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Acid mine water was treated with fly ash zeolite (FAZ), followed by different active chemicals to know its suitability for crops. Acid mine drainage (AMD) was obtained from Gorbi abandoned opencast mines of Singrauli, Northern Coalfields (NCL), India. The AMD was treated with 20 g/l dosing of fly ash zeolite, followed by different precipitating chemicals, using different doses of Ba(OH)2, BaCO3 and Ca(OH)2. The doses of 1.0 g/l Ba(OH)2, 1.5 g/l BaCO3 and 0.5 g/l Ca(OH)2 were used. The treatment with FAZ, followed by 1.0 g/l of Ba(OH)2, converted the water quality of AMD to the permissible level. The electrical conductivity (EC), percentage of sodium and metals found at the permissible level indicated the suitability of mine water for agriculture use. AMD treated directly with 1.0 g/l of Ba(OH)2 was found unsuitable for agriculture use. The treatment with FAZ and followed by BaCO3 (1.5 g/l) explained that the water quality was not at the permissible level and unsuitable for agriculture use. AMD treated directly with 1.5 g/l of BaCO3 was also found unsuitable for agriculture. The treatment with FAZ, and followed by 0.5 g/l dosing of Ca(OH)2, also showed water quality not at the permissible level. The conductivity, total salt content (as TDS) and sulfate values increased or decreased minimally, and there was an increase in the concentrations of total hardness and calcium hardness in the final treated mine water. The direct dosing with 0.5 g/l of Ca(OH)2 made AMD unsuitable for agriculture use. Treatment with 20 g/l FAZ followed by 1.0 g/l of Ba(OH)2 produced the treated AMD suitable for agriculture use.

Four coal samples from Jharia basin, India are treated with nitric acid in glacial acetic acid and aqueous media to find out the chemical, petrographic and spatial structure of the organic mass by X-ray diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FTIR) techniques.X-ray parameters of coal like interlayer spacing (d002), crystallite size (Lc), aroamticity (fa), average number of aromatic layers (Nc), and coal rank (I26/I20) have been determined using profile-fitting software. Considerable variation is observed in treated coals in comparison to the demineralized coals. The d002 values of treated coals have increased in both the media showing increase in disordering of organic moieties. A linear relationship has been observed between d002 values with the volatile matter of the coals. Similarly, the d002 values show linear relationship with Cdmf contents for demineralized as well as for the treated coals in both the media. The Lc and Nc values have decreased in treated coals corresponding to demineralized coals. The present study shows that nitration in both the media is capable of removing the aliphatic side chains from the coals and aromaticity (fa) increases with increase in rank and shows a linear relationship with the vitrinite reflectance. The corresponding I26/I20 values are least for treated coals in glacial acetic acid medium followed by raw and then to treated coals in aqueous medium.FTIR studies show that coal arenes of the raw coals are converted into nitro-arenes in structurally modified coals (SMCs) in both the media, the corresponding bands at 1550 – 1490 cm-1 and 1355 – 1315 cm-1 respectively. FTIR study confirms that nitration is the predominant phenomenon, though, oxidation and nitration phenomena takes place simultaneously during treatment with nitric acid to form SMCs. In comparison to raw coals, the SMCs show higher aromaticity and may be easily converted to coal derived products like activated carbon and specialty carbon materials.

A series of silica doped alumina (SDA) [Si-Al2O3] having high surface area and narrow pore size distribution are synthesized with varying amount of silica and used as a support material to facilitate incorporation of Co, Mg and Zr into it. These supported Co-Mg-Zr/SDA materials are used as catalysts for selective synthesis of middle distillate through Fischer-Tropsch synthesis (FTS) reaction. Trace quantity (∼0.05 wt %) of ruthenium (Ru) has also been used as a promoter for Co -Mg-Zr/SDA catalyst to improve the reducibility, selectivity towards middle distillate and increasing the catalyst life. The detail characterizations of catalysts indicate that Ru promotion and narrow pore size distribution facilitate CO conversion and middle distillate selectivity. Synthetic syngas of composition (H2 = 28.63%, CO = 14.27%, CO2 = 9.25%, CH4 = 1.0%, and N2 = 46.85%), which may be obtained after coal gasification and H2 enrichment process by water gas shift (WGS) reaction has been used as a reactant for middle distillate synthesis. The role of Ru and silica proportion on Co-Mg-Zr/SDA is investigated through Low Temperature Fischer-Tropsch (LTFT) synthesis at 220 °C temperature and 30 bar pressure. The surface acidity of the Ru/Co-Mg-Zr/SDA catalyst plays an important role for middle distillate selectivity and CO conversion. To determine the durability of catalysts, 300 h continuous experimental run has been conducted at Gas Hourly Space Velocity (GHSV) of 500 h−1. Among the catalysts in the present study, Ru/Co-Mg-Zr/SDA(7.5) catalyst shows highest CO conversion (94.2%) with 85% selectivity of C6-C19 hydrocarbon.

In the era of sustainable chemistry the development of nanocatalysis has drawn special attention. Here we report the preparation of nanocrystalline, mesoporous cerium-tin oxide solid solutions and tested for selective oxidation of benzyl alcohol, cinnamyl alcohol, 4-methylbenzyl alcohol, 2-octanol, and geraniol using molecular oxygen as an oxidant. Among different mesoporous supports with Ce/Sn compositions (98/2, 95/5, 90/10 and 80/20, the highest activity was found for the Ce-Sn mixed oxide (Ce/Sn = 95/5) supported gold nanoparticles. The microkinetic study shows that there was no mass transfer limitation in three phase catalytic system. The supports and the corresponding gold catalysts were extensively characterized by N2 physisorption, XRD, H2-TPR, NH3-TPD, TEM, XPS, RAMAN and XAFS techniques. The nanocrystalline solid solution of CexSn1-xO2 was detected by XRD analysis. The presence of oxide vacancy was confirmed by XPS and RAMAN studies. The reducibility of Ce-Sn mixed oxide support increased upon gold deposition which was confirmed by H2-TPR techniques. The TPD study indicates the alteration of acid-basic sites of the CeO2 oxide upon incorporation of tin and gold nanoparticles. The cooperative role between the gold species and the ceria-tin support has been observed while correlating the catalytic activity results with the characterization studies.

The present study focuses on the catalytic conversion of syngas (CO + H2) through Fischer–Tropsch (FT) route using two identically prepared 0.1 wt.% palladium promoted Mesoporous Alumina (MA) and SBA–15 supported Co (15 wt.%) catalysts. The Fischer–Tropsch activity is performed in a fixed bed tubular reactor at temperature 220 °C and pressure 30 bar with H2/CO ratio ~2 having Gas Hourly Space Velocity (GHSV) of 500 h−1. Detail characterizations of the catalysts are carried out using different analytical techniques like N2 adsorption-desorption, Temperature-programmed reduction with hydrogen (H2-TPR), Temperature-programmed desorption with NH3 (NH3-TPD), X-Ray Diffraction (XRD), and Transmission Electron Microscopy (TEM). The results show that the SBA–15 supported catalyst exhibits higher C6–C12 selectivity (57.5%), and MA supported catalyst facilitates the formation of higher hydrocarbons (C13–C20) having a selectivity of 46.7%. This study attributes the use of both the support materials for the production of liquid hydrocarbons through FT synthesis.

Temperature programmed reduction (TPR) is one of the techniques for obtaining information about phases or bulk species in heterogeneous catalysts. Information from TPR analysis can give insights about phase-support interaction and extent of reduction of the phases at different temperatures. TPR technique is a common tool in the characterisation of cobalt based Fischer-Tropsch (FT) catalysts. However, interpretation of TPR profiles of γ-alumina supported cobalt FT catalysts had been characterised with different views on the nature of phases and reduction processes involved. In this report, we use reduction behaviour of unsupported Co3O4 to gain insight for more explicit analysis of TPR profiles of γ-alumina supported Co3O4 catalysts. The transition Co3O4 → CoO → Co in γ-alumina supported catalysts prepared with wet impregnation with aqueous cobalt nitrate and calcined at temperatures ≤ 350°C gave reduction peaks at 300 to 350°C. Reduction peaks at 500 to 600°C were due to Co-Al mixed oxide phases; most likely Co2AlO4 and probably routes formation of the mixed oxide were also discussed. Consideration of tendency of dissolution of γ-alumina during the impregnation of metal salt is instructive toward achieving higher reducibility of Co3O4 in the design of cobalt based Fischer-Tropsch catalysts. Key words: Temperature programmed reduction (TPR) profile, calcinations, Co3O4, γ-Al2O3, Fischer-Tropsch catalyst.

The present study demonstrates the effect of zirconium promotion on Fe-Zn-based catalysts to boost the active sites of Fischer-Tropsch (FT) catalysts. The catalysts are also promoted by Cu and Ca and the active sites are examined using Temperature-Programmed Reduction (TPR) with H2 and CO and Temperature-Programmed Desorption (TPD) with NH3 and CO2 . The results are presented as a comparative study between Fe-Zn- and Fe-Zn-Zr-based catalysts. The results show that addition of Zr to Fe-Zn catalysts increases the availability and dispersion of the precursor to the active sites and promotion with Cu and Ca independently and synergistically enhances reduction of Fe-Zn-Zr-based catalysts. The presence of Ca promotes carburisation, while Cu inhibits carburisation. The impact of the Ca and Cu on the surface acidity/basicity is governed by the nature of the interaction between the phases in the catalysts. The extent of reduction reflects the availability and dispersion of the precursor to the active phase, while the extent of carburisation will impact on the selectivity of the catalysts.

Activation of molecular O2 by metal or metal oxide nanoparticles is an area of recent research interest. In this work, for the first time, we report that indium oxide nanoparticles of

Atom efficient synthesis of various value added products has been focused as an intense research area after Kyoto protocol. Styrene epoxidation is a challenging reaction as styrene epoxide is an important monomer for large number of polymers. It has been found that surface acidity and redox property of the catalyst has a major contribution to the catalytic activity for oxidation reaction. In this study Co-HMS-X catalyst was prepared and characterized by BET surface area and porosity measurement, SAXS, SANS, FESEM, HRTEM, UV–vis spectra, FTIR, 29Si NMR, H2-TPR and NH3-TPD techniques. It is observed that 5 mol% Co-HMS-X showed highest catalytic activity for styrene epoxidation reaction using molecular O2 as an oxidant. Interestingly it is found that among three different dopant (Al, Ga, Tl), the Ga promoted Co-HMS-X catalyst (Si:Co:Ga = 100:5:1.25) showed highest catalytic activity in terms of styrene conversion (100%) and styrene epoxide selectivity (68%). The unusual trend of Al, Ga and Tl towards the activity of Co-HMS-X (5 mol%) catalyst has been discussed from the results obtained in the H2-TPR and NH3-TPD study.

Hydrogen is considered as the fuel for next generation and extensive research is being pursued for search of new techniques for hydrogen production from renewable sources. There is a diverse collection of hydrogen production processes at their different stages of development. This review paper analyzes the industrial and emerging hydrogen production technologies. These processes include steam methane reformation, partial oxidation, autothermal reforming, steam iron, plasma reforming, thermochemical water splitting and biological processes. Till date, steam reformation of methane is the most used industrial technique and its efficiency can go up to 85%. It meets up to 50% of total hydrogen consumption in the world. Continuous research is going on to enhance production yield as well as to improve the process economics. Considerable work is going on about sorption enhanced reforming and membrane reactor for this purpose. Partial oxidation and autothermal reforming processes are the other two processes which are also used for industrial. The most sought process is the thermochemical water splitting using sunlight. Several research institutes are engaged in the development of hydrogen production technologies using renewable sources. Plasma reformation and biological processes are intensively worked out throughout the globe. The present article reviews the recent developments in industrial techniques which will lead to enhancement of hydrogen production. The non-conventional techniques are described in this article as emerging techniques, which are the promising approaches for hydrogen production from biomass, an abundant, clean and renewable source.

Fischer–Tropsch technology has become a topical issue in the energy industry in recent times. The synthesis of linear hydrocarbon that has high cetane number diesel fuel through the Fischer–Tropsch reaction requires syngas with high H 2 /CO ratio. Nevertheless, the production of syngas from biomass and coal, which have low H 2 /CO ratios or are CO 2 rich may be desirable for environmental and socio-political reasons. Efficient carbon utilization in such H 2 -deficient and CO 2 -rich syngas feeds has not been given the required attention. It is desirable to improve carbon utilization using such syngas feeds in the Fischer–Tropsch synthesis not only for process economy but also for sustainable development. Previous catalyst and process development efforts were directed toward maximising C 5+ selectivity; they are not for achieving high carbon utilization with H 2 -deficient and CO 2 -rich syngas feeds. However, current trends in FTS catalyst design hold the potential of achieving high carbon utilization with wide option of selectivities. Highlights of the current trends in FTS catalyst design are presented and their prospect for achieving high carbon utilization in FTS using H 2 -deficient and CO 2 -rich syngas feeds is discussed.

The treatment of coal with nitric acid in aqueous and non-aqueous media introduces changes in the chemical and spatial structure of the organic mass. Four coals of different rank have been treated with nitric acid in aqueous and glacial acetic acid media for assessing the changes in the structural parameters by the X-ray diffraction (XRD) technique. Slow-scan XRD has been performed for the raw and treated coals, and X-ray structural parameters (d002, Lc, and Nc) and aromaticity (fa) have been determined by profile-fitting software. Considerable variation of the structural parameters has been observed with respect to the raw coals. The d002 values have decreased in aqueous medium but increased in acetic acid medium; however, Lc, Nc, and fa values have increased in aqueous medium but decreased in acetic acid medium. It is also observed that considerable oxidation takes place during nitric acid treatment in aqueous medium, but nitration is the predominant phenomenon in acetic acid medium. Disordering of the coal structure increases in acetic acid medium, but a reverse trend is observed in the aqueous medium. As a result, structurally modified coals (SMCs) are derived as new coal-derived substances. 15 refs., 6 figs., 3 tabs.

EAU:ENERGIE+AAU; Integration of electricity generation with liquid fuel production is a viable strategy towards maximising coal utilisation and hydrocarbon supply. Herein we report on catalyst design for process intensification and optimisation of electricity and hydrocarbon production from coal. Low temperature Fischer-Tropsch synthesis with Fe-Zn (Zn/Fe ratio 0.25) based catalysts using H-2-deficient syngas feed displayed unprecedented low CO2 selectivity. Promotion of the Fe-Zn with Cu and Ca afforded Fischer-Tropsch product distributions that are typical of high temperature Fischer-Tropsch synthesis. The present report provides foundation for design of iron based catalyst that can compete with cobalt based once in terms of low CO2 selectivity. (C) 2013 Elsevier Ltd. All rights reserved.

Cu–Mn spinel oxide catalyst has been investigated for the ligand-free Huisgen [3+2] cycloaddition. The copper(I) species required in the cycloaddition reaction has been stabilized in the tetrahedral site of the spinel without the need of a stabilizing agent. The new catalyst is robust and can be reused several times under MW conditions with negligible loss in catalytic activity.