Effects of Temperature and Relative Humidity on Benzene Adsorption by Porous Activated Carbons from Lignocellulosic Biomass: Experimental Insights

Investigating the contamination of indoor air with benzene is a global issue because it causes harm to humans. Gas adsorption has been applied for benzene removal from a gaseous environment, potentially threatening human health. Activated carbon (AC) has recently gained the interest of influential purification industries because of its significantly high adsorption capacity against air pollutants like benzene. A low-cost chemically-ACs (AGCACs) from lignocellulosic biomass was produced by pyrolysis (600-900 oC) of the precursor impregnated with H3PO4 activating agents (1:1, 3:1, 5:1). 5:1 H3PO4 activated carbon (AGCAC800-5) featured a high specific surface area (703 m2/g) and a large pore volume (0.547 cm3/g). Scanning electron microscope (SEM) analysis confirmed that the AGCAC800-5 exhibited enhanced total basicity. The AGCAC800-5 showed superior benzene uptakes of 105 and 92 mg/g at room temperature (22±0.3 oC) under humid conditions (40±2 and 60±2% relative humidity). It was emerging gas-solid interaction mechanisms for benzene capture with AGCACs by demonstrating high capacities correlated with high surface areas. The finding reveals that Agrostis capillaris residual biomass is a useful material for producing adsorbents, and successful testing outcomes demonstrate that AGCAC800-5 exhibited great potential to adsorb benzene vapor. Transformation of lignocellulosic biomass into AC can solve environmental issues such as agricultural residues and air pollution management, which could be regarded as a fine sorbent.