The ideal E factor is 0 and higher E factors are relatively less desirable. E factors that can be tolerated depend upon the value of the product and the amount of product produced. For bulk chemicals manufactured in amounts of hundreds of thousands to millions of tons per year, tolerable E factors typically range from 1 to 5. In the fine chemical and specialty chemical industry where annual quantities are typically measured as a few thousand tons per year E factors up to around may be acceptable if the value of the product is high enough to justify the cost of treating and disposal of wastes.
In the pharmaceutical manufacturing industry where annual quantities generated typically are measured in tens to several hundred tons per year, acceptable E factors may be up to about Download a printable version with answers to tasks here Back to top of page This work is licensed under a Creative Commons Attribution 4. Share this: Twitter Facebook.
Like this: Like Loading Follow Following. Sign me up. The global impact, over the last 25 years, of the principles of green chemistry and sustainability, and the pivotal role of the E factor concept in driving resource efficiency and waste minimisation, in the chemical and allied industries, is reviewed.
Following an introduction to the origins of green chemistry and the E factor concept, the various metrics for measuring greenness are discussed. It is emphasised that mass-based metrics such as atom economy, E factors and process mass intensity PMI need to be supplemented by metrics, in particular life cycle assessment, which measure the environmental impact of waste and, in order to assess sustainability, by metrics which measure economic viability.
The role of catalysis in waste minimisation is discussed and illustrated with examples of green catalytic processes such as aerobic oxidations of alcohols, catalytic C—C bond formation and olefin metathesis. Solvent losses are a major source of waste in the pharmaceutical and fine chemical industries and solvent reduction and replacement strategies, including the possible use of neoteric solvents, such as ionic liquids and deep eutectic solvents, are reviewed. Biocatalysis has many benefits in the context of green and sustainable chemistry and this is illustrated with recent examples in the synthesis of active pharmaceutical ingredients.
The importance of the transition from an unsustainable economy based on fossil resources to a sustainable bio-based economy is delineated, as part of the overarching transition from an unsustainable linear economy to a truly green and sustainable circular economy based on resource efficiency and waste minimisation by design.
Sheldon, Green Chem. To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page. If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given. You can always adapt the E-Factor equation to get more specific information about your processes or types of emissions.
For example, if you only want to measure your efficiency in terms of air emissions maybe you primarily deal with air permitting , just include only kilograms of air emissions in the E-Factor equation.
This also applies to specific facilities, processes, or even personnel: you can adapt the E-Factor equation to measure the efficiency of just about anything or anyone that plays a role in your business.
Try adding E-Factors to your employee performance evaluations by comparing the amount of product that gets lost as emissions, spilled, or wasted against how much ends up in the final product.
Part of getting sustainable is constantly making better choices the materials you use in an effort to reduce your waste generation and environmental impact. First, calculate your E-Factor for a period of time before any changes have been made. Next, calculate your E-Factor for the exact same length of time after the change was made, making sure to use all the same data sources as before. You can drill down even more and perform multiple E-Factor calculations using different sources or adjust your time periods if you need to get more specific data.
Imagine how your performance could affect others further down the supply chain. Do you think companies you supply would like to know how much waste was associated with the manufacture of your product?
0コメント