NOPR Collection:

A review on performance, emission and combustion characteristics of a diesel engine fuelled with various vegetable oil

2018-06-15T06:13:18Z

Title: A review on performance, emission and combustion characteristics of a diesel engine fuelled with various vegetable oil Authors: Asokan, M A; Vijayan, R; Prabu, S Senthur Abstract: In the present scenario, world energy consumption is increasing rapidly every year because of the increasing trend of modernization and industrialization. Crude oil is the major source for producing energy, results in the degradation of the environment due to fossil fuel combustion. Moreover, the combustion products like carbon di-oxide (CO₂), sulphur di-oxide (SO₂), and nitrogen oxide (NO_X) causes global warming.Crude oil depletes every year, to satisfy the energy demands, the crude oil is imported. The environmental problems caused by the indiscriminate use and scarcity of petroleum are the major factor to explore renewable energy resources. The idea of vegetable oil as a fuel to run diesel engines has been on the world stage over a century ago. Vegetable oil is an alternative fuel as a source of energy has been receiving great attention among the researchers because of its renewability, biodegradability, non-toxic and better quality of exhaust gas emissions.A lot of edible and inedible vegetable oils which canbe exploited for substitute fuel as diesel fuel, i.e., jatropha, karanja, rubber seed, cottonseed, palm oil, sun flower oil, rape seed oiland neemoils etc., has been selected and discussed the performance, combustion and emission characteristics of diesel engine under the variousworking conditions. Page(s): 225-234

Effect of the solid/liquid ratio on zinc and cadmium uptake on natural and iron-modified zeolite - Batch scale design

2018-06-15T06:10:26Z

Title: Effect of the solid/liquid ratio on zinc and cadmium uptake on natural and iron-modified zeolite - Batch scale design Authors: Ugrina, Marin; Medvidović, Nediljka Vukojević; Trgo, Marina Abstract: Zinc and cadmium uptake on natural (NZ) and iron-modified zeolite (IMZ) has been investigated through the two sets of experiments, first one with varying S/L ratios at a constant initial metal concentration and second one with different initial metal concentrations at a single S/L ratio. Results confirm the importance of choosing an optimum S/L ratio in achievement of the maximum removal efficiency with the lowest zeolite mass. Two different methods for the design of batch reactor have been applied to overcome the effect of the S/L ratio. The first approach applied the operating line method with the Dubinin-Radushkevich isotherm, and the second one applied the Rayleigh's method of dimensional analysis. The excellent agreement between predicted and experimentally obtained results for the amount of metal removed per gram of zeolite as well as error functions confirm the applicability of both methods in the batch scale design independently of the S/L ratio. Page(s): 235-245

Kinetics, equilibrium and thermodynamics studies on Cd(II) removal from aqueous solution by magnesite tailing

2018-06-15T06:07:42Z

Title: Kinetics, equilibrium and thermodynamics studies on Cd(II) removal from aqueous solution by magnesite tailing Authors: Erol, Seda; Özdemir, Mine Abstract: Magnesite tailing for the removal of Cd(II) from aqueous solutions has been investigated using batch process. The effects of various parameters such as initial pH, adsorbent dosage, contact time and temperature on the removal of Cd(II) have been investigated. Kinetic models are applied to describe the adsorption kinetics of Cd(II) onto magnesite tailing. The adsorption kinetics follows well the pseudo second order kinetic model. The Langmuir, Freundlich and D-R isotherm models have been used for the analysis of adsorption equilibrium. The Langmuir isotherm model fits the equilibrium data. The monolayer adsorption capacity of magnesite tailing is found to be 38.46 mg/g at 45°C. The thermodynamic parameters show that the adsorption process is feasible, spontaneous and endothermic. The Cd(II) - magnesite tailing interactions are confirmed by the Scanning electron microscope (SEM) and the Fourier transform infrared spectroscopy (FTIR). A single stage batch adsorber was designed for different adsorbent dosage using Langmuir isotherm. It is determined that approximately 99% of Cd(II) from aqueous solution could be removed at a pH value of 6, an adsorbent dosage of 0.3 g / 50 mL solution, a contact time of 24 h, an initial solution concentration of 10 mg/L and a temperature of 25°C. The results indicate that magnesite tailing could effectively be used for the removal of Cd (II) from aqueous solutions. Page(s): 246-254

Comparative studies on the removal of chromium(VI) from aqueous solutions using raw and modified Citrus Limettioides peel

2018-06-15T05:58:19Z

Title: Comparative studies on the removal of chromium(VI) from aqueous solutions using raw and modified Citrus Limettioides peel Authors: Sudha, R; Premkumar, P Abstract: Citrus Limettioides peel (CLPC) has been modified with sulphuric acid to increase the quantity of sulphonic acid groups improving its metal adsorption capacity. The effect of various parameters such as solution pH, contact time, adsorbent dose and presence of other cations and anions under ambient conditions along with raw citrus limettioides peel (CLP) has been studied. According to the experimental results, the optimal equilibrium time and pH for Cr(VI) ions are found to be 3 h and 2.0 for CLPC and CLP, respectively. The equilibrium data agree well with Langmuir model, which confirm the monolayer coverage of Cr(VI) ions onto CLPC and CLP. The Langmuir monolayer adsorption capacity of the CLPC is found to be 176.50 mg/g which is significantly about 1.8 times greater than that of CLP (99.50 mg/g) at 300 K. The thermodynamic analysis reveals that the adsorption process was spontaneous and exothermic in nature. The kinetic data follow pseudo-second order model with film diffusion process. A single-state batch adsorber has been designed to estimate the amount of adsorbent required to treat the known volume of the effluent using the Langmuir adsorption isotherm. Regeneration study show that CLPC could be effectively utilized for the removal of Cr(VI) ions for seven cycles of operation under study when compared with CLP. Page(s): 255-265