Biodiesel and green diesel generation: an overview

First, second, third, and fourth-generation biofuels are continuously evolving as a promising substitute to petrodiesel catalyzed by energy depletion, economic and environmental considerations. Bio-diesel can be synthesized from various biomass sources, which are commonly divided into FAME and renewable biodiesel. FAME biodiesel is generally produced by the transesterification of vegetable oils and fats while renewable diesel is produced by hydro-deoxygenation of vegetable and waste oils and fats. The different generation, processing technologies and standards for FAME and renewable biodiesel are reviewed. Finally, the life cycle analysis and production cost of conventional and renewable biodiesel are described.

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Recurring and Unresolved Problems in Sustainable Design

Volume 5: 25th International Conference on Design Theory and Methodology; ASME 2013 Power Transmission and Gearing Conference ◽

10.1115/detc2013-13459 ◽

2013 ◽

Cited By ~ 1

Author(s):

Bert Bras

Keyword(s):

Life Cycle ◽

Engineering Design ◽

Life Cycle Analysis ◽

Mechanical Engineering ◽

Sustainable Design ◽

Environmental Issues ◽

Design Methods ◽

The Past ◽

Environmental Considerations ◽

Made In

Much progress has been made in sustainable design over the past 20 years since the first publications on design for the environment started to appear in the mechanical engineering literature. Engineering design methods now attempt to include environmental considerations and Life-Cycle Analysis is a commonly used approach nowadays. Nevertheless, some fundamental problems seem to be recurring and remain unresolved. More so, some of these problems can have significant effects on the efficacy of design methods. Without consideration or even acknowledgement of these problems, proposed sustainable design methods may not bring us closer to sustainability at all. In this paper, we highlight a few of these recurring problems. Although true sustainable design should also include social and financial considerations, we will focus primarily on the environmental issues in this paper.

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Transition Metal Phosphides for the Catalytic Hydrodeoxygenation of Waste Oils into Green Diesel

Catalysts ◽

10.3390/catal9030293 ◽

2019 ◽

Vol 9 (3) ◽

pp. 293 ◽

Cited By ~ 16

Author(s):

M. Alvarez-Galvan ◽

Jose Campos-Martin ◽

Jose Fierro

Keyword(s):

Transition Metal ◽

Vegetable Oils ◽

Noble Metals ◽

Raw Materials ◽

Preparation Methods ◽

Green Diesel ◽

Waste Oils ◽

Metal Phosphides ◽

General Aspects ◽

Transition Metal Phosphides

Recently, catalysts based on transition metal phosphides (TMPs) have attracted increasing interest for their use in hydrodeoxygenation (HDO) processes destined to synthesize biofuels (green or renewable diesel) from waste vegetable oils and fats (known as hydrotreated vegetable oils (HVO)), or from bio-oils. This fossil-free diesel product is produced completely from renewable raw materials with exceptional quality. These efficient HDO catalysts present electronic properties similar to noble metals, are cost-efficient, and are more stable and resistant to the presence of water than other classical catalytic formulations used for hydrotreatment reactions based on transition metal sulfides, but they do not require the continuous supply of a sulfide source. TMPs develop a bifunctional character (metallic and acidic) and present tunable catalytic properties related to the metal type, phosphorous-metal ratio, support nature, texture properties, and so on. Here, the recent progress in TMP-based catalysts for HDO of waste oils is reviewed. First, the use of TMPs in catalysis is addressed; then, the general aspects of green diesel (from bio-oils or from waste vegetable oils and fats) production by HDO of nonedible oil compounds are presented; and, finally, we attempt to describe the main advances in the development of catalysts based on TMPs for HDO, with an emphasis on the influence of the nature of active phases and effects of phosphorous, promoters, and preparation methods on reactivity.

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Bioethanol Production: An Overview

10.5772/intechopen.94895 ◽

2020 ◽

Author(s):

Ifeanyichukwu Edeh

Keyword(s):

Life Cycle Assessment ◽

Life Cycle ◽

Driving Force ◽

Production Cost ◽

Economic Feasibility ◽

Fourth Generation ◽

Bioethanol Production ◽

Economic Analyses ◽

The Cost ◽

Very High

Bioethanol is currently being considered as a potential replacement for the conventional gasoline, especially as it possesses similar and some superior qualities enabling reduction in GHG and increases fuel reserve. Bioethanol used for commercial purposes is usually produced from edible feedstocks such as corn and sugar cane which increases the production cost. The high cost of these feedstocks is the driving force behind the search for the second, and third generations (3G) bioethanol produced from cheaper and available feedstocks. The fourth-generation bioethanol is being developed to further advance the 3G bioethanol to enhance the potential of algae to capture CO2 and to increase the production of specific compounds. Despite the efforts been made to reduce the cost of production through the use of diverse non-edible feedstocks, the cost of processing the feedstocks is still very high, thereby making bioethanol uncompetitive with the conventional gasoline. The life cycle assessment and techno-economic analyses are usually conducted to assess the economic feasibility and the environmental impact of the bioethanol production processes. This chapter thus, covers the State-of-the-art processes involved in bioethanol production including pretreatment, hydrolysis, fermentation processes, bioethanol recovery, integrated processes, Life cycle assessment, techno-economic analysis, exergy analysis and process simulation.

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