Petrochemical Wastewater Treatment by Eggshell Modified Biochar as Adsorbent: Atechno-Economic and Sustainable Approach

Abstract

Petrochemical industrial wastewater (PIW)contains toluene and xylene (TX), and various organic and inorganic pollutants, causing severe risks to human health if improperly released into the environmental matrices. For the long-term reliability of environmental conservation, this study illustrates the interlinkage between PIW treatment and the three pillars of sustainable development. Sewage sludge biochar was modified with eggshell, showing a relatively high fixed C content (increase in carbonization degree), and small O/C and N/C ratios. The prepared biochar was employed for TX adsorption in mono-component solutions, giving removal efficiencies of 79.1% (T) and 86.6% (X), at pH =10, adsorbent dosage =2 g/L, and Co =40 mg/L within 60 min. The main adsorption mechanism was physisorption, including precipitation/pore-filling, π-π dispersive interaction, and van der Waals force. The modified biochar also treated real PIW under five adsorption/regeneration cycles, providing essential steps toward large-scale applications. According to an economic feasibility estimation, the biochar application for treating 1 m3 of PIW would offer a payback period of 6.9 yr. The study outputs could be linked to the restoration of water-related ecosystems, biochar modification for industrial applications, and climate change mitigation, adopting the 2030 agenda and its sustainable development goals (SDGs).

The Improvement of Natural Thai Bentonite Modified with Cationic Surfactants on Hexavalent Chromium Adsorption from an Aqueous Solution

“…Both MTBs presented similar adsorption patterns and efficacies. Rapid Cr(VI) adsorption can imply the combination of physical and chemical adsorptions on the adsorption progress, especially for physical adsorption during rapid adsorption progress [19, 37] and the accessibility of large amounts of vacant active sites [39]. Additionally, the inability of adsorbents to remove Cr(VI) at the later stages can indicate the limitation of active sites and slow diffusion of Cr(VI) ions to the interior of the bentonite surface which became full as time progressed [8, 31].…”

Fourth Industrial Revolution of Wastewater Treatment with Adsorption

“…Kumi et al [13] represented the application of the pyrolysis process to convert sewage sludge into biochar. The biochar elemental composition was modified by adding eggshell waste, generating an adsorbent suitable for toluene and xylene (TX) removals.…”

Transition towards Sustainable Carwash Wastewater Management: Trends and Enabling Technologies at Global Scale

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