Estimation of effect of gasoline quality improvement on reduction of air toxic emissions in Dhaka

Gasoline quality improvement alone can reduce total pollution load from vehicles to a considerable extent. A spreadsheet-based model has been developed in the present study to demonstrate this. An annual emission inventory for gasoline-driven vehicles was prepared with respect to volatile organic compounds, toxic air pollutants and nitrogen oxides using vehicle popula tion data, growth rate of vehicles and usage characteris-tics in Dhaka. Results of the present and projected air toxic emission inventory using planned improvement in gasoline quality reveal that an emission reduction of about 20% may be achieved. A significant reduction of about 60% in pollutants like benzene justifies gasoline quality improvement in a developing country like Bangladesh. Keywords: Exhaust volatile organic compounds, gaso-line quality, polycyclic organic matter, toxic air pollutant

Heat Transfer and Thermographic Analysis of Catalyst Surface during Multiphase Phenomena under Spray-Pulsed Conditions for Dehydrogenation of Cyclohexane over Pt Catalysts

Dehydrogenation of cyclohexane over Pt/alumite and Pt/activated carbon catalysts has been carried out for hydrogen storage and supply to fuel cell applications. An unsteady state has been created using spray pulsed injection of cyclohexane over the catalyst surface to facilitate the endothermic reaction to occur efficiently. Higher temperature of the catalyst surface is more favorable for the reaction, thus the heat transfer phenomena and temperature profile under alternate wet and dry conditions created using spray pulsed injection becomes important. IR thermography has been used for monitoring of temperature profile of the catalyst surface simultaneously with product analysis. The heat flux from the plate-type heater to the catalyst has been estimated using a rapid temperature recording and thermocouple arrangement. The estimated heat flux under transient conditions was in the range of 10-15 kW/m2, which equates the requirement for endothermic reactions to the injection frequency of 0.5 Hz, as used in this study. The analysis of temperature profiles, reaction products over two different supports namely activated carbon cloth and alumite, reveals that the more conductive support such as alumite is more suitable for dehydrogenation of cyclohexane

Circular Economy Pathways for Municipal Wastewater Management in India: A Practitioner’s Guide

The 2030 Water Resources Group is a unique publicprivate- civil society partnership that helps governments to accelerate reforms that will ensure sustainable water resource management for the long term development and economic growth of their country. It does so by helping to change the “political economy” for water reform in the country through convening a wide range of actors and providing water resource analysis in ways that are digestible for politicians and business leaders. The 2030 WRG was launched in 2008 at the World Economic Forum and has been hosted by the International Finance Corporation (IFC) since 2012

Production of hydrogen-rich gas via reforming of iso-octane over Ni–Mn and Rh–Ce bimetallic catalysts using spray pulsed reactor

The conversion of hydrocarbon fuels such as gasoline and diesel is a potential source for hydrogen production towards various fuel cell systems. A novel spray pulsed mode reactor to create alternate wet and dry conditions on the catalyst surface has been used in this study to enhance the rates of hydrogen production compared with the solid-gas phase reaction due to the improvement of the catalyst reactant contact. The production of hydrogen-rich gas by reforming of iso-octane (2,2,4-trimethylepentane) in the presence of steam and air has been studied at 600 and 700 LC over Ni–Mn and Rh–Ce bimetallic catalysts supported on alumina mesh. The feed rate of iso-octane was varied from 0.553 to 5.53 m mol min)1 by controlling pulse injection in terms of the width and frequency of injection of iso-octane. Based on the product analysis optimized condition for higher hydrogen production and high H2/CO ratio has been deduced. KEY WORDS: iso-octane reforming; hydrogen production; bimetallic catalysts; pulse spray injection

Pure phase LaFeO3 perovskite with improved surface area synthesized using different routes and its characterization

Three different wet chemistry routes, namely co-precipitation, combustion and sol–gel methods were used to synthesize LaFeO3 perovskite with improved surface area. The synthesized perovskite was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectrometer (EDS), Brunauer–Emmett–Teller (BET) nitrogen adsorption, ultraviolet diffused reflectance spectroscopy (UVDRS) and Fourier transform infrared (FTIR) spectroscopy techniques. Improved surface area was observed for all three methods as compared to the previously reported values. The perovskite synthesized using sol–gel method yields comparatively pure, crystalline phase of LaFeO3 and relatively higher surface area of 16.5 m2 g−1 and porosity. The material synthesized using co-precipitation method yielded other phases in addition to the targeted phase. The morphology of perovskite synthesized using co-precipitation method was uniform agglomerates. Combustion method yields flakes type morphology and that of sol–gel method was open pore type morphology. The selection of method for perovskite synthesis largely depends on the targeted application and the desired properties of perovskites. The results reported in this study are useful for establishing a simple scalable method for preparation of high surface area LaFeO3 as compared to solid-oxide method. Further, the typical heating cycle followed for calcinations resulted in relatively high surface area in the case of all three methods

Effective cleanup of CO in hydrogen by PROX over perovskite and mixed oxides

Preferential oxidation of CO (PROX-CO) from hydrogen has been carried out over various oxides and perovskite catalysts namely CeO2, CuLaO2eCeO2, La2CuO4. Further, effect of loading of a small quantity of Pt in catalysts 0.1 wt% Pt/CeO2, 0.1 wt% Pt/La2CuO4, 0.1 wt% Pt/CuLaO2eCeO2 was examined with respect to its activity for PROX-CO. In order to improve the surface area of La2CuO4 a chitosan complex method was used for synthesis. The catalysts were characterized using XRD, SEM and BET-SA techniques. Chitosan complex method results in pervoskite with pure phase, porous structure and higher surface area of 16.3 m2/g compared to that of 3.8 m2/g obtained by co-precipitation synthesis method. La2CuO4 exhibited a considerable activity for CO oxidation with conversion of 91.7%. Whereas, 0.1 wt% Pt/CuLaO2eCeO2 catalyst exhibited CO conversion of 94.1% and selectivity of 87.1% at reaction temperature of 320 _C. The improved CO/H2 selectivity may be attributed to the promotion of water gas shift reaction at the interface of Pt-metal oxide besides the relatively higher oxidation activity of the metal oxides. The catalysts reported in this study with relatively higher CO conversion and selectivity with lower value of l ¼ 0.3 exhibit potential for effective cleanup of hydrogen gas to remove CO for fuel cell applications

Catalytic preferential oxidation of carbon monoxide over platinum supported on lanthanum ferriteeceria catalysts for cleaning of hydrogen

Since hydrogen is produced by reforming of hydrocarbon it contains carbon monoxide (CO). In order to make hydrogen suitable for proton exchange membrane fuel cell application there is need to reduce concentration of CO less than 100 ppm. WatereGas-Shift reactions subsequent to reforming lower CO concentration in H2 to about 1e1.5% by volume. Preferential oxidation of CO (PROXeCO) using a catalyst is therefore important for further cleaning up of CO from H2. The catalyst in this study is platinum supported over lanthanum ferriteeceria (Pt/LaFeO3eCeO2) exhibits excellent activity of 99.8% and selectivity of 95.7% at a relatively lower temperature of 100 _C with an equivalence ratio of 3 for PROX eCO. The concentration of CO is reduced from 1% v/v in feed to ca. 30 ppm in product gas with rela-tively lower loss of hydrogen is the most significant achievement in this study. The catalyst is selective towards CO oxidation as the hydrogen loss is relatively low (ca. 3.8%) and there is no methane formation. The improvement in catalytic activity and selectivity is attributed to the strong metal support interaction and open morphology of catalyst. The results obtained in this study reveal the excellent catalytic activity by using LaFeO3eCeO2 as support for Pt catalyst

In-situ infrared thermographic analysis during dehydrogenation of cyclohexane over carbon-supported Pt catalysts using spray-pulsed reactor

Infrared thermography, a tool used for screening of active catalytic materials generally during the exothermic reactions has been used for thermal imaging during strong endothermic reaction of dehydrogenation of cyclohexane on Pt catalyst supported on active carbon cloth (CFF-1500s) sheets. A spray-pulsed mode was used for injection of atomized cyclohexane and to create alternate wet and dry condition on catalyst surface. The simultaneous product gas analysis and recording of the temperature profile of the catalyst surface using an IR camera was carried out. The production rate of hydrogen via endothermic dehydrogenation reaction is greatly dependent on the temperature of the catalyst surface. The observed change in the temperature profile at wet and dry conditions with varying pulse-injection frequency and corresponding product gas analysis reveals that the spray-pulse mode is useful in improving the catalyst activity. Further the reaction conditions were optimized using thermal profile data. KEY WORDS: IR thermography; cyclohexane dehydrogenation; hydrogen production; Pt catalyst; spray-pulse injection

Hydrogen delivery through liquid organic hydrides: Considerations for a potential technology

Carrying hydrogen in chemically bounded form as cycloalkanes and recovery of hydrogen via a subsequent dehydrogenation reaction is a potential option for hydrogen transport and delivery. We have earlier reported a novel method for transportation and delivery of hydrogen through liquid organic hydrides (LOH) such as cycloalkanes. The candidate cycloalkanes including cyclohexane, methylcyclohexane, decalin etc. contains 6 to 8 wt% hydrogen with volume basis capacity of hydrogen storage of 60e62 kg/m3. In view of several advantages of the system such as transportation by present infrastructure of lorries, no specific temperature pressure requirement and recyclable reactants/products, the LOH definitely pose for a potential technology for hydrogen delivery. A considerable development is reported in this field regarding various aspects of the catalytic dehydro-genation of the cycloalkanes for activity, selectivity and stability. We have earlier reported an account of development in chemical hydrides. This article reports a state-of-art in LOH as hydrogen carrier related to dehydrogenation catalysts, supports, reactors, kinetics, thermodynamic aspects, potential demand of technology in field, patent literature etc

Hydrogen production by reforming of iso-octane using spray-pulsed injection and effect of non-thermal plasma

Production of hydrogen-rich gas via reforming of hydrocarbons is desired for onboard supply of hydrogen to PEMFC applications. Iso-octane is used in this study to simulate the reforming of gasoline under autothermal conditions using a steam/carbon ratio equal to 1 and an equivalence ratio equal to 0.32. The reforming has been carried out at temperatures of 600 and 700 8C on Ni–Mn, Ni–W and Rh–Ce catalysts supported on alumina mesh. A novel spray-pulsed reactor with fine nozzle is used for providing atomized iso-octane in pulses. The alternate wet and dry conditions improved the catalyst-reactant contact and enhanced the hydrogen production rate. The iso-octane dose was controlled by variation in pulse injection frequency (0.001, 0.01, 0.05 and 0.1 Hz) and pulse width (2 and 6 ms). The maximum hydrogen yield obtained is 4 mol of hydrogen per mole of iso-octane. Further, the effect of non-thermal plasma in combination with catalyst on reaction was tested under spray-pulse injection of iso-octane. # 2004 Elsevier B.V. All rights reserved. Keywords: Iso-octane reforming; Hydrogen production; Bimetallic catalysts; Pulse spray injection; Plasma-catalytic syste