Time filter

Source Type

Doha, Qatar

Halder S.,Tata Consultancy Services Ltd. | Sakthivel S.,TCE QSTP LLC | Jayaraj K.M.,Tata Consultancy Services Ltd. | Gupta P.D.,Tata Consultancy Services Ltd.
Chemical Engineering Communications | Year: 2014

Studies were made to determine the influence of different reaction temperatures and residence times on biodiesel yield by transesterification of karanja oil (Pongamia pinnata) in the presence of methanol using a solid acid heterogeneous catalyst in a continuous process. Recycle runs were conducted by further transesterification of the organic phases (first run mixture of methyl ester and unconverted oil) in the presence of methanol under similar conditions. High-pressure liquid chromatography (HPLC) reveals poor biodiesel yield even with an increase in the reaction temperature and residence time in the first run. Biodiesel yield obtained from the recycle runs, however, was greatly increased over that of the first-run biodiesel yield. Recycle transesterification at a reaction temperature of 240°C and residence time of 50 min gives a maximum yield value of 97.74%. Consequently, irrespective of the presence of high free fatty acids and other impurities in karanja oil, recycling the organic phase of the first run significantly enhances the biodiesel yield. © 2014 Copyright Taylor and Francis Group, LLC. Source

Sakthivel S.,TCE QSTP LLC | Halder S.,Tata Consultancy Services Ltd. | Gupta P.D.,Tata Consultancy Services Ltd.
International Journal of Ambient Energy | Year: 2013

Response surface methodology was used to optimise the process parameters for biodiesel production by transesterification of Jatropha curcas oil, which contains more than 12% free fatty acid (FFA). A solid heterogeneous catalyst was developed and transesterification of the Jatropha curcas oil was carried out in packed bed reactor. The process operating variables, namely residence time, reactor temperature and molar flow ratio on the yield of biodiesel was studied and optimised. Statistical analysis of the results showed that the linear and quadric terms of these three variables had significant effects. The mathematical model and the optimum values of the process parameters are reported. Verification experiments confirmed the validity of the predicted model. © 2013 Copyright Taylor and Francis Group, LLC. Source

Chandiran A.,Pondicherry Engineering College | Anandan N.,Pondicherry Engineering College | Sakthivel S.,TCE QSTP LLC
Tribology - Materials, Surfaces and Interfaces | Year: 2012

The objective of this study is to investigate the enhancement of tool life and wear resistance with a physical vapour deposition (PVD) process applied using aluminium chromium nitride (AlCrN) and titanium nitride (TiN) coating on carbide inserts. Flank wear experiments are carried out on a computer numerically controlled (CNC) machine under wet conditions with both the coated inserts. Effectiveness of the coating on the tool life and its resistance to flank wear are observed at various cutting parameters such as cutting speed and feed rate by following the principle of design of experiments (DOE). It is inferred that AlCrN coated carbide tools perform nearly 70% better than the TiN coated carbide tools under high cutting speed and feed rate. AlCrN coating also enhances the durability of tool for metal cutting and thereby improves tool life even under harsh cutting conditions. A response surface methodology (RSM) is utilised to arrive at the optimum value for the various parameters which are responsible for improving the wear resistance and tool life. © 2012 W. S. Maney & Son Ltd. Source

Sakthivel S.,TCE QSTP LLC | Halder S.,Tata Consultancy Services Ltd. | Gupta P.D.,Tata Consultancy Services Ltd.
International Journal of Green Energy | Year: 2013

The aim of this research is to investigate the effects of residence time and reaction temperature on the yield of fatty acid methyl ester (biodiesel) with and without presence of biodiesel as a co-solvent. Experiments were performed for transesterification of non-edible oil (i.e., Jatropha curcas oil) in both batch and continuous mode. It is observed that presence of biodiesel as co-solvent enhances the yield appreciably with increase in reaction temperature and residence time. In addition, co-solvent enhances the miscibility between oil and methanol and consequently enhances the rate of reaction. Further, the results showed that the yield of fatty acid methyl esters obtained almost 20% higher than co-solvent free process. © 2013 Copyright Taylor and Francis Group, LLC. Source

Sakthivel S.,TCE QSTP LLC | Prasanna Venkatesh R.,Hanyang University
International Journal of Mining Science and Technology | Year: 2012

Many researchers in academia and industries are interested in reducing particle sizes from few sub-micrometers to nano-meter levels. These nano-particles find application in several areas including ceramics, paints, cosmetics, microelectronics, sensors, textiles and biomedical, etc. This article reviews the present state of the art for solid state synthesis of mineral nano-particles by wet milling, including their operating variables such as ball size, solid mass fraction and suspension stability. This article concludes and recommends with a critical discussion of nano-particles synthesis and a few common strategies to overcome stability issues. © 2012 Published by Elsevier B.V. on behalf of China University of Mining & Technology. Source

Discover hidden collaborations