De-agglomeration and homogenisation of nanoparticles in coal tar pitch-based carbon materials

Abstract

The aim of the work was to characterise coal tar pitch (CTP) modified with selected nanoparticles as a binder precursor for the manufacture of synthetic carbon materials. Different factors influencing the preliminary preparative steps in the preparation of homogenous nanoparticle/CTP composition were studied. Graphene flakes, carbon black and nano-sized silicon carbide were used to modify CTP. Prior to introducing them into liquid CTP, nanoparticles were subjected to sonication. Various dispersants were used to prepare the suspensions, i.e. water, ethanol, dimethylformamide (DMF) and N-methylpyrrolidone (NMP).The results showed that proper dispersant selection is one of the most important factors influencing the de-agglomeration process of nanoparticles. DMF and NMP were found to be effective dispersants for the preparation of homogenous nanoparticle-containing suspensions. The presence of SiC and carbon black nanoparticles in the liquid pitch during heat treatment up to 2000 °C leads to the inhibition of crystallite growth in carbon residue.

Study of the Carbonization and Graphitization of Coal Tar Pitch Modified with SiC Nanoparticles

“…Finally, the compositions were heated to 165 ∘ C to transform CTP into liquid state and mechanically stirred for 15 minutes. The detailed procedure of nSiC deagglomeration and homogenization with CTP is described elsewhere [21]. According to this procedure, CTP samples containing different amounts of nSiC from 2% to 10% were prepared.…”

Optimization of Selected Charcoal Powder Composite Electrode for Electrochemical Treatment of Landfill Leachate

“…Stirrers were used throughout to maintain homogeneity of the sample. Results and Discussion Study on the surface morphology of the five charcoal powders VPSEM was used to examine the appearance of the charcoal powder obtained from five types of charcoal (Figures 2). Results of the VPSEM analysis show that charcoal powder particles are irregularly shaped, with different sizes [19]. Mangrove charcoal appears to have a smooth surface and a few holes.…”

Ultrasonication optimisation and microstructural characterisation for 3D nanoparticle dispersion in thermoplastic and thermosetting polymers

“…Therefore, the matrix-particle cavitation bubbles, subsequently disrupting physical or chemical interactions between the suspended primary particles. A multitude of parameters determines the breaking efficiency of both aggregates and agglomerates, such as the used ultrasonication power, time, and frequency, the ultrasonicator type, suspension type, volume, particle concentration, viscosity, vapour pressure and temperature [17][18][19][21][22][31][32][33][34][35][36][37][38].…”

“…𝐸 " 12 ) [31,36]. Nevertheless, large powers or times have resulted in possible re-agglomeration; hence, the optimisation and general trends of a developed ultrasonication procedure remain a system-specific challenge [18][19]22,38]. As an illustrative example, sonotrode-type ultrasonication has proven to break up (nano)particles efficiently, whereas bath-type ultrasonication is preffered to delaminate and disperse 1D rod-like and 2D sheet-like nanoparticles, such as CNTs and MXenes [32,[37][38].…”