Steel slag as low-cost adsorbent for the removal of phenanthrene and naphthalene

Abstract

This study investigates the removal effectiveness and characteristics of phenanthrene and naphthalene using low-cost steel slag with batch experiments. The adsorption characteristics of steel slag were measured and analysed using X-ray fluorescence, X-ray diffraction, and Fourier transform infrared spectroscopy. The batch experiments investigated the effect of the time gradient, pH, and steel slag dosage gradient on the adsorption of the steel slag. The results show that with time and dosage of steel slag increased, the adsorption capacity of phenanthrene and naphthalene increased and gradually became balanced, but pH had no obvious effect on the adsorption of phenanthrene and naphthalene. The Langmuir isotherm model best describes the phenanthrene and naphthalene removal by the steel slag, which shows the adsorption occurring in a monolayer. The maximum adsorption capacity of the steel slag to phenanthrene and naphthalene is 0.043 and 0.041 mg/g, respectively. A pseudo-first-order kinetic model can better represent the adsorption of phenanthrene and naphthalene by steel slag. The research demonstrates that the steel slag has a certain adsorption capacity for phenanthrene and naphthalene.

Ironmaking and Steelmaking Slags as Sustainable Adsorbents for Industrial Effluents and Wastewater Treatment: A Critical Review of Properties, Performance, Challenges and Opportunities

“…The findings indicate that an increase in the amount of crystalline phases such as gehlenite (Ca 2 Al 2 SiO 7 ), larnite (Ca 2 SiO 4 ), bredigite (Ca 5 MgSi 3 O 12 ), merwinite (Ca 3 Mg(SiO 4 ) 2 ) and akermanite (Ca 2 MgSiO 7 ), among others, significantly increases the adsorption capacity of cations and anions from solution [15,19,25,57,58]. However, since these phases may not always be uniformly present in the post-solidification state, several studies have explored in detail the impact of activation and modification on the adsorption capacities of slags [42,57,[59][60][61][62][63][64][65][66]. Section 5 further discusses in detail the common modification and activation techniques and their impacts on the performance of slags.…”

“…To date, several studies have reported on the benefits of modification and/or activation treatment to increase the specific surface area and density of adsorption sites on the surfaces of the adsorbent particles [42,57,[59][60][61][62][63][64][65][66]. Other studies have also proposed the synthesis of functionalised adsorbents such as geopolymers [74,[118][119][120][121][122][123], permeable reactive barriers or slag filters [124][125][126][127][128][129][130][131][132], zeolites and zeolite precursors [133][134][135] and layered double-hydroxide-based adsorbents [133][134][135][136][137][138].…”

“…Thermal activation involves purposeful heat treatment, with and without additives, to increase the amount of crystalline phases in solidified slags. To date, extensive studies have highlighted the benefits of activation of slags for use in the adsorption of cations and anions from industrial effluents and wastewaters [42,57,[59][60][61][62][63][64][65][66]139,140]. In particular, Yang et al [139] investigated the effect of nitrate removal by thermally activated steelmaking slags mixed with Al(OH) 3 .…”

Reduction of Chemical Oxygen Demand (COD) Effluent of Plastic Recycling Processing Plant using LD Slag

“…Study done by [11] showed that the LD slag as a wetland substrate was feasible to decrease COD. The removal of COD from wastewater by LD slag is mainly based on the oxide minerals released from the LD slag which it can adsorb and precipitate organic matter [12].…”

“…Activated carbon can be manufactured from carbonaceous material such as coal, peat, wood or nutshells. Most adsorption process using activated carbon can reduce more than 70% of COD in the treatment of wastewater [12]. LD slag contains various amounts of metals and chemical components that can be helpful for various applications and treatment [16][17][18][19].…”