Chodchanok Attaphong

Adsorption and adsolubilization of polymerizable surfactants on aluminum oxide.

Surfactant-based adsorption processes have been widely investigated for environmental applications. A major problem facing surfactant-modified adsorbents is surfactant loss from the adsorbent due to loss of monomers from solution and subsequent surfactant desorption. For this study, a bilayer of anionic polymerizable surfactant (Hitenol BC 05, Hitenol BC 10 and Hitenol BC 20) and non-polymerizable surfactant (Hitenol N 08) was adsorbed onto alumina. The results of adsorption studies showed that as the number of ethylene oxide (EO) groups of the surfactants increased, the area per molecule increased and the maximum adsorption decreased. The lowest maximum adsorption onto alumina was for Hitenol BC 20 (20 EO groups) corresponding to 0.08 mmol/g or 0.34 molecule/nm(2) while the highest level of adsorption was 0.30 mmol/g or 1.28 molecule/nm(2) for Hitenol BC 05 (5 EO groups). This variation in adsorption was attributed to the increased bulkiness of the head group with increasing number of EO groups. Relative to the adsolubilization capacity of organic solutes, ethylcyclohexane adsolubilizes more than styrene. Styrene and ethylcyclohexane adsolubilization were both independent of the number of EO groups of the surfactant. For surfactant desorption studies, the polymerization of polymerizable surfactants increased the stability of surfactants adsorbed onto the alumina surface and reduced surfactant desorption from the alumina surface. These results provide useful information on surfactant-based surface modification to enhance contaminant remediation and industrial applications.

Phase behaviors, fuel properties, and combustion characteristics of alcohol-vegetable oil-diesel microemulsion fuels

ABSTRACT Biofuels are being considered as alternatives to fossil-based fuels due to depletion of petroleum-based reserves and pollutant emission concerns. Vegetable oils and bioalcohols have proven to be viable alternative fuels both with and without engine modification. However, high viscosity and low energy content are long-term operational problems with vegetable oils and bioalcohols, respectively. Therefore, vegetable oil-based microemulsification is being evaluated as a method to reduce the high viscosity of vegetable oils and enhance the miscibility of alcohol and oil phases. Studies have shown that microemulsification with different alcohols lead to varying fuel properties depending on their structure. The overall goal of this study was to formulate microemulsion fuels with single and mixed alcohol systems by determining the effects of water content, alcohol branching structure and carbon chain length on phase behaviors, fuel properties, and emission characteristics. It was found that microemulsion fuels using certain alcohols displayed favorable stability, properties, and emission characteristics. Flames of fuels with linear short-chain-length alcohols had larger near-burner blue regions and lower CO and soot emissions indicating the occurrence of more complete combustion. In addition to alcohol effects, the effect of vegetable oils, surfactants, and additives on emission characteristics were insightful in pursuit of appropriate microemulsion fuels as cleaner burning alternatives to both No.2 diesel and canola biodiesel.

Combustion Properties of Jet A/Ethanol Blends in a Porous Media Burner

Porous media combustion has several advantages including increased heat transfer from product gases to reactants, improved combustion efficiency and reduced pollutant emissions. Ethanol is a renewable biofuel which can be blended with petroleum-based fuels. In this study, the combustion properties of a 10% (by volume) ethanol blend with Jet A in a porousmedia burner are compared with those of pure Jet-A. Five injector-exit equivalence ratios were studied: 0.2, 0.41, 0.67, 0.8 and 0.96. The global NOx emissions, concentrations of CO2 and O2 in exhaust, global temperature of exhaust, and radial temperature profiles at 50% flame height were measured. The flame heights of the ethanol-blend flames were smaller than those of Jet A by 10 -20%. The NOx emission index and the global temperature of the ethanol-blend flames were higher than those of the Jet-A flame. At an equivalence ratio of 0.4, the temperatures at mid-flame of the ethanol-blend flame were lower than those of JetA; the differences in temperature were negligible at an equivalence ratio of 0.8.

Effect of additives on fuel properties and emission characteristics of micromulsion biofuels from palm oil

Microemulsiflcation is one of the novel techniques to reduce viscosity of vegetable oils to avoid durability problems in diesel engines. Microemulsion biofuels are transparent, thermodynamically stable, and single-phase mixtures of vegetable oils and ethanol in the presence of surfactants and co-surfactants. Additives have also been included in microemulsion biofuel formulations to improve their stability and fuel properties; however, there is limited research on the effect of additives on emission characteristics of microemulsion biofuels. In this study, microemulsion biofuels were formulated from palm oil/diesel blend (1:1 v/v), ethanol, surfactant, and co-surfactants. Five additives, ethylene glycol butyl ether (EGBE), diethylene glycol ethyl ether (DEGEE), propylene glycol ethyl ether (PGEE), dipropylene glycol methyl ether (DPGME), and ethyl acetate (EA), were used to study the effect of additives on phase behaviors, fuel properties, and emission characteristics. The results showed that studied additives could improve some fuel properties of microemulsion biofuels with negligible effect on phase stability. Additionally, it was found that carbon monoxide (CO) emissions from microemulsion biofuels with DEGEE and EA, and nitrogen oxide (NOx) emissions from microemulsion biofuels with all additives were lower than those from diesel and biodiesel. Therefore, DEGEE and EA can be considered as promising additives for microemulsion biofuel formulations, which can improve fuel properties as well as can significantly reduce CO and NOx emissions below the levels of diesel and biodiesel. These encouraging results offer options of additives for biofuel applications.

Phase behaviors and fuel properties of palm oil-based microemulsion biofuels using sugar-based surfactants

Due to environmental concerns and current fossil-fuel situations, palm oil has been considered as a potential vegetable oil for renewable biofuel applications in South East Asia. To solve durability problems in diesel engine caused by high viscosity of palm oil, microemulsification has led to more attention as a novel viscosity-reducing technique. Microemulsion biofuels are transparent, thermodynamically stable, and singlephase microemulsions, where the polar phase is solubilized in surfactant aggregates existing in the non-polar phase. Surfactants (surface active agents) play a key role in enhancement of the interaction between polar and non-polar phases. Since sugar-based surfactants have been derived from bio-based resources, they have been introduced to formulate microemulsion biofuels in this study. Three sugar-based surfactants, sorbitan monolaurate (SM20), sorbitan monooleate (SM80), and sorbitan trioleate (ST85) and three alcohols (butanol, hexanol, and octanol) were used as surfactants and co-surfactants, respectively. The objectives of this study are to formulate microemulsion biofuels using sugar-based surfactants, to study the effects of surfactants and co-surfactants on phase behaviors and kinematic viscosities, and to investigate the effect of surfactant/co-surfactant ratio on other fuel properties (i.e. energy content, cold flow properties, density, and ash content). The results show that the microemulsion system using SM80 and octanol at the molar ratio of 1 to 8 was considered as an optimized microemulsion biofuel formulation demonstrating comparable fuel properties to biodiesel. These results provide useful guidance for future design of environmentally friendly microemulsion biofuels.

Analyzing technique for electrical energy monitoring system in Thailand hospital

An electrical energy monitoring system helps improve the security and reliability of a hospital operating system which can also indirectly enhance energy efficiency itself. However, a large hospital has a complex electrical system which leads to the big data issue from the installed monitoring system in this size-scaled hospital. Therefore, this paper proposes K-mean clustering technique, which is one of the effective data mining techniques, to analyze the big data from the electrical energy monitoring system in hospital. The case study is a large hospital with 200 in-patient beds in Thailand. Without loss of generality, electrical load profile is used for analyzing instead of using the electrical energy. Finally, the proposed data clustering technique is able to characterize electrical load profiles effectively for each hospital floor. This technique also identify the abnormality of these characterized electrical load profiles in various scenarios which hospital system operators can use them to consider the security, reliability, and energy efficiency of their operating systems.