Ball Mill-Assisted Dechlorination of Flexible and Rigid Poly(vinyl chloride) in NaOH/EG Solution

Abstract

Both flexible and rigid forms of poly(vinyl chloride) (PVC) were effectively dechlorinated in NaOH/ethylene glycol (EG) solution during ball mill pulverization. The high degree of dechlorination obtained was attributed to the increased surface area of the crushed PVC particles and the resulting enhancement of contact between the PVC and dissolved hydroxide ions. The common additives diisononyl phthalate and CaCO3 were easily separated from the PVC bulk during the dechlorination reaction. The reaction proceeded under chemical control, with degrees of dechlorination for both flexible and rigid PVC increasing with temperature with apparent activation energies of 110 and 80 kJ/mol, respectively. This reaction was accurately represented by a modified shrinking-core model.

Beyond Mechanical Recycling: Giving New Life to Plastic Waste

“…[89] Thep rocess can also be run in wet and basic conditions. [90] As another pre-treatment for pyrolysis,asteamexplosion treatment has been shown to lower the liquefaction temperature by 50 8 8Cf or PS and by 100 8 8Cf or HDPE. [91] 2.1.2.…”

Base-catalysed, one-step mechanochemical conversion of chitin and shrimp shells into low molecular weight chitosan

“…Recently, mechanochemistry has been widely applied in chemical and material synthesis with the unique advantage of enabling efficient solid-state reactions and the ability to directly convert various recalcitrant feedstocks. [61][62][63][64][65][66][67][68][69][70][71][72][73][74] A series of studies transforming biomass in a solvent-free way have been demonstrated. For example, cellulose was converted to watersoluble oligomers by both mineral acids and solid acids in a ball milling process, 75,76 while lignin was decomposed similarly in the presence of a base.…”

Chemically Modified Polyvinyl Chloride for Removal of Thionine Dye (Lauth’s Violet)

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