Desorption characteristics of VOCs were investigated for the effective recovery of gasoline vapor. The adsorption capacity and desorption capacity were excellent at relatively low temperatures. The differences in the desorption capacity were not large in the condition; desorption temperature 25℃, desorption pressure 760 mmHg, inlet air flow rate 0.5 L/min, but were relatively great in the condition; desorption temperature 0℃, desorption pressure 60 mmHg, inlet air flow rate 1.0 L/min. The desorption ability of pentane was increased to about 81.4%, and the desorption ability of hexane was increased to about 102%, also the desorption ability of toluene was increased to about 156.7% by changes of temperature, pressure, inlet air flow rate in the experimental conditions. The optimum desorption condition for the effective recovery of VOCs was in the conditions; desorption temperature 0℃, desorption pressure 60 mmHg, inlet air flow rate 1.0 L/min.

The purpose of this work is to study the adsorption and desorption characteristics of acetone vapor and toluene vapor from adsorption tower in the VOCs recovery device. The six kinds of activated carbon with different pore structures were used and the adsorption and desorption characteristics were compared according to pore structure, desorption temperature, and adsorption method, respectively. Adsorption capacity of acetone vapor and toluene vapor by batch method was higher than that by dynamic method. Especially, activated carbon with medium-sized or large pores had more difference in adsorption capacity according to adsorption methods as a result of gradually condensation of vapors on relatively mesopore and large pores. Activated carbons with relatively large pores and relatively small saturated adsorption capacity had excellent desorption ability.

Cereal seeds, sorghum, foxtail millet, hog millet, adlay, and corn are traditionally used as health assistant as well as energy supplying food in Korea. While beneficial phytochemicals to human have revealed in cereals, the information on peptides from cereals is far less accumulated than major reserve protein. Here, we analyzed peptide profiles using surface enhanced laser desorption/ionization time of flight mass spectrometry (SELDI-TOF MS) in cereal seeds for construction of peptide information and attempted to develop peptide biomarkers for cereal identification. To optimize the analysis condition of SELDI-TOF MS, the effect of dilution factor on binding affinity to protein chips was tested using CM10 and Q10 arrays. Peptide clusters were significantly different at the level of 0.01 p-value. Peak spectra were the most stable in 1:50 of dilution factor in both chip arrays. Numbers of detected peak of 5 cereal seeds were 131 in CM10 and 74 in Q10 array. Each cereal was grouped as a cluster and well discriminated into different cluster in the level of 0.01 p-value. Numbers of potentially identified peptide biomarkers are 11, 13, 9, 5 and 12 in sorghum, foxtail millet, hog millet, adlay and corn, respectively. This study demonstrates that each cereal seed have own distinguishable specific peptides although their function are not identified yet in this study. In addition, the proteomic profiling using SELDI-TOF MS techniques could be a useful and powerful tool to discover peptide biomarker for discrimination and assess crop species, especially under 20 kDa.

This paper describes the adsorption/desorpton efficiency of a modified activated carbon by irradiated microwave to treat toluene. By employing microwave energy, the regeneration time was considerably shortened compared with conventional thermal heating regeneration. New adsorbent called ACB(Activated Carbon-Bentonite) was prepared from powder activated carbon with mixing bentonite as a binder. Specific surface area, average pore size and total pore volume of ACB were calculated from the nitrogen adsorption/desorption isotherm. The surface of ACB was characterized with scanning electron microscope(SEM). The results showed that the specific surface area, total pore volume, average pore size of ABC was not influenced by regenerating cycle with microwave irradiation. Toluene was adsorbed onto ACB which desorbed by MW irradiation. Absorption capacity of ACB was 0.117 gtoluene/ gACB. Desorption efficiency of toluene increased as higher microwave output was applied.

This study was performed : 1) to establish the experimental analysis conditions for the sorption and desorption of toxic organic contaminants to/from the activated sludge, sediment, and clay, and 2) to determine the sorption and desorption equilibrium coefficients of some representative halogenated aliphatic compounds. Through the preliminary sorption test using Azo dye, a setting of quantitative experimental conditions to determine the sorption and desorption characteristics was decided as follows; equilibration time of 180 minutes, centrifuge for 15 minutes at 5000×g, and 500㎎/ℓ of TOC concentration. The sorption and desorption characteristics of halogenated aliphatic compounds onto activated sludge, sediment and clay could be described very well using the Freundlich isotherm. The preference of the average sorption capacity of the overall compounds showed in the sequence sediment 0.26㎎/g, clay 0.23㎎/g, and activated sludge 0.11㎎/g. The desorption rate of the sorbed compounds onto activated sludge, sediment and clay was approximately 89.8%, 35.3%, and 66.4%, respectively.

Laboratory experiments were conducted to examine the behavior of metalaxyl in environment, which was used as pesticide in green soil of golf course and as functions of the characteristics of adsorption, desorption and degradation in soil texture and organic matter contents. Acid water containing metalaxyl was conducted to evaluate the effects on adsorption, desorption and degradation. The adsorption of metalaxyl played more significant role in organic contents than clay contents, and pH increases more pH 2.5 than pH 5.6. The desorption of metalaxyl from contaminants soil decreased higher organic contents LS-soil than S-soil, but the desorption amount of metalaxyl increased more pH 5.6 than pH 2.5. The rate of degradation of metalaxyl in green soil environmental increased higher organic contents LS-soil than S-soil and decreased more pH 2.5 than pH 5.6. These results indicated that the behavior of metalaxyl of the green soil was affected the soil texture of the golf course. Increasing of organic contents, the adsorption amount of metalaxyl on soil increased. Moreover, the decrease of the pH of solution increased adsorption amounts and decreased desorption amounts. As the results, the transportation of metalaxyl in soil decreased the acidic rates. The acidification of soil by the acid rain increased the adsorption amount of metalaxyl, but the degradation of metalaxyl decreased. Therefore, it is possible to sustain contamination in run-off the stream and ground water by residuals in soil.

The biosorption and desorption of Cd were carried out using brown marine algae, known as the good biosorbent of heavy metals. The content of alginate bound to light metals could be changed by the physical and the chemical pretreatment of Sargassum fluitans biomass. The Cd uptake was independent of the alginate content. In case of protonated biomass, Cd uptake was the lowest because the alginic acid of biomass was dissolved to cadmium solution during the biosorption. The maximum Cd uptake of Sargassum biomass was ranged from 79㎎/g to 139㎎/g. In case of raw biomass, the higher the alginate content of biomass, the higher was the Cd uptake. 100% of Cd and light metals sorbed in the biomass were eluted at 0.1N HCl(pH 1.1). However, the elution efficiency in CaCl2 and Ca(NO3)2 solution was varied by the concentration, the solid to liquid ratio and the pH of calcium solution. The distribution coefficient between Cd and protons in the desorption solution at pH ranged from 1.6 to 2.9 was observed on the constant stoichometric coefficient(1.3).

In order to investigate the effects of pH and organic matter content on cadmium adsorption and exchangeable cations desorption in soils, the adsorption isotherms of cadmium and the desorption isotherms of calcium and magnesium on four New Jersey soils at four pH values were plotted, and the cadmium partition coefficients (Kd) were also calculated. The slopes of cadmium adsorption isotherms dramatically increased with increasing solution pH. Judging from Langmuir adsorption equations, the maximum adsorption quantities (b) of cadmium at high pH values were much greater than those at low pH values for the same soil. The partition coefficients increased greatly with increasing solution pH. The slopes of regression equations between partition coefficients and pH values were steep in the order of the organic matter content of the soils. The correlation coefficients (r^2) between partition coefficient and organic matter content for 1 × 10 exp (-4) M increased from 0.3027 at pH 4.0 to 0.9964 at pH 8.5 and from 0.2093 at pH 4.0 to 0.9657 at pH 8.5 for 2×10 exp(-4) M Cd (NO3)2. The desorption quantities of calcium and magnesium decreased with increasing solution pH and increased with increasing cadmium adsorption.