Dechlorination of polyvinyl chloride electric wires by hydrothermal treatment using K2CO3 in subcritical water

Hydrothermal pretreatment of biomass can improve fuel characteristics based on the decomposition properties of subcritical water. Thus, this study used a hydrothermal treatment to improve the fuel characteristics of empty fruit bunches (EFBs), which are generated as waste after palm oil extraction. The experimental reaction temperature was increased from 180 °C to 250 °C at an interval of 10 °C and the mass ratios between the dry sample and water content were set to 1:8 and 1:16 so that the sample was sufficiently immersed. Additionally, the material properties of EFB under hydrothermal treatment conditions were investigated using mass and energy yields, elemental analysis, proximate analysis, thermogravimetric analysis, derivative thermogravimetry, and Fourier transform infrared spectroscopy analysis of the reaction products. As the reaction temperature increased, the fixed carbon content and heating value increased because volatile matter, including oxygen, was removed first, which is similar characteristics to coal. All analyses revealed that the water content exhibited little influence on EFB material properties since the samples were sufficiently immersed in water. Thus, it is not necessary to add more water that required for sample immersion for the hydrothermal treatment of EFB.

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Application of Subcritical Water to Dechlorinate Polyvinyl Chloride Electric Wires

10.20944/preprints201809.0384.v1 ◽

2018 ◽

Author(s):

Aurora Soler ◽

Juan A. Conesa ◽

Nuria Ortuño

Keyword(s):

High Pressure ◽

Polyvinyl Chloride ◽

Aromatic Hydrocarbons ◽

Subcritical Water ◽

Heating Rates ◽

Chlorinated Pollutants ◽

Different Temperatures ◽

Polycyclic Aromatic ◽

Laboratory Scale Reactor ◽

Scale Reactor

Polyvinyl chloride (PVC) electric wires were subjected to dechlorination in subcritical water at three different temperatures in a high-pressure reactor. About 2.09, 73.08 and 95.96 wt. % of chlorine in PVC wires was removed during dechlorination at 200, 250 and 300 °C, respectively. The solid residues were analyzed and characterized by thermogravimetry, at three different heating rates (5, 10 and 20 °C/min) in inert and oxidizing atmosphere. With the purpose of studying the emission of chlorinated pollutants, pyrolysis experiments at 850 °C were also performed in a laboratory scale reactor with the dechlorinated materials, as well as with the original PVC electric wire. Polycyclic aromatic hydrocarbons (PAH) formation increased, but chlorobenzenes (ClBz) and chlorophenols (ClPh) formation decreased as the temperature of dechlorination increased; naphthalene was the most abundant PAH and monochlorobenzene and monochlorinated phenols (3-+4-) were the most abundant chlorinated compounds.

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Dechlorination of polyvinyl chloride by hydrothermal treatment with cupric ion

Process Safety and Environmental Protection ◽

10.1016/j.psep.2020.08.040 ◽

2021 ◽

Vol 146 ◽

pp. 108-117 ◽

Cited By ~ 1

Author(s):

Dachao Ma ◽

Liwu Liang ◽

Erfeng Hu ◽

Huaquan Chen ◽

Dongbo Wang ◽

...

Keyword(s):

Hydrothermal Treatment ◽

Polyvinyl Chloride ◽

Cupric Ion

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Solid Biofuel Production from Meranti (Shorea Sp.) Sawdust Using Hydrothermal Treatment

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.789.104 ◽

2018 ◽

Vol 789 ◽

pp. 104-109

Author(s):

Indah Astieningsih Mappapa ◽

Ahmad T. Yuliansyah

Keyword(s):

Hydrothermal Treatment ◽

Subcritical Water ◽

Raw Materials ◽

Initial Pressure ◽

Biofuel Production ◽

Effect Of Temperature ◽

Waste Biomass ◽

Wood Processing ◽

Solid Biofuel ◽

Proximate And Ultimate Analysis

In the context of industrialization, wood industry plays an important role as one of thepillar components in building Indonesia industry where 76.36% is supported by Meranti (Shorea Sp.).However, the increase of wood processing industries produces waste biomass in the form of largeamount sawdust. Hydrothermal treatment is an environmentally clean technology of convertingbiomass into coal-like solid called hydrochar using subcritical water. The purpose of this research isto determine the effect of temperature and water to biomass (b/w) ratio in the formation of hydrocharfrom Meranti sawdust. This research was carried out using a 250 mL hydrothermal reactor where amixture of Meranti sawdust and water heated at temperature variation of 240 and 300oC; b/w ratio1:20, 2:20, 3:20; initial pressure of 1.0 Mpa and holding time for 30 minutes. Hydrochar were thencharacterized in terms of yield, caloric value, proximate and ultimate analysis. Based on experimentalresult, 39-78% raw materials were converted into hydrochar where the highest yield was found ontemperature operation of 240oC and b/w ratio 2:20.

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