Upcycling of PVC waste to high-value sorbent with KOH-activation for efficient removal of organic dyes

Youngwoo Kwak; Junhyeok Eom; Hyungseok Nam; Changwoo Nam

doi:10.1016/j.chemosphere.2024.142283

Upcycling of PVC waste to high-value sorbent with KOH-activation for efficient removal of organic dyes

Chemosphere. 2024 May 9:359:142283. doi: 10.1016/j.chemosphere.2024.142283. Online ahead of print.

Authors

Youngwoo Kwak¹, Junhyeok Eom¹, Hyungseok Nam², Changwoo Nam³

Affiliations

¹ Carbon Composites Convergence Materials Engineering, Jeonbuk National University, 567 Baekje-daero, Deokjin-dong, Deokjin-gu, Jeonju, Jeollabuk-do, 54896, Republic of Korea.
² School of Mechanical Engineering, Kyungpook National University, Daegu, 41950, Republic of Korea.
³ Carbon Composites Convergence Materials Engineering, Jeonbuk National University, 567 Baekje-daero, Deokjin-dong, Deokjin-gu, Jeonju, Jeollabuk-do, 54896, Republic of Korea. Electronic address: cun120@jbnu.ac.kr.

PMID: 38734251
DOI: 10.1016/j.chemosphere.2024.142283

Abstract

Polyvinyl chloride (PVC), known for its chemical stability and flame-retardant qualities, has many uses in various fields, such as pipes, electric wires, and cable insulation. Research has established its potential recovery as a fluidic fuel through pyrolysis, but the use of PVC pyrolysis oil, which is tainted by chlorine, is constrained by its low heat value and harmful environmental effects. This study engineered a layered double hydroxide (LDH) to tackle these challenges. The LDH facilitated dechlorination during PVC pyrolysis and bolstered thermal stability via cross-linking. During pyrolysis with LDH, PVC was transformed into carbon-rich precursors to sorbents. Chemical activation of these residues using KOH created sorbents with a specific surface area of 1495.4 m² g⁻¹, rendering them hydrophilic. These resulting sorbents displayed impressive adsorption capabilities, removing up to 486.79 mg g⁻¹ of methylene blue and exhibiting the simultaneous removal of cations and anions.

Keywords: Activation; Dye adsorption; Layered double hydroxide; Polyvinyl chloride; Pyrolysis.