Separation of Carbon from Deinking Waste by Means of Flotation

The technique of froth flotation, as practiced in the separation of mineral ores, has been applied to the separation of carbon black from the deinking waste of the paper industry. On the theory that carbon black (from ink) has a positive charge in water, and clay and cellulose fibers have negative charges in water, experiments were of two types. First, it was attempted to float the carbon from the clay and cellulose fibers. Second, it was attempted to float the clay and cellulose fibers from the carbon. Several possible formulas were found for separating carbon black from deinking waste. Favorable results were obtained in both types of experiments

Theoretical and experimental aspects of carbon formation in thermal plasma

Formation of carbon black from Freons was studied in RF thermal plasma conditions. Equilibrium compositions of the products were calculated by computer code ASTRA 4.0. The experiments on thermal decomposition were performed in an RF thermal plasma reactor. By comparing the calculated and experimental results a model was constructed on carbon black formation in RF thermal plasma reactor

Laser ignition of an optically sensitised secondary explosive by a diode laser

As a green technology, laser ignition of a relatively insensitive secondary explosive has been experimentally investigated. The explosive, hexanitrostilbene (HNS), was doped with one of two optical sensitizers, carbon black or a laser absorbing dye, and a continuous-wave (CW) infrared diode laser was used as the igniting source. The ignition sensitivities of HNS with each of the two optical sensitizers were analysed and compared in terms of: optical power threshold for ignition, ignition delay and full burn delay at various laser powers. The results have shown that both the chemical dye and carbon black optically sensitize the explosive with similar efficiencies. In contrast to the carbon black, the dye provides wavelength specificity and selectivity in the laser ignition process and its solubility in some specific solvents improves the coating of the explosive material. It was therefore concluded that the laser absorbing dye is a better candidate for optical sensitization in laser ignition than the commonly used carbon black. The combination of laser ignition sensitivity with wavelength selectivity potentially offers higher reliability and safety at a low optical power for future ignitors of secondary explosives

Effective conductivity in association with model structure and spatial inhomogeneity of polymer/carbon black composites

The relationship between effective conductivity and cell structure of polyethylene/carbon composites as well as between effective conductivity and spatial distribution of carbon black are discussed. Following Yoshida's model both structures can, in a way, be said to be intermediate between the well known Maxwell-Garnett (MG) and Bruggeman (BR) limiting structures. Using TEM photographs on composites with various carbon blacks we have observed that the larger is Garncarek's inhomogeneity measure H of two-dimensional (2D) representative distribution of the carbon black, the smaller is the effective conductivity of the composite.Comment: 7 pages, 9 figure

Modeling carbon black reinforcement in rubber compounds

One of the advocated reinforcement mechanisms is the formation by the filler of a network interpenetrating the polymer network. The deformation and reformation of the filler network allows the explanation of low strain dynamic physical properties of the composite. The present model relies on a statistical study of a collection of elementary mechanical systems, This leads to a mathematical approach of the complex modulus G* = G' + iG". The storage and loss modulus (G' and G", respectively), are expressed in the form of two integrals capable of modeling their Variation with respect to strain

Effect of Vulcanization System and Carbon Black on Mechanical and Swelling Properties of EPDM Blends

EPDM (Ethylene propylene diene monomer) is one of synthetic rubber that widely used in automotive. It must be vulcanized and added by other materials before used. The aim of this study is to investigate the effect of vulcanization system and the addition of carbon black (CB) to the mechanical properties and swelling characteristic of EPDM. This research used three vulcanization system, conventional vulcanization (CV), efficient vulcanization (EV) and semi-efficient vulcanization (SEV) with the variation of carbon black 50, 60, 70 phr (per hundred resin). This research showed that EV system resulted faster vulcanization time and lower delta torque than SEV and CV systems. This system also performed the highest tensile strength, elongation, and tear strength, while SEV system resulted the highest hardness. Furthermore, the conventional vulcanization system resulted the lowest swelling index

Penelitian Pengaruh Campuran Carbon Black Dan China Clay Terhadap Sifat Tegangan Putus Dan Kekerasan Karet Vulkanisat

It has been done a research of the influence of mixed carbon black and hardness properties on the vulcanization of rubber. It has been made with additive of carbon black and China clay mixed, in total variation. The result is seen that total variation of carbon black and China clay not influence to tensile strength, but their interacton can do it. The hardness of vulcanization of rubber will be influence by total variation of carbon black China clay anad their interaction. INTISARI Telah dilakukan penelitian pengaruh campuran carbon black dan China clay terhadap sifat tegangan putus dan kekerasan kompon karet. Trelah dibuat kompon karet cetak vulkanisasi dengan memvariasikan jumlah campuran carbon black dan China clay. Hasil penelitian menunjukkan bahwa variasi jumlah China clay tidak mempengaruhi nilai tegangan putus, tetapi interaksinya dapat berpengaruh sangat nyata. Kekerasan kompon karet vulkanisasi sangat dipengartuhi oleh variasi jumlah carbon black dan China clay serta interaksinya

Indentation toughness of Al2O3-CNT nanocomposites

In the last few years new ceramic/carbon nanotube composites have been developed and a number of authors have reported improved mechanical and functional properties in the case of ceramic/CNT composites compared to the monolithic materials. according to the results reinforcing by CNTs in many cases improved the fracture toughness of Al2O3, however, this toughening is not evident, and some of the variations may purely arise from using different testing techniques. The improvement in fracture toughness is due to bridging of the crack surfaces by CNTs during the crack propagation by CNT pullout mechanism, which strongly depends on the interfacial bonding between CNTs and the matrix. The aim of the present work is to investigate the effect of addition of carbon nanotubes and carbon black on the indentation toughness of alumina-CNT and alumina-carbon black nanocomposites

Carbon black mediated conductive polymer composite

The central goal of this thesis is to produce electrically conductive nanocomposites made out of carbon black obtained from waste tires as filler into a polymeric matrix. Waste tires are discarded in substantial numbers on a daily basis, posing a significant environmental concern. By weight, about 25-35% of a tire is carbon black. Pyrolysis is a convenient and environmentally friendly process to produce carbon black from tires. Due to carbon black’s low density, high electrical conductivity and economical feasibility, this thesis investigates the electrical conductivity of nanocomposites that utilizes carbon black particles as fillers. As a result of its modified and controllable properties, composites with fillers present a radical alternative to conventional polymers and their blends. The small size of the fillers leads to exceptionally large interfacial area in the composites. The interface controls the degree of the interaction between the filler and the polymer thus controlling the properties. The effect of annealing temperature (550°C-1250°C) on the electrical properties of carbon black obtained from tires was investigated. Generally, the DC electrical conductivity improved when the annealing temperature increased. The modulation of the electrical conductivity as a function of annealing temperatures was explored using Raman spectroscopy, Energy dispersive X-ray, Scanning electron microscopy, X-Ray diffraction and thermo-gravimetric analysis. Annealed carbon black was used as filler in a polymeric matrix. The annealed waste carbon black was blended into epoxy at different wt. % to investigate the electrical conductivity. Furthermore, annealed carbon black was used as filler in a Carbon Fiber Reinforced vii Polymer (CFRP) and then the effect of different percentage of waste carbon black was studied. After that, through plane electrical conductivity, surface electrical conductivity, through plane thermal conductivity and flexural strength were examined. The results showed that the electrical conductivity for the annealed carbon black at 1250°C was improved to a value 40 σ/cm. Furthermore, impregnating a high amount of annealed carbon black (40 wt. %) in a polymeric matrix resulted in a low electrical conductivity of 0.0034 σ/cm. Blending annealed carbon black into carbon fiber reinforced polymer (CFRP) resulted in alternating the electrical conductivity of the composite material. The surface conductivity of carbon fiber polymer was 2.5 σ (per square). However, the surface conductivity of impregnating 2 wt. % of annealed waste carbon black into CFRP was 13 σ (per square). The results also showed that addition of 5 wt. % of waste carbon black noticeably decreased the area specific resistance of CFRP from 199 to 98 mΩ.cm2. The through-plane thermal conductivity of CFRP increased as carbon black wt. % increased. The through plane-thermal conductivity increased by 78% when the waste carbon black loading reached 16 wt. %. However, loading the composite with waste carbon black resulted in decreasing the flexural strength. It is recommended to blend 5 wt. % of waste carbon black annealed at 1250°C into CFRP to provide enhancement in both the through-plane and surface electrical conductivity. The surface conductivity was enhanced by 80% when blending 5 wt. % of waste carbon black. The through plane resistivity reduced 51% by adding 5 wt. %of waste carbon black. However, the flexural strength was negatively affected with a reduction of 8% only by blending 5 wt. % of waste carbon black