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The activated carbons developed using Phaseolus vulgarisL. (PVACs) were produced to enhance the benzene, toluene, ethylbenzene, and xylene (BTEX) adsorption. The PVACs chemically produced via phosphoric acid (H3PO4) from biomass waste and effectively found the adsorption capacity for multi-component BTEX. In accordance with the experiment protocols, a set of systematic operating parameters (temperature, residence time, and initial BTEX concentration) carried out to investigate the mechanism of multi-component BTEX adsorption on the PVACs (PVAC650, PVAC750, and PVAC850 named as carbonization temperature from 650 to 850 °C). The ambient temperature was kept constant at 22 °C, and the differences of BTEX adsorbed amount were clearly demonstrated in the experiments. The results indicate that (1) specific surface area is important for novel application in multi-component BTEX adsorption, and the surface area of PVAC650, PVAC750, and PVAC850 were 881, 1109, and 1007 mg/g; and (2) temperature and relative humidity have an important effect on the absolute BTEX adsorption, which BTEX adsorbed amount decreases at higher temperature and relative humidity. Under the condition of 15% relative humidity (RH), the maximum BTEX adsorption amounts for PVAC650, PVAC750, and PVAC850 were 189, 281, 217 mg/g at, respectively. The average multi-component of BTEX adsorption on PVAC750 is 235 mg/g, indicating that the dominant adsorption process of BTEX at room conditions may be physical adsorption.

The poor indoor air quality can be associated with the released volatile organic compounds (VOCs) from different sources. The extent of the concern may increase depending on the presence of benzene, toluene, ethylbenzene, and xylene (BTEX) and exposure to them in the indoor air. Adsorption with activated carbon, which is a very effective method, is preferred to eliminate highly volatile gaseous pollutants and reduce the extend of their negative impact. In this work, the removal efficiency of a novel activated carbons (MSRACs), prepared from stems of Corylus colurna(CCBW) by chemical processes using H2SO4, H3PO4, and HCl, was scrutinized towards BTEX pollutants. The adsorbents acquired from this lignin-based waste were investigated from porosity and surface chemistry aspects. The highest surface area of 1424 m2/g and micropore volume of 0.46 cm3/g were attained after activation of MSRAC11 adsorbent sample by H2SO4-70wt%. The performances of the fabricated adsorbent samples were evaluated and the order of MSRAC11>MSRAC24>MSRAC36 was obtained in the multiple concentrations of BTEX. This study introduces an easy method for producing efficient adsorbents from lignin-based waste for filtering indoor air and designing BTEX-capturing systems for various applications.

The innovative and sustainable adsorption technologies for gas phase naphthalene (GPNAP) have attracted attention as a successful method. To remove polycyclic aromatic hydrocarbons effectively, biomass-based activated carbon was produced by chemical activation. The adsorption behavior of naphthalene onto produced activated carbon was also investigated by the BET-specific surface areas, total pore volumes, and average pore sizes. The resulting DCAC800 has successfully prepared a very high surface area (607.5 m2/g) by the weight ratio of 1:3 as the H2SO4activation agent and the pyrolysis of the resultant material at 800 °C under an N2atmosphere. It has been determined that when the humidity in the environment is increased from 30 to 90% RH, it causes a loss of efficiency between 64–71% for DCAC500, DCAC600 DCAC700 DCAC800, and DCAC900. The adsorption experiments at 30% RH showed that the DCAC800 had a strong adsorption affinity to naphthalene and the maximum adsorption amount was shown to reach up to 296 mg/g in a fixed-bed reactor.