A. B. Chhetri

Bio: A. B. Chhetri is an academic researcher from Dalhousie University. The author has contributed to research in topics: Biodiesel & Biodiesel production. The author has an hindex of 3, co-authored 3 publications receiving 520 citations.

Waste Cooking Oil as an Alternate Feedstock for Biodiesel Production

Abstract: As crude oil price reach a new high, the need for developing alternate fuels has become acute. Alternate fuels should be economically attractive in order to compete with currently used fossil fuels. In this work, biodiesel (ethyl ester) was prepared from waste cooking oil collected from a local restaurant in Halifax, Nova Scotia, Canada. Ethyl alcohol with sodium hydroxide as a catalyst was used for the transesterification process. The fatty acid composition of the final biodiesel esters was determined by gas chromatography. The biodiesel was characterized by its physical and fuel properties including density, viscosity, acid value, flash point, cloud point, pour point, cetane index, water and sediment content, total and free glycerin content, diglycerides and monoglycerides, phosphorus content and sulfur content according to ASTM standards. The viscosity of the biodiesel ethyl ester was found to be 5.03 mm 2 /sec at 40 o C. The viscosity of waste cooking oil measured in room temperature (at 21° C) was 72 mm

Soapnut Extract as a Natural Surfactant for Enhanced Oil Recovery

Abstract: Primary and secondary recovery of oil from oil reservoirs contributes approximately 30% of the total oil in place in most oil reservoirs. Since the current economic development is heavily dependent on fossil fuel, increasing the amount of oil recovery is given considerable attention. One of the most widely used methods for enhanced oil recovery is the application of various types of surfactants in order to reduce the oil-water interfacial tension. However, the surfactants being used today are usually synthetic chemicals and polymers, which are expensive, linked to fossil fuels, and detrimental to the environment. In thisarticle, a natural surfactant prepared from the pericarp shell of fruit (Sapindus mukurossi) collected from a naturally available tree was used to reduce oil-water interfacial tension. The effect of surfactant concentration with 1%, 2%, 4%, 8%, and 12% was investigated. The effect of heat on interfacial tension was also studied. The experimental results showed that extract has a g...

Towards Producing a Truly Green Biodiesel

Abstract: The production of biodiesel has received considerable attention throughout the world in the past few years. As an alternative to petrodiesel, biodiesel is a renewable fuel that is derived from vegetable oils and animal fats. However, the existing biodiesel production process is neither completely “green” nor renewable because it utilizes fossil fuels, mainly natural gas as an input for methanol production. Also the catalysts currently in use are highly caustic and toxic. The purpose of this article is to propose a new concept that uses waste vegetable oil and non-edible plant oils as biodiesel feedstock and non-toxic, inexpensive, and natural catalysts that overcome the limitation of the existing process. The economic benefit of the proposed method is also discussed. The new concept will render the biodiesel production process truly green.

Qualities of transformative leaders in WASH: A study of gender-transformative leadership during the COVID-19 pandemic

Abstract: Introduction Equal access to water, sanitation and hygiene (WASH) for all requires leadership that prioritises and drives inclusion. Inclusive WASH also presents opportunities to advance equality more widely, with WASH a pathway to meaningful participation and empowerment for diverse groups. The concept of gender-transformative leadership-which connects ideas of leadership to transformative models of gender equality in development theory that challenge prevailing power structures-is a relevant lens for exploring inclusive WASH. This article shares findings and reflections from a positive deviance study that aimed to investigate gender-transformative leadership in the WASH sector to explore (i) the factors shaping gender-transformative leadership and the characteristics of gender-transformative leaders; (ii) actions taken by gender-transformative leaders; (iii) the types of outcomes achieved; and (iv) ways to strengthen gender-transformative leadership. Methods The study was undertaken during the COVID-19 pandemic and consisted of interviews with 19 leaders in Bhutan, Lao People's Democratic Republic, and Nepal. We developed a conceptual framework which considers leaders' (i) personal values and traits; (ii) leadership styles; (iii) actions; and (iv) outcomes, influenced by a range of (v) enabling factors and barriers. Results Leaders' personal values and traits included a strong learning orientation, social justice values, humility, courage, and altruism. Leadership styles were primarily empathetic, with leaders guided by a mission to lead by example and pursue equality in their professional and personal lives. Exploration of actions and outcomes revealed a range of inclusion-oriented WASH activities responding to pandemic-related challenges, with associated potential outcomes in shifting norms. However, validation of outcomes was not possible due to the study timeframe and complexity of tracing complex social change in a positive deviance study reliant on self-reporting. Analysis of enablers and barriers to gender-transformative leadership respectively emphasized the importance of educational opportunities and the persistence of traditional gender norms. Conclusion Findings contribute to the body of knowledge on gender-transformative leadership, being the first study to connect this concept to WASH. Future research could build further evidence by applying the conceptual framework to analyze additional contexts or sectors, and by more fully articulating and validating outcomes in terms of their potential for gender-transformative leadership to drive equality both in and beyond WASH.

Biodiesel production through the use of different sources and characterization of oils and their esters as the substitute of diesel: A review

Abstract: The world is confronted with the twin crises of fossil fuel depletion and environmental degradation. The indiscriminate extraction and consumption of fossil fuels have led to a reduction in petroleum reserves. Petroleum based fuels are obtained from limited reserves. These finite reserves are highly concentrated in certain region of the world. Therefore, those countries not having these resources are facing a foreign exchange crisis, mainly due to the import of crude petroleum oil. Hence it is necessary to look for alternative fuels, which can be produced from materials available within the country. Although vegetative oils can be fuel for diesel engines, but their high viscosities, low volatilities and poor cold flow properties have led to the investigation of its various derivatives. Among the different possible sources, fatty acid methyl esters, known as Biodiesel fuel derived from triglycerides (vegetable oil and animal fates) by transesterification with methanol, present the promising alternative substitute to diesel fuels and have received the most attention now a day. The main advantages of using Biodiesel are its renewability, better quality exhaust gas emission, its biodegradability and the organic carbon present in it is photosynthetic in origin. It does not contribute to a rise in the level of carbon dioxide in the atmosphere and consequently to the green house effect. This paper reviews the source of production and characterization of vegetable oils and their methyl ester as the substitute of the petroleum fuel and future possibilities of Biodiesel production.