Bituminous Coal Tar Research Articles

Characterization of glass fiber bituminous coal tar reinforced Polymer Matrix Composites for high performance applications

Composite materials are better and are used than other conventional structural materials because they offer superior performance, high specific strength and stiffness, excellent fatigue resistance, low weight and design flexibility. These above-mentioned properties have become the winning alliance that impels fibrous composite materials into new arenas. Glass Fiber/Epoxy Polymer Reinforced Plastic composites are widely used over other orthodox engineering materials in the Automobile and Aerospace industry owing to the improved properties. In the present work, an attempt has been made to study the properties of combination of unidirectional E-glass Fibers and carbon reinforced matrix (Bituminous coal tar + Epoxy) with an increase in weight proportions (wt%) of coal tar from 0 wt% till 10 wt%. The properties of cryogenically exposed Glass - Fiber Bituminous carbon coal polymer composites (GBCPC) are studied and compared with that of unexposed. The composites density was found to increase with bituminous coal tar in matrix. The Hardness, Ultimate Tensile Strength and Inter-Laminar Shear Strength of the composites witnessed an increase with greater matrix reinforcement wt% and after cryogenically exposure hardness and ultimate strength have witnessed an increase but Inter-Laminar Shear Strength shows phenomenological behavior, it can be due to micro cracks as well as delamination in the composites due to thermal residual stresses. The sliding wear test was conducted using Taguchi L16 method. The dry sliding wear of the cryogenically exposed specimen displayed higher resistance to wear.

Synthesis of Mesoporous Carbons from Bituminous Coal Tar Pitch Using Combined Nanosilica Template and KOH Activation

Mesoporous carbons (MCs) facilitate mass transport in pore networks and enhance the performance of porous carbon. By combining a nanosilica template with KOH activation, highly porous MCs with BET specific surface areas (SBET) greater than 1000 m2/g were synthesized from unmodified commercial coal tar pitch. The MCs had a honeycomblike morphology with randomly arranged macropores. An increase in template amount resulted in an increase in pores larger than 20 nm, the size of silica template. An MC sample activated at 850 °C for 2 h with a KOH-to-carbon ratio of 2.7:1 and a pitch-to-template ratio of 3:1 had an SBET value of 1366 m2/g, 65 vol % mesopores, 19 vol % macropores, and an average pore diameter of 25 nm. Whereas the silica template was largely responsible for macropores and large mesopores, KOH created new micropores and enlarged existing pores through KOH–carbon reactions. Moreover, KOH enhanced the formation of carbonyl, carboxyl, and lactonic groups on the carbon surface. The feasibility of synthesizing MCs from an unmodified commercial carbon precursor with a simpler route was demonstrated.

Preparation and characterization of activated carbons from impregnation pitch by ZnCl 2

Using an impregnation pitch from bituminous coal tar (OP) supplied by Industrias Químicas del Nalon Company as raw material, two phases (isotropic and anisotropic) have been obtained. The latter was used as precursor for the preparation of activated carbons. First, a chemical activation process was carried out with ZnCl 2 as activating agent. The process was conducted at different concentrations and temperatures and by means of impregnation with solid zinc chloride. Optimal values were obtained for samples prepared by using a ZnCl 2:pitch ratio equal to 3:1 (sample AZn3). Next, this sample was thermally treated at two different temperatures, i.e., 700 and 800 °C. A lose of specific surface area, microporosity and mesoporosity was observed with respect to sample AZn3, such a lose being more remarkable as temperature increased. Moreover, impregnation of the anisotropic phase of the original pitch with an aqueous solution of ZnCl 2 followed by thermal treatment resulted in a poorly developed surface area and porous texture, probably due to the presence of Zn complexes, which interfere with the activation process.

Neue horizonte für die chemie

The term ‘sustainable development’ is defined and discussed with regard to its significance and its application in the field of chemistry. This is presented using the synthetic organic chemistry as an example. A review of the history of chemistry indicates clearly the necessity for further developments in the course of concepts involving sustainability. Following the eras of bituminous coal tar and mineral oil in both of the two past centuries, a search for new raw materials and a reduction in the global ecotoxicological potential for danger is being strived for. Critical contemplations are mandatory in order to avoid making this term ‘persistence’ into a keyword. Consequently, one must take into consideration the field of research and development as well as reflecting about the classification of chemical and scientific research projects, and their political as well as social relationships. Aside from the new methods of synthesis, this will also require the formulation of other decision-relevant criteria.

Chemical recycling of mixed plastics of pyrolysis

AbstractMost plastics are produced from oil and have a high potential as hydrocarbon sources for the chemical industry. Pyrolysis is a practicable way to pyrolyze mixed plastics. The fluidized bed pyrolysis has turned out to be particularly advantageous. Twenty‐five to 45% of product gas with a high heating value and 30–50% of an oil rich in aromatics could be recovered. The oil is comparable to that of a mixture of light benzene and bituminous coal tar. Up to 60% of ethene and propene are produced by using mixed polyolefins as feedstock. Under appropriate conditions the pyrolysis could be successful on the market. © 1995 John Wiley & Sons, Inc.

Pyrolysis with respect to recycling of polymer

AbstractMost plastics are produced from oil and have a high potential as hydrocarbon sources for the chemical industry. Pyrolysis is a practicable way to pyrolyze mixed plastics. The fluidized bed pyrolysis has turned out to be particularly advantageous. 25 to 45 percent of product gas with a high heating value and 30 to 50 percent of an oil rich in aromatics, could be recovered. The oil is comparable to that of a mixture of light benzene and bituminous coal tar. Up to 60 percent of ethene and propene are produced by using mixed polyolefins as feedstock. Under appropriate conditions the pyrolysis could be successful on the market.

Structural features of coal tar maltenes by FT-IR spectroscopy

Four bituminous coal tar maltenes were fractionated into saturates, aromatics, and polars by extrography and complexation chromatography on a silica gel/silver nitrate column. For each fraction, the integral absorptivities for aliphatic and aromatic hydrogen were determined by using FT-IR and 1 H NMR spectroscopy. Whereas the aromatic integral absorptivities have been found relatively independent on the polarity of the fractions, the values of the aliphatic integral absorptivities decreased from saturates to polars. This is most likely due to the structural inconsistency of the fractions and, simultaneously, the changes in dipole moments of the C-H bonds in α-position to the aromatic ring

Determination of polyaromatic hydrocarbons in high-boiling fractions of bituminous coal tar

A procedure is proposed that allows determination of the content of polyaromatic hydrocarbons in coal conversion products. It involves dialysis, extraction and g.c.-m.s. and SEC-g.p.c.-m.s. analysis. The contents of aromatics with a wide range of molecular weights can be determined. The procedure is suitable for high-boiling coal conversion products.

Thermal recycling of polymers

As most plastics are produced from oil, the recycling of plastic and rubber wastes is of increasing importance. Systems for the pyrolysis of plastic wastes with complete exclusion of oxygen use melting vessels, rotary kilns or fluidized bed processes. The pyrolysis of plastic wastes, scrap tyres and other polymeric materials in a fluidized bed has been carried out at the University of Hamburg, based on a three-step scale-up programme (laboratory plant 100 g/h, pilot plant 30 kg/h and prototype plant 150 kg/h). Up to 50% of the input plastic material is converted into liquid hydrocarbons. The product spectrum is comparable to that of a mixture of light benzene and bituminous coal tar, consisting of about 95% aromatics. By addition of lime it became possible to absorb completely the hydrogen chloride evolved from poly(vinyl chloride). The technology in a fluidized bed allows the pyrolysis of whole tyres to include aromatic compounds, gas, carbon black and steel wire. A first commercial demonstration plant using the fluidized bed process with an annual plant capacity of 5000–10,000 t has been erected.

Catalytic pyrolysis of a coal tar in a fixed-bed reactor

The product yields from cracking a bituminous coal tar in a fixed-bed reactor were determined at various temperatures in the presence and absence of various packing materials. Some synthetic and natural zeolites showed strong catalytic activity, but those with small pore diameters were much less active. Linde zeolite LZ-Y82 was very effective in converting tar to chars and gases in the temperature range 400-500 C. Among the factors involved for catalytic effectiveness are: an effective pore size >0.7 nm; a large internal surface accessible to the tar vapor; and a large number of strongly acidic sites.

Renal significance of hexachlorobutadiene: Duprat, P. & Gradiski, D. (1978) Percutaneous toxicity of hexachlorobutadiene. Acta pharmac. tox.43, 346

This chapter discusses monomers in coal macromolecules. In a study described in the chapter, some coals were demineralized under nitrogen using the standard sequential HCl and HF techniques. The dried residues were extracted at reflux under nitrogen with pyridine. The residues and extracts were worked up with a standard procedure. The DCIMS studies were done on a Kratos MS50 triple analyzer with isobutane as the reagent gas. The solids and extracts were heated in the source on a small platinum wire coil from 200°C to 700°C at 100°C/min, and the source was heated at 200°C. To facilitate comparison with previously reported FABMS data, vacuum tars prepared in a batch mode were examined. Spectra from FABMS, LDMS, and DCIMS obtained on Upper Freeport mv bituminous coal tar were compared. A broader mass distribution was obtained with FAB than either laser desorption or chemical ionization where there is was a small number of peaks of low intensity below m/z = 200.

Gas-liquid chromatographic analysis of C 10-C 16n-paraffins, isoparaffins and α-olefins in a low-temperature coal tar

21 C 10-C 16 hydrocarbons, 7 each of n-paraffins, 2-methyl alkanes and α-olefins, were identified in a low-temparature bituminous coal tar by means of gas-liquid chromatography. Quantitative determinations were made on all of these constituents. It was found that the curves for the plots of logarithms of relative retention against normal boiling points for C 10-C 16 n-paraffins and α-ole fins are parallel. A similar parallel curve for the 2-mathyl alkane series was derivred, using the Known point for 2-methyl decane. This correlation curve was used for the identification of several 2-methyl alkalnes. Naphthenes and trans-olefins were found in small amounts.

Gas-liquid chromatographic analysis of aromatic hydrocarbons boiling between 202° and 280° in a low-temperature coal tar

Gas—liquid chromatography, coupled with infrared and ultraviolet spectrophotometry, was used to analyze aromatic hydrocarbons boiling between 202° and 280° in the neutral oil portion of a low-temparature bituminous coal tar. A total of 48 compounds was identified, of which 20 were alhylnaphthalenes. Of these compounds, nine had also been mentioned in a previous report. Quantitative determinations were made on nearly all of the components. The analysis, especially from a quantitative: standpoint, is by far the most detailed one carried out to date for the alkylnaphtlialcne cut of a low-temperature coal tar. It was shown that alkylnaphthalenes with equal numbers of carbon atoms in tlieir alkyl groups displayed a linear relationship between log relative retention and normal boiling point, a situation similar to that for the alkylbenzene series, and that the values for the C 11, C 12 and C 13 alkylnaphthalenes lie on three parallel lines. Examples of the utility of these correlations arc given.

Gas-liquid chromatographic analysis of aromatic hydrocarbons boiling up to 218° in a low-temperature coal tar

52 Aromatic hydrocarbons boiling up to 218° were identified in a low-temperature bituminous coal tar by means of gas-liquid chromatography and infrared spectrophotometry, 27 of these for the first time. Quantitative determinations were made on 43 compounds boiling up to 200°. It was shown that alkylbenzenes with equal numbers of carbon atoms in their alkyl groups exhibit a linear relationship between log relative retention and normal boiling point, and that the C 8, C 9, C 10, C 11, and C 12 alkylbenzenes lie on five parallel lines whose separation from each other is related to the logarithm of the number of carbon atoms in the alkyl group. Examples of the accuracy and utility of these novel correlations are presented.

Identification and Determination of Low-Boiling Phenols in Low Temperature Coal Tar

Low-boiling phenols in a low temperature bituminous coal tar distillate have been identified and quantitatively determined by gas-liquid partition chromatography. These phenols were also determined by the conventional technique of fractional distillation, followed by infrared analysis. Comparison of the two independent techniques of GLPC and IR was made. Phenol, cresols, xylenols, and ethylphenols were included in the analyses.