The present work reports the effect of different functionalization methodologies on surface modification of porous carbon and its efficacy for benzene adsorption. The virgin and surface-modified adsorbents were characterized by FTIR, N2 sorption analysis, SEM, and Boehm titration. The adsorption isotherms were measured at different temperatures using a highly sensitive magnetic suspension microbalance. At lower benzene concentration, the virgin carbon was found to possess reasonable adsorption capacity, while at higher benzene concentration, the surface-modified carbon tends to perform better. The maximum benzene adsorption capacity at 25 °C and vapor pressure of 90 mbar is as follows: 467 mg/g (NORIT-AC), 227 mg/g (AC-APS (1 M)), 388 mg/g (Norit-AC-HT), 492 mg/g (AC-HNO3), and 531 mg/g (AC-H2SO4).

n-Nonane, 1¸2¸4-trimethylbenzene (124-TMB), toluene, total xylene (TXYL), isopropyl alcohol (IPA), and methyl ethyl alcohol (MEK) are major volatile organic compounds (VOCs) emitted from printing industries. The absorption amount of a single VOC per unit weight of silicone oil was as follows in the order of 189.5 g/kg-silicone oil for n-nonane, 91.7 g/kg-silicone oil for 124-TMB, and 60.1 g/kg-silicone oil for TXYL. Although hydrophobic VOCs were more absorbed in silicone oil than hydrophilic VOCs such as IPA and MEK, IPA and MEK, which had log Kow values of 1 or less, also were absorbed more than 26.0 g/kg-silicone oil. In two and three mixed VOCs of n-nonane, 124-TMB, and toluene, the absorption amount of each in silicon oil was less than that of single a VOC. The total absorption amount of two mixed VOCs ranged from 47.9 g to 138.7 g/kg-silicone oil, and the total absorption amount of three mixed VOCs was 65.8 g/kg-silicone oil. These results suggest that silicone oil is a promising pretreatment solution capable of absorbing high concentrations of VOCs that are intermittently emitted from printing industries. The absorption information of VOCs obtained in this study can be used as the design parameters of a damping device for the pretreatment of VOCs.

The efficiency of using 7 indoor plants, which were Chrysalidocarpus lutescens, Ficus robusta, Sansevienria trifasciata, Rhapis excelsa, Scindapusus aureus, Anthurium andraeanum and Pachira aquatica, for B·T·E (Benzene, Toluene, Ethylbenzene) removal were assessed at 1200 Lux light intensity in airtight chambers (1.27 m3). Rhapis excelsa, Chrysalidocarpus lutescens and Ficus robusta were among the most effective plants, completely removing for B·T·E within 38 hours, wherease Scindapusus aureus and Sansevienria trifasciata were the lowest in terms of removal efficiency. But when the removal efficiency was measured per unit leaf area (μg·m−3·−2), it was found that Scindapusus aureus, Anthurium andraeanum and Sansevienria trifasciata removed higher amount than Rhapis excelsa, Chrysalidocarpus lutescens and Ficus robusta. Plants with wide leaves and a big leaf area including Rhapis excelsa and Chrysalidocarpus lutescens showed higher removal efficiencies of B·T·E than those with smaller leaves such as Scindapusus aureus. Among the plants tested over 120 hours, the species that emitted the highest levels of CO2, involved with photosynthesis and respiration in plants, Pachira aquatica (11,560 ppm) was emitting 10 times more CO2 than Scindapusus aureus (1,260 ppm).

Benzene was oxidized by binary oxidants composed of nitric acid and hydrogen peroxide at 80℃. The product obtained was analyzed with gas chromatograph-mass spectrometer. Eight high value compounds, 2-nitrophenol, 2-chloro-6-nitrophenol, 4-chloro-2- nitrophenol, 2-chloro-4-nitrophenol, 2,4-dinitrophenol, 4-nitrophenol, 2,6-dinitrophenol and 2-chloro-4,6-dinitro-phenol were found, which they have high contents in the range from 4.28% to 32.52%. These compounds are very widely used in organic synthesis. e.g., synthesizing dye, medicines and chemical reagents, pesticide, explosive, polymer, etc.

A series of noble poly(amide-imide)s and copoly(amide-imide)s bearing 1,2-bis(4-phenoxy)benzene units were synthesized by the direct polycondensation of 1,2-bis(4-trimellitimidophenoxy)benzene[1,2-PTPB] with a combination of commercially available aromatic diamines and diacids such as m-phenylene diamine, p-phenylene diamine(PPD), isophthalic acid and terephthalic acid(TA) in N-methyl-2-pyrrolidone(NMP) using triphenyl phosphite and pyridine as a condensing agent in the presence of dehydrating agent (CaCl2). The resulting polymers had inherent viscosities in the range of 0.37~0.78 dL/g and most of them were soluble m common organic solvents including NMP, dimethylacetamide, dimethylsulfoxide, dimethylformamide, and m-cresol. Wide-angle X-ray diffractograms revealed that the copoly(amide-imide) derived from PPD with mixed acids of 1,2-BTPB and TA, showed crystalline nature, whereas all of the other polymers were found to be amorphous. The glass transition temperatures of the polymers occurred over the temperature range of 270~323℃ in their differential scanning calorimetry curves and their 10% weight loss temperature, determined by thermogravimetric analysis in air and nitrogen atmosphere, were in the range 465~535℃, 500~550℃, respectively, indicating their good thermal stability.

Oxidation characteristics of benzene as a VOC were investigated using a fixed bed reactor system over transition metal catalysts. The transition metal catalysts were made by using transition metal nitrate reagent and various support materials such as γ-Al2O3, and TiO2. The parametric tests were conducted at the reaction temperature range of 200～500℃, benzene concentration of 2,000～3,000 ppm with space velocity of 10000 hr-1. The property analyses such as BET, SEM, TGA and the conversions of catalytic oxidation of VOC were examined. The experimental results showed that the BET surface areas of catalyst are 86.4∼167.7m2/g, the pore volumes are 0.049∼0.056cm3/g, and the average pore sizes of catalyst are 27∼44Å, which mean the meso pore. It was also found that the conversion of benzene oxidation reaction at 400∼500℃ with Cu/γ-Al2O3+TiO2 catalyst showed 90∼100%, which indicate that the transition metal catalyst with composite supports is very effective for the oxidation of benzene.

Treatment characteristics of benzene were investigated by using a fixed bed reactor system applying a hybrid method over composites of photocatalyst and adsorbent. Various composites were made by mixing photocatalyst with adsorbent, such as activated carbon, activated carbon fiber, and sludge. Performance tests were conducted with benzene concentrations of 1,000～3,000 ppm, Benzene flow rates of 50～100cc/min, and packing weights of 14～24g for the various composite samples. The property of benzene treatment was analyzed concerning BET, SEM, pH, and the conversion efficiency. It was concluded by experimental results that the benzene conversion efficiency of a hybrid method was much higher than that of a photocatalyst only method showing a conversion efficiency range between 13% and 65%. It was also found that the comprehensive feasibility study of the hybrid method would be needed with consideration of various factors including additional expenses.

the less-reported gaseous studies have primarily dealt with chemical process stream concentrations than indoor air quality (IAQ) concentration levels. Accordingly, the current study was conducted to establish the feasibility of applying visible-light-induced TiO₂ doped with sulfur (S) element to cleanse toluene and ehtyl benzene at IAQ levels. The S-doped TiO₂ was prepared by applying two popular processes and two well-known methods. For both target compounds, the two coating methods exhibited different photocatalytic oxidation (PCO) efficiency. Similarly, the two S-doping processes showed different PCO efficiency. These results indicate that the coating method and doping process are important parameters which can influence PCO efficiency. Meanwhile, it was found that the PCO efficiency of ethyl benzene was higher than that of toluene. In addition, the degradation efficiency of the target compounds increased as the relative humidity (RH) decreased. The PCO efficiency varied from 44% to 74% for toluene and from 68% to 95%, as the RH decreased. Consequently, it is suggested that with appropriate RH conditions, the visible-light-assisted photocatalytic systems can also become an important tool for improving IAQ.

Characteristics of VOC(benzene) treatment were investigated using a fixed bed reactor system over copper base catalyst and photocatalyst/adsorbent blending material. The copper base catalysts were made by using copper nitrate reagent and various support materials such as γ-Al2O3, TiO2. The parametric tests were conducted at the reaction temperature range of 200～400℃, benzene concentration of 1,000～2,000 ppm, and space velocity range of 5,000～10,000 hr-1. The property analyses such as BET, SEM and the removal efficiency(conversion) of VOC were examined. The experimental results showed that the VOC removal efficiency of hybrid method was higher than that of single method. It was also found that the comprehensive feasibility study of hybrid method would need with considering various factors including additional expenses.

Molecular sieving carbon (MSC) for separating O2-N2 and CO2-CH4 has been prepared through chemical vapor deposition (CVD) of methane and benzene on activated carbon spheres (ACS) derived from polystyrene sulfonate beads. The validity of the material for assessment of molecular sieving behavior for O2-N2 and CO2-CH4 pair of gases was assessed by the kinetic adsorption of the corresponding gases at 25℃. It was observed that methane cracking on ACS lead to deposition of carbon mostly in whole length of pores rather than in pore entrance, resulting in a reduction in adsorption capacity. MSC showing good selectivity for CO2-CH4 and O2-N2 separation was obtained through benzene cracking on ACS with benzene entrantment of 0.40×10-4 g/ml at cracking temperature of 725℃ for a period of 90 minutes resulting in a selectivity of 3.31:1.00 for O2-N2 and 8.00:1.00 for CO2-CH4 pair of gases respectively.

Oxidation characteristics of benzene as a VOC was investigated using a fixed bed reactor system over copper base catalysts. The copper base catalysts were made by using copper nitrate reagent and various support materials such as γ-Al2O3, TiO2, and zeolite. The parametric tests were conducted at the reaction temperature range of 200～500℃, benzene concentration of 1,000～2,000 ppm, and space velocity range of 5,000～20,000 hr-1. The property analyses such as BET, SEM, XRD and the conversions of catalytic oxidation of VOC were examined. XRD analysis on copper catalysts showed CuO crystal forms and the peak intensity of CuO increased as the impregnation weight of copper grew. The experimental results showed that the conversion was increased with decreasing space velocity. It was also found that Cu/γ-Al2O3+TiO2 catalyst showed the highest activity for the oxidation of benzene and 15% metal loading was the optimum impregnation level.

This study was conducted to evaluate the biofiltration treatment characteristic for benzene vapor gas. Compost and calcium silicate porous material were used as biofilter fillers. Gas velocity and empty bed retention time were 15 m/hr and 4 min, respectively. Benzene gas removal efficiency of P-Bio (calcium silicate porous material with inoculation) was the highest and maintained in over 98%. After shock input of benzene gas, the removal efficiency of P-Bio biofilter was recovered within 2 days, while 5 days were taken in CP-Bio (compost + calcium silicate porous material mixture with inoculation) and CP (compost + calcium silicate porous material mixture without inoculation) biofilters. The removal efficiency of P-Bio biofilter was near 100% in the loading rate of 〈85g/m3(filling material)/hr, It was shown that the maximum elimination capacities of P-Bio, CP-Bio, and CP biofilters were 95, 69, and 66 g/m3(filling material)/hr, respectively. Microbial number of P-Bio, which the number was the lowest at start-up, was 3 orders increased on operational day 48. CO2 was generated greatly in order of P-Bio, CP-Bio, and CP biofilters.