Synthesis of nZVI-BC composite for persulfate activation to degrade pyrene: Performance, correlative mechanisms and degradation pathways

Biochar loaded with cobalt ferrate activated persulfate to degrade naphthalene

“…However, under alkaline conditions, SO 4 − ˙ will be consumed (eqn (3)), resulting in reduced degradation of pollutants. 65 Although OH˙ has oxidation capacity, SO 4 − ˙ has a higher REDOX potential (2.5–3.1 V) and a longer half-life (30–40 μs) 27 than OH˙ (1.8–2.7 V). 28 Similar to the results of published literature, 62 the degradation of atrazine by the nano-zero-valent iron-persulfate system at different pH conditions was also in this trend.S 2 O 8 2− + H + → HS 2 O 8 − → SO 4 2− + SO 4 − ˙+ H + SO 4 − ˙ + OH − → SO 4 2− + OH˙…”

“…66,67 They can lead to the conversion of powerful SO 4 − ˙ and OH˙ into less reactive chlorine and carbonate radicals (eqn (4)–(8)). 42,68 The OH˙ in the system can be converted from SO 4 − ˙ (eqn (4) 65 ).SO 4 − ˙ + H 2 O → OH˙ + SO 4 2− + H + Cl − + SO 4 − ˙ → SO 4 2− + Cl˙Cl − + OH˙ → Cl˙ + OH − HCO 3 − + SO 4 − ˙ → CO 3 − ˙ + SO 4 2− + H + HCO 3 − + OH˙ → CO 3 − ˙ + H 2 O…”

“…Therefore, C1, C4, C6 and C9 are easier to be attacked by SO 4 − ˙ and OH˙ and take the lead in reaction. Studies 65,91 have shown that aromatics mainly undergo hydroxylation, ring opening and decarboxylation in oxidation systems. Combined with the above conclusions, the possible degradation pathways of naphthalene were expounded, as shown in Fig.…”

A review of recent studies on nano zero-valent iron activated persulfate advanced oxidation technology for the degradation of organic pollutants

“…Pyrene is a polycyclic aromatic hydrocarbon compound that is highly toxic and carcinogenic, posing significant risks to human health and the environment. Junyuan Guo et al 67 utilized nZVI-BC in a persulfate activation system for the degradation of pyrene. The experimental results demonstrate that the nZVI-BC composite material, under the action of persulfate, can generate a large amount of hydroxyl radicals and sulfate radicals, triggering the oxidation reaction of pyrene and transforming it into harmless substances such as short-chain aromatic hydrocarbons and fatty acids.…”

Wheat straw biochar and its performance in treatment of phenanthrene containing water and microbial remediation of phenanthrene contaminated soil

“…With the acceleration of industrialization and social and economic development, environmental pollution has become increasingly serious. In particular, a massive amount of polycyclic aromatic hydrocarbons (PAHs) generated from vehicle exhaust emissions, gas and coal tar production, wood processing, and oil spills were released into soil and water bodies, posing a major threat to the ecological environment and human health (Zhang et al, 2021;Guo et al, 2022). Today, PAHs are highly persistent in water and soil bodies and are difficult to handle due to their inherent properties such as low volatility and poor water solubility (Piscitelli et al, 2019).…”