Papers by Keyword: Binary System

Abstract: Conventional cement production process emits tons of carbon dioxide gas which is one of the greenhouse gases that influence the environment across the world. Discovering the alternative construction material with the eco-friendly process and the performance similar to or greater than ordinary Portland cement has been attractive to find out. This research presented green construction materials or so-called geopolymers from metakaolin substituted by high calcium fly ash by 20, 40, 60, 80 and 100 wt%. Some researches reported that geopolymer produced from metakaolin and fly ash with alkali solution gave a great result, but usually, they used fly ash containing very low calcium component. Compressive strength at 3, 7 and 28 curing days and flowability were conducted. The compressive strength of geopolymers blended with high calcium fly ash was still developed as the curing day increased and revealed the highest at 28 days especially on MK40 (high calcium fly ash 60 wt%). Geopolymer pastes prepared with a higher amount of high calcium fly ash exhibited less viscous. It was proved that the high amount of high calcium fly ash could be applied and gave extraordinary compressive strength. Furthermore, X-ray diffraction and X-ray fluorescence were used to investigate chemical properties as well as microstructure by a scanning electron microscope. For phase analysis, the existence of oxides of calcium and sulfur in high calcium fly ash resulted in the formation of thenardite, calcite, portlandite and C-S-H phase associating with geopolymeric phase. Therefore, this research proposed the opportunity for geopolymer production by using abundant high calcium fly ash to raise the value of the industrial waste products and green alternative construction material compared with OPC.

Abstract: The biosorption of cadmium and lead by Penicillium sp. isolated from an uncontaminated soil was studied at different initial metal ions concentrations. The maximum removal yields were obtained at 5 mg/L initial metal concentration. The highest removal yields were 35.67% and 81.99% for cadmium and lead respectively in the single system. In the binary system, the removal yield increased to 90.99% and 97.48% for both metal ions at the same initial concentration. This study has also confirmed that Penicillium sp was able to grow in the presence of both metal ions at different concentrations. In addition, this study showed that Penicillium sp was more tolerant to cadmium than lead. Fungi have also shown a tolerance to high concentrations of toxic heavy metals.This study can provide useful information on the bioremoval of heavy metals such as Cd(II) and Pb(II) from wastewaters.

Abstract: In this study, a mathematical model is constructed to calculate the forces of a single copper particle on the silicon surface in CO₂+solvent systems. The equilibrium separation distance (ESD) and net adhesion force (NAF) are used to discriminate the difficulty of particle removal. In general,the bigger the NAF is, the more difficult the cleaning is. Series values of ESD and NAF are obtained by altering the particle radius, temperature, pressure and solvent type. The value of NAF decreases with the increase of pressure and increases with the increase of the particle radius. When the particle radius is 110 nm, the variations of ESD and NAF with system pressure in CO₂+acetone system indicate that, the ESD always exhibits a maximum in the regions of temperature range (303.15-323.15K) and higher pressure could facilitate the particle removal. When the pressure is super high, the lower temperature get the smaller NAF. Besides, the variations of ESD and NAF with system pressure are gained from the contrastive analysis of three different solvents including acetone, isopropanol and methanol at 313.15K. The calculation results indicate that acetone and isopropanol, especially the isopropanol,have good particle removal abilities with respect to methanol which NAF value is biggest and tends to be unstable.

Abstract: An experimental validation on laboratory scale has been conducted to investigate and to compare two thermodynamic cycles, Trilateral Flash Cycle (TFC) and Organic Rankine Cycle (ORC). The research covers the heat engine utilizing a hydrothermal resource to compare the performance of TFC and ORC. This research would help to analysis the thermal efficiency and power efficiency for both cycles. TFC shows a higher power production than in ORC for the same applied parameters. ORC, however, can be operated at lower rotational speed than for TFC. This project could help, also, to evaluate the current two phase screw expander for both cycles. It is concluded to propose a larger heat exchanger for TFC as the heat recovery can be more reliable in this cycle than in ORC. This research can be applied to generate electrical power from hydrothermal resources such as geothermal energy and solar thermal.

Abstract: Ionic liquid (IL) N-methyl-N-methylimidazoliumdimethyl phosphate ([DMIM][DMP]) and active carbon (AC) binary system were established and demonstrated to be effective for the deep removal of sulfur compounds (Dibenzothiophene, DBT) from model oil at room temperature. Mass ratio of IL to active carbon on the extractive performance, desulfurization temperature, time and desulfurization reagent to model oil were investigated. In the first stage desulfurization efficiency of binary system, IL and active carbon were 65.09%, 51.72% and 47.3%，which was followed the order of binary system > IL > active carbon. It was suitable to carried out desulfurization process with mass ratio of IL to active carbon in 1:1, binary system to model oil in 1:1 for 10 min at 25-45oC. In the optimiazed condition, desulfurization efficiency of binary system was nearly 100% after the fifth stage desulfurization process.

Abstract: Although biosorption for reclaiming single precious metal was frequently reported, the actual subsistent adsorptive competition among different metal ions sometimes shows diverging reinforcement or prohibition for different species. This study tries to screen bacteria that are able to absorb certain precious metals with high selectivity under competitive conditions. The activated sludge was cultivated from enrichment by magnetotactic bacteria medium proposed by Blakemore. Then four microbes, microaerobic bacteria(A) acclimated micro-aerobic bacteria (B), anaerobic bacteria(C) and acclimated anaerobic bacteria(D) were obtained for the following adsorption experiments. The four microbes have high removal efficiency of Au3+ both in its unitary and Au³⁺-Cu²⁺ binary system. The microaerobic bacteria (B) are good metal catchers and carriers for the uptake of gold in aquatic solution with coexistence of copper. In Pd²⁺-Cu²⁺system, there is a collaborative adsorption effect, especially on (B).

Abstract: Solid-solid phase change material can increase the thermal storage capacity of the wall, decrease the indoor temperature fluctuation and building energy consumption when it was used in the phase change material (PCM) wall. This paper investigated experimentally the phase change temperature and latent heat of polyalcohols binary system with different component, and analyzed the feasibility of phase change wall. The results show that binary systems have suitable phase change temperature and bigger phase change latent. They are ideal phase change materials used in the wall.