In an attempt to mitigate the effects of extreme natural events caused by greenhouse gases (GHGs), a significant number of researchers and environmentalists have repeatedly stressed the importance of implementing protective measures, including the promotion of green consumption. This study examined the elements that motivated the willingness and the practice of green behavior (GB) among low-income households in coastal Peninsular Malaysia. To meet the research objectives, this study adopted the survey questionnaire method to collect data from 380 low-income households. The findings revealed that self-efficacy (SE) and environmental concerns (EC) have statistically significant effects on the attitude toward green products (ATT), while subjective norms (SN) and perceived behavioral control (PBC) have influence on the intention of green vehicles. Eventually, the study discovered the effects of the intention to adopt green vehicle on green vehicle adoption behavior. Hence, the findings of this study provide new insights for policymakers in Malaysia to place more emphasis on improving consumer attitudes, social standards, and PBC, which will ultimately contribute to the adoption of environment-friendly vehicles. In addition, car manufacturers should support this program by designing products and options that would encourage those in the low-income group to replace their conventional vehicles with green alternatives in Malaysia.
Exploring new renewable energy sources as a substitute of petroleum reserves is necessary due to fulfilling the oncoming energy needs for industry and transportation systems. In this quest, a lot of research is going on to expose different kinds of new biodiesel sources. The non-edible oil from candlenut possesses the potential as a feedstock for biodiesel production. The present study aims to produce biodiesel from crude candlenut oil by using two-step transesterification process, and 10%, 20%, and 30% of biodiesel were mixed with diesel fuel as test blends for engine testing. Fourier transform infrared (FTIR) and gas chromatography (GC) were performed and analyzed to characterize the biodiesel. Also, the fuel properties of biodiesel and its blends were measured and compared with the specified standards. The thermal stability of the fuel blends was measured by thermogravimetric analysis (TGA) and differential scan calorimetry (DSC) analysis. Engine characteristics were measured in a Yanmar TF120M single cylinder direct injection (DI) diesel engine. Biodiesel produced from candlenut oil contained 15% free fatty acid (FFA), and two-step esterification and transesterification were used. FTIR and GC remarked the biodiesels' existing functional groups and fatty acid methyl ester (FAME) composition. The thermal analysis of the biodiesel blends certified about the blends' stability regarding thermal degradation, melting and crystallization temperature, oxidative temperature, and storage stability. The brake power (BP), brake specific fuel consumption (BSFC), and brake thermal efficiency (BTE) of the biodiesel blends decreased slightly with an increasing pattern of nitric oxide (NO) emission. However, the hydrocarbon (HC) and carbon monoxides (CO) of biodiesel blends were found decreased.
This comprehensive paper conducts an in-depth review of personal exposure and air pollutant levels within the microenvironments of Asian city transportation. Our methodology involved a systematic analysis of an extensive body of literature from diverse sources, encompassing a substantial quantity of studies conducted across multiple Asian cities. The investigation scrutinizes exposure to various pollutants, including particulate matters (PM10, PM2.5, and PM1), carbon dioxide (CO2), formaldehyde (CH2O), and total volatile organic compounds (TVOC), during transportation modes such as car travel, bus commuting, walking, and train rides. Notably, our review reveals a predominant focus on PM2.5, followed by PM10, PM1, CO2, and TVOC, with limited attention given to CH2O exposure. Across the spectrum of Asian cities and transportation modes, exposure concentrations exhibited considerable variability, a phenomenon attributed to a multitude of factors. Primary sources of exposure encompass motor vehicle emissions, traffic dynamics, road dust, and open bus doors. Furthermore, our findings illuminate the influence of external environments, particularly in proximity to train stations, on pollutant levels inside trains. Crucial factors affecting exposure encompass ventilation conditions, travel-specific variables, seat locations, vehicle types, and meteorological influences. The culmination of this rigorous review underscores the need for standardized measurements, enhanced ventilation systems, air filtration mechanisms, the adoption of clean energy sources, and comprehensive public education initiatives aimed at reducing pollutant exposure within city transportation microenvironments. Importantly, our study contributes to the growing body of knowledge surrounding this subject, offering valuable insights for policymakers and researchers dedicated to advancing air quality standards and safeguarding public health.
The simulation of the catalytic converter system is quite needed in order to characterize the catalyst and also
optimizing the monolithic design for the gas emission in the catalytic converter and other related mechanism. The
objective of this study is to obtain quantitative description of the gas emission in the catalytic converter system of
natural powered automobile exhaust gas using ANSYS Software. This work will present a finite element calculation
to predict and evaluate the mass transfer, energy balance and velocity of gas emission in the catalytic converter. The
expected result for this research is to evaluate data of the gas emission obtained from the software to be compared with
the manual experiment in order to verify the effectiveness of modified catalytic converter.
Vegetable oil has become more attractive recently because of its environmental benefits and better
quality exhaust emission. A well-known transesterification process made biodiesel, pungam seed oil was selected for biodiesel production. Pungam seed oil is non-edible oil, thus, food versus fuel conflict will not arise if this is used for biodiesel production. A maximum of 75% biodiesel was produced with 20% methanol in the presence of 0.5% sodium hydroxide. The experimental investigations were carried out in an engine that is coupled with an eddy current dynamometer. The engine is a single cylinder water-cooled, direct injection diesel engine developing a power output of 3.7 kW at 1500 rev/min. The crank angle encoder measured the engine speed, whereas the piezo electric sensors measured the cylinder pressure and the fuel injection pressure. The experimental investigations were carried out for bio-diesel and diesel and the results were compared. From the experimental results, it is concluded that the use of bio-diesel as an alternative fuel leads to significant reduction in emissions and improved performance of diesel engines. This paper discusses the production process of biodiesel from Pungam seed oil and its performance in the compression ignition engine.
Increasing the range of vehicles on traffic roads in the urban area has led to traffic-related air pollution (TRAP) and is currently becoming the main concern for health, especially among children. The study aimed to determine associations between TRAP and respiratory health, also to identify the main factors that influenced them. A cross-sectional comparative study was carried out among children in high and low traffic areas. Air quality monitoring was conducted in six primary schools. A set of standardized questionnaires was distributed to obtain respondents' exposure history and respiratory health symptoms, while spirometry test was carried out to determine the lung function status. There were associations between TRAP and abnormality of FEV1% among children. NO2 was the main predictor that influenced both chest tightness and abnormality of FEV1%. Children exposed to a high level of traffic-related air pollution have an increased risk of respiratory symptoms and abnormality of lung function.
Diesel engines produce high emissions of nitrogen oxide, smoke and particulate matter. The challenge is to reduce exhaust emissions but without making changing their mechanical configuration. This paper is an overview of the effect of natural gas on the diesel engine emissions. Literature review suggests that engine load, air-fuel ratio, and engine speed play a key role in reducing the pollutants in the diesel engine emissions with natural gas enrichment. It is found that increasing the percentage of natural gas (CNG) will affect emissions. Nitrogen oxide (NOx) is decreased and increased at part loads and high loads respectively when adding CNG. The reduction in carbon dioxide (CO2), particulate matter (PM) and smoke are observed when adding CNG. However, carbon monoxide (CO) and unburned hydrocarbon (HC) are increased when CNG is added.
Automobile exhaust emission control is one of the trending issues in automobile research field. It caused by high
pollution such as carbon monoxide (CO), nitrogen oxides (NOx), and hydrocarbons (HC) distributed by automobile
especially form diesel engine. These pollutants give a harmful effect to the environment and human health. Therefore,
this paper proposed in reviewing methods on fabrication of modified catalytic converter. FeCrAl is used as substrate
which treated using ultrasonic bath technique which could improve the exhaust emission control. This metallic catalytic converter used as the replacement of precious metal that have high production cost.
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.
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.
In this study, Sulphated/AlMCM-41 (S/AlMCM-41) catalysts were synthesized and used to produce biodiesel from CFMO. Different percentages of S/AlMCM-41 catalysts were prepared and characterized by X-ray diffraction, BET studies, TPD, and SEM-EDS analysis. Sulphur incorporation to the MCM framework though reduced the surface area, and pore volume of the catalyst, sufficient acidity were produced in the catalyst surface. The existence of functional groups and the composition of the biodiesel obtained was analysed by FTIR and GC-MS. S/AlMCM-41 (80%) catalyst presented a high catalytic activity with maximum biodiesel conversion % when compared to other variants. The bio-ester produced from CFMO with S/AlMCM-41 (80%) catalyst possessed the higher calorific value of 50 MJ/kg and flashpoint of 153 °C and other properties analogous to the standard biodiesel. The engine performance was examined for biodiesel blends with neat diesel, where biodiesel blends performed better than neat diesel. The exhaust gas emission studies also highlighted that the obtained biodiesel showed emission characteristics similar to the standard biodiesel, whereas marginally higher emission for CO and CO2 of about 2.2 and 7.9% was reported.
To date, the development of renewable fuels has become a normal phenomenon to solve the problem of diesel fuel emissions and the scarcity of fossil fuels. Biodiesel production has some limitations, such as two-step processes requiring high free fatty acids (FFAs), oil feedstocks and gum formation. Hydrotreated vegetable oil (HVO) is a newly developed international renewable diesel that uses renewable feedstocks via the hydrotreatment process. Unlike FAME, FFAs percentage doesn't affect the HVO production and sustains a higher yield. The improved characteristics of HVO, such as a higher cetane value, better cold flow properties, lower emissions and excellent oxidation stability for storage, stand out from FAME biodiesel. Moreover, HVO is a hydrocarbon without oxygen content, but FAME is an ester with 11% oxygen content which makes it differ in oxidation stability. Waste sludge palm oil (SPO), an abundant non-edible industrial waste, was reused and selected as the feedstock for HVO production. Techno-economical and energy analyses were conducted for HVO production using Aspen HYSYS with a plant capacity of 25,000 kg/h. Alternatively, hydrogen has been recycled to reduce the hydrogen feed. With a capital investment of RM 65.86 million and an annual production cost of RM 332.56 million, the base case of the SPO-HVO production process was more desirable after consideration of all economic indicators and HVO purity. The base case of SPO-HVO production could achieve a return on investment (ROI) of 89.03% with a payback period (PBP) of 1.68 years. The SPO-HVO production in this study has observed a reduction in the primary greenhouse gas, carbon dioxide (CO2) emission by up to 90% and the total annual production cost by nearly RM 450 million. Therefore, SPO-HVO production is a potential and alternative process to produce biobased diesel fuels with waste oil.
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.
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.
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.
The availability of natural energy resources and the environmental issues are the most significant issues that are often highlighted by the world communities. With regard to these problems, isobutanol is a higher chain alcohol with four carbons which can be derived from biomass resources and it is potential to become an alternative fuel source besides the biodiesel for a diesel engine. The aim of this study is to evaluate the effect of isobutanol with Calophyllum inophyllum methyl ester and diesel as the ternary blend on physicochemical properties, engine performance, and emission characteristics. Five different fuel blends containing Calophyllum inophyllum biodiesel and isobutanol were tested on a single-cylinder direct injection diesel engine at different engine load of brake mean effective pressure. The physicochemical properties of the fuel blends were measured and then compared with neat diesel. The results indicate that the blend containing isobutanol and CIME gives a slight increase in BSEC and EGT and a minimal drop in BTE as compared to that of neat diesel. Besides that, the tested blends show a reduction of carbon monoxide and unburned hydrocarbon emissions. Meanwhile, all the fuel blends show a minimal increase in carbon dioxide and nitrogen oxides emissions, compared to that of neat diesel. Isobutanol can be proved as a preferred substitute for biodiesel and diesel fuels to achieve desired engine performance and emissions level.
The aim of the present study was to investigate the potential sources of heavy metals in fine air particles (PM2.5) and benzene, toluene, ethylbenzene, and isomeric xylenes (BTEX) in gas phase indoor air. PM2.5 samples were collected using a low volume sampler. BTEX samples were collected using passive sampling onto sorbent tubes and analyzed using gas chromatography-mass spectrometry (GC-MS). For the lower and upper floors of the evaluated building, the concentrations of PM2.5 were 96.4 ± 2.70 μg/m3 and 80.2 ± 3.11 μg/m3, respectively. The compositions of heavy metals in PM2.5 were predominated by iron (Fe), zinc (Zn), and aluminum (Al) with concentration of 500 ± 50.07 ng/m3, 466 ± 77.38 ng/m3, and 422 ± 147.38 ng/m3. A principal component analysis (PCA) showed that the main sources of BTEX were originated from vehicle emissions and exacerbate because of temperature variations. Hazard quotient results for BTEX showed that the compounds were below acceptable limits and thus did not possess potential carcinogenic risks. However, a measured output of lifetime cancer probability revealed that benzene and ethylbenzene posed definite carcinogenic risks. Pollutants that originated from heavy traffic next to the sampling site contributed to the indoor pollution.
Climate change and global warming as the key human societies' threats are essentially associated with energy consumption and CO2 emissions. A system dynamic model was developed in this study to model the energy consumption and CO2 emission trends for Iran over 2000-2025. Energy policy factors are considered in analyzing the impact of different energy consumption factors on environmental quality. The simulation results show that the total energy consumption is predicted to reach 2150 by 2025, while that value in 2010 is 1910, which increased by 4.3% yearly. Accordingly, the total CO2 emissions in 2025 will reach 985million tonnes, which shows about 5% increase yearly. Furthermore, we constructed policy scenarios based on energy intensity reduction. The analysis show that CO2 emissions will decrease by 12.14% in 2025 compared to 2010 in the scenario of 5% energy intensity reduction, and 17.8% in the 10% energy intensity reduction scenario. The results obtained in this study provide substantial awareness regarding Irans future energy and CO2 emission outlines.
This is the first publication on the distribution and sources of polycyclic aromatic hydrocarbons (PAHs) in riverine and coastal sediments in South East Asia where the rapid transfer of land-based pollutants into aquatic environments by heavy rainfall and runoff waters is of great concern. Twenty-nine Malaysian riverine and coastal sediments were analyzed for PAHs (3-7 rings) by gas chromatography mass spectrometry. Total PAHs concentrations in the sediment ranged from 4 to 924 ng/g. Alkylated homologues were abundant for all sediment samples. The ratio of the sum of methylphenanthrenes to phenanthrene (MP/P), an index of petrogenic PAHs contribution, was more than unity for 26 sediment samples and more than 3 for seven samples for urban rivers covering a broad range of locations. The MP/P ratio showed a strong correlation with the total PAHs concentrations, with an r2 value of 0.74. This ratio and all other compositional features indicated that Malaysian urban sediments are heavily impacted by petrogenic PAHs. This finding is in contrast to other studies reported in many industrialized countries where PAHs are mostly of pyrogenic origin. The MP/P ratio was also significantly correlated with higher molecular weight PAHs such as benzo[a]pyrene, suggesting unique PAHs source in Malaysia which contains both petrogenic PAHs and pyrogenic PAHs. PAHs and hopanes fingerprints indicated that used crankcase oil is one of the major contributors of the sedimentary PAHs. Two major routes of inputs to aquatic environments have been identified: (1) spillage and dumping of waste crankcase oil and (2) leakage of crankcase oils from vehicles onto road surfaces, with the subsequent washout by street runoff. N-Cyclohexyl-2-benzothiazolamine (NCBA), a molecular marker of street dust, was detected in the polluted sediments. NCBA and other biomarker profiles confirmed our hypothesis of the input from street dust contained the leaked crankcase oil. The fingerprints excluded crude oil, fresh lubricating oil, asphalt, and tire-particles as major contributors.