Abstract: In the present study, feasibility of the selective surface
hydrophilization of polyvinyl chloride (PVC) by microwave treatment
was evaluated to facilitate the separation from automotive shredder
residue (ASR), by the froth flotation. The combination of 60 sec
microwave treatment with PAC, a sharp and significant decrease about
16.5° contact angle of PVC was observed in ASR plastic compared
with other plastics. The microwave treatment with the addition of PAC
resulted in a synergetic effect for the froth flotation, which may be a
result of the 90% selective separation of PVC from ASR plastics, with
82% purity. While, simple mixing with a nanometallic Ca/CaO/PO4
dispersion mixture immobilized 95-100% of heavy metals in ASR
soil/residues. The quantity of heavy metals leached from thermal
residues after treatment by nanometallic Ca/CaO/PO4 was lower than
the Korean standard regulatory limit for hazardous waste landfills.
Microwave treatment can be a simple and effective method for PVC
separation from ASR plastics.
Abstract: A double module hollow fiber supported liquid
membrane (HFSLM) was applied to selectively separate lead and
mercury ions from dilute synthetic produced water. The experiments
were investigated on several variables: types of extractants
(D2EHPA, Cyanex 471, Aliquat 336, and TOA), concentration of the
selected extractant and operating time. The results clearly showed
that the double module HFSLM could selectively separate Pb(II) and
Hg(II) in feed solution at a very low concentration to less than the
regulatory discharge limit of 0.2 and 0.005 mg/L issued by the
Ministry of Industry and the Ministry of Natural Resource
Environment, Thailand. The highest extractions of lead and mercury
ions from synthetic produced water were 96% and 100% using 0.03
M D2EHPA and 0.06 M Aliquat 336 as the extractant for the first
and second modules.