. Antioxidant fuels of PB showed higher BP (1.81-5.32%), CO (8.41-24.60%), and HC (13.51-37.35%) with lower BSFC (1.67-7.68%), NO (4.32-11.53%), maximum in cylinder pressure (2.33-4.91%) and peak heat release rates (HRR) (3.25-11.41%) than baseline fuel of PB. Similar SOC of - 13 to - 14 °CA BTDC was observed for PB blended fuels and antioxidants. It can be concluded that antioxidants' addition is effective in increasing the oxidation stability and in controlling the NOx emissions of palm biodiesel fuelled diesel engine.
Mycobacterium cosmeticum is a nontuberculous Mycobacterium recovered from different water sources including household potable water and water collected at nail salon. Individual cases of this bacterium have been reported to be associated with gastrointestinal tract infections. Here we present the first whole-genome study and comparative analysis of two new clinically-derived Mycobacterium sp. UM_RHS (referred as UM_RHS after this) and Mycobacterium sp. UM_NYF (referred as UM_NYF after this) isolated from patients in Indonesia and Malaysia respectively to have a better understanding of the biological characteristic of these isolates. Both strains are likely Mycobacterium cosmeticum as supported by the evidence from molecular phylogenetic, comparative genomic and Average Nucleotide Identity (ANI) analyses. We found the presence of a considerably large number of putative virulence genes in the genomes of UM_RHS and UM_NYF. Interestingly, we also found a horizontally transferred genomic island carrying a putative dsz operon proposing that they may have potential to perform biodesulfization of dibenzothiophene (DBT) that may be effective in cost reduction and air pollution during fuel combustion. This comparative study may provide new insights into M. cosmeticum and serve as an important reference for future functional studies of this bacterial species.
The problems of global warming and the unstable price of petroleum oils have led to a race to develop environmentally friendly biofuels, such as palm oil or ethanol derived from corn and sugar cane. Biofuels are a potential replacement for fossil fuel, since they are renewable and environmentally friendly. This paper evaluates the combustion performance and emission characteristics of Refined, Bleached, and Deodorized Palm Oil (RBDPO)/diesel blends B5, B10, B15, B20, and B25 by volume, using an industrial oil burner with and without secondary air. Wall temperature profiles along the combustion chamber axis were measured using a series of thermocouples fitted axially on the combustion chamber wall, and emissions released were measured using a gas analyzer. The results show that RBDPO blend B25 produced the maximum emission reduction of 56.9% of CO, 74.7% of NOx, 68.5% of SO(2), and 77.5% of UHC compared to petroleum diesel, while air staging (secondary air) in most cases reduces the emissions further. However, increasing concentrations of RBDPO in the blends also reduced the energy released from the combustion. The maximum wall temperature reduction was 62.7% for B25 at the exit of the combustion chamber.
A diesel-degrading bacterium was isolated from a diesel-contaminated site in Selangor, Malaysia. The isolate was tentatively identified as Acinetobacter sp. strain DRY12 based on partial 16S rDNA molecular phylogeny and Biolog GN microplate panels and Microlog database. Optimum growth occurred from 3 to 5% diesel and the strain was able to tolerate as high as 8% diesel. The optimal pH that supported growth of the bacterium was between pH 7.5 to 8.0. The isolate exhibited optimal growth in between 30 and 35 degrees C. The best nitrogen source was potassium nitrate (between 0.6 and 0.9% (w/v)) followed by ammonium chloride, sodium nitrite and ammonium sulphate in descending order. An almost complete removal of diesel components was seen from the reduction in hydrocarbon peaks observed using Solid Phase Microextraction Gas Chromatography analysis after 10 days of incubation. The best growth kinetic model to fit experimental data was the Haldane model of substrate inhibiting growth with a correlation coefficient value of 0.97. The maximum growth rate- micromax was 0.039 hr(-1) while the saturation constant or half velocity constant Ks and inhibition constant Ki, were 0.387% and 4.46%, respectively. MATH assays showed that 75% of the bacterium was found in the hexadecane phase indicating that the bacterium was hydrophobic. The characteristics of this bacterium make it useful for bioremediation works in the Tropics.
In this study, bulrush (Scirpus grossus) was subjected to a 72 day phytotoxicity test to assess its ability to phytoremediate diesel contamination in simulated wastewater at different concentrations (0, 8700, 17,400 and 26,100mg/L). Diesel degradation by S. grossus was measured in terms of total petroleum hydrocarbon (TPH-D). The TPH-D concentration in the synthetic wastewater was determined with the liquid-liquid extraction method and gas chromatography. S. grossus was found to reduce TPH-D by 70.0 and 80.2% for concentrations of 8700 mg/L and 17,400mg/L, respectively. At a diesel concentration of 26,100mg/L, S. grossus died after 14 days. Additionally, the biomass of S. grossus plants was found to increase throughout the phytotoxicity test, confirming the ability of the plant to survive in water contaminated with diesel at rates of less than 17,400mg/L.