Microscopic studies on the polymers decomposition in a closed volume at elevated temperatures in the presence of bulk NiCr alloy

Abstract

In the present work, self-disintegration of the bulk metallic Ni-Cr alloy in the presence of different polymer compounds under the conditions of closed volume and elevated temperatures is studied. It was found that in the cases of polymers containing in addition to carbon only hydrogen atoms (polyethylene) or only halogen atoms (polytetrafluoroethylene), self-disintegration does not proceed noticeably even at temperatures as high as 800 °C. The predominating form of the solid product is non-catalytic carbon shaped as microspheres or their sintered agglomerates. On the contrary, for decomposition of the polymer containing hydrogen and halogen atoms (polyvinylchloride), self-dispersion of the bulk alloy is significantly facilitated. This process is accompanied with formation of catalytically derived forms of structured carbon within all the studied temperature range (500-800 °C). The most common form of the carbon deposits is nanofibers. At the same time, some unusual carbon structures were observed, among which the solid-phase carbon-nickel microcrystals of a regular cubic shape with pyramidal cavities on each facet are of special interest. The studied process can be considered as an alternative approach for utilization and recycling of the plastic wastes.

Comparative Study on Carbon Erosion of Nickel Alloys in the Presence of Organic Compounds under Various Reaction Conditions

“…As reported by Gedanken et al [35][36][37][38][39][40], the RAPET conditions give a unique possibility to obtain new classes of structurally organized materials. A similar approach was applied in our recent works to study catalytic pyrolysis in the presence of bulk nickel alloys [32][33][34]45]. The proposed characterization method is based on the registration of the FMR spectra in an in situ mode.…”

Efficient Photocatalytic H2O2 Production Ability of a Novel Graphitic Carbon Nitride/Carbon Composites under Visible Light

“…[16][17][18] Since the main components of Microplastics (MPs) are polymers, they can be used as a carbon source for synthetic carbon materials. [19] Therefore, exploring the economical and green way to utilize microplastics is also meaningful work. Min et al [20] prepared 3D porous carbon with excellent performance in lithiumion batteries.…”

Elimination of Composition Segregation in 33Al–45Cu–22Fe (at.%) Powder by Two-Stage High-Energy Mechanical Alloying

“…Most studies on Al–Cu–Fe alloys were aimed at the synthesis of Al 63-70 Cu 20-25 Fe 10-12 quasicrystals of icosahedral structure [ 3 , 4 , 5 , 6 , 7 ] for a variety of applications: antimicrobial agents [ 8 ], decomposition of hazardous materials [ 9 ], carbon nanotube growth catalysts [ 10 ], magnetic materials [ 4 , 11 ], anodes in lithium batteries [ 12 ], fillers with ultralow wear [ 13 ], and catalysts in steam reforming of methanol [ 14 , 15 ]. Moreover, nanostructured powder alloys are becoming popular in traditional heterogeneous catalysis [ 16 , 17 ], e.g., in hydrogenation reactions of CO (CO 2 ) [ 18 ], synthesis of carbon fibers [ 19 ], decomposition of chlorine-containing hydrocarbons [ 20 , 21 ], decomposition of polymers [ 22 ], and in steam and dry reforming [ 23 ].…”