By Sarah Kennedy, PhD and Henry Nowicki, PhD
It is always necessary to be working on the right things. Green chemistry, a philosophy of sustainability, is a modern and necessary right thing. This article provides basic fundamentals on green chemistry and how it really helps corporate or small business management increase profits through streamlining business to better serve customers and protect the environment. We need to look at our business in a holistic way, then break it down into individual parts and work on improving those parts that provide the greatest economic benefits and customer satisfaction.
Green chemistry fundamentals
As natural resources are depleted and waste products accumulate, global citizens are becoming increasingly aware of environmental stewardship. For chemists and engineers, this requires the inspection of current manufacturing and research practices to discover improved alternatives that will lessen environmental impact and move us toward sustainability. US EPA first defined green chemistry (or sustainable chemistry) as “the design of chemical products and processes that reduce or eliminate the use or generation of hazardous substances. Green chemistry applies across the life cycle of a chemical product, including its design, manufacture, and use.” Green chemistry is not a new branch of chemistry; it is a new philosophy that can be used in all branches of chemistry. Paul Anastas and John Warner outlined 12 main principles of green chemistry in Green Chemistry: Theory and Practice.1 These principles guide chemists in creating an arsenal of metrics to evaluate chemical processes and develop green product/process alternatives. In many cases, green alternatives are less costly because the expense of waste removal can be greatly reduced.
Taken together, the green principles outline how each step of a chemical process should be evaluated for sustainability. The first two principles address reduction of waste through prevention and incorporation of all atoms of the starting material into the product, and number 10 suggests that a chemical product should be designed for innocuous degradation. Principles three through five stress the importance of reduced toxicity in the entire synthetic process. Conservation of energy and resources are addressed in Principles six through seven, while choosing the most effective reagents are addressed in eight and nine. Principle 11 suggests real-time monitoring can help control processes to maximize the other principles. Finally, Principle 12 caps the list by suggesting that all substances should be chosen to minimize risk of chemical accidents and damage to the environment. Numerous scientists and engineers have been able to positively add to the green chemist’s toolbox by developing green alternatives, and others have focused on developing metrics to help evaluate a product/ process for greenness.2
Contributing to the green toolbox, Philip Jessop of Queen’s University has written several peer-reviewed articles addressing the use of more benign solvent alternatives. In Searching for Green Solvents, Jessop created basicity versus polarity plots for traditional solvents and green solvents, and outlined methods to help choose the best green solvent for any given situation. Databases, such as the US National Library of Medicine’s TOXNET and US EPA’s ECOTOX and ToxCast, are resources that can be used to evaluate human and environmental toxicity, or forecast the probable toxicity of a new substance, respectively.
In his introductory text, Lancaster3 presents many process intensification engineering steps that can be implemented to improve the overall greenness of product production. These examples are merely a small portion of information available for chemists to evaluate their products and processes.
The ultimate evaluation for a product can be performed through a life-cycle assessment: a holistic examination of a product from cradle-to-grave. A proper life-cycle assessment includes evaluation of feedstocks, intermediates and desired products in manufacturing, distribution and use, calculation of all energy requirements and generation, as well as considering transportation and environmental emissions during the life cycle of the product. During life-cycle assessments, metrics such as atom economy, global warming potential, persistence and bioaccumulation can be performed on each substance involved in the synthetic process. While a life-cycle assessment takes a significant amount of research and time, the evaluation will help identify process steps that can be targeted for the greatest potential sustainability gain and lowering product cost. This is the most comprehensive route for a company to evaluate its product’s environmental impact.
To encourage green chemistry innovations, in 1996 the Presidential Green Chemistry Awards4 were developed. According to the US EPA awards brochure, during the period 1996-2011, the program presented 82 awards, which collectively eliminated more than 199 million pounds of hazardous chemicals and solvents, saved over 21 billion gallons of water, and eliminated 57 million pounds of carbon dioxide releases to air.
One 1996 awardee, S.C. Johnson, developed a company-wide tool called the GREENLIST ™ for classifying compounds used in their products by their environmental and health impacts. Several awards, including one to NovaSterilis Inc., demonstrated the creative use of benign solvents such as supercritical CO2 to replace toxic VOCs. Others focused on the use of new process engineering to improve energy efficiency.
Five awards are given each year and include categories for small businesses and academic laboratories. Reading through the Presidential award winners and journals such as Green Chemistry and Environmental Science and Technology shows the breadth of research being done in the field of green chemistry.
Improving teamwork to obtain goals
Ultimately, chemists, engineers and leadership must work together using green metrics and life-cycle assessments to achieve the goals of green chemistry. Developing green alternatives will most likely lead to long-term economic benefits, as well as positive public relations. Research in green chemistry is an expansive and fast-growing field, with tremendous impact on sustainability. Academia and industry can partner to become educated about green chemistry and develop creative solutions to implement the 12 principles. As new generations of chemists are trained for careers, teaching green chemistry concepts will help to ensure the development of benign, yet effective, chemistry to better protect human health and environmental quality of water and air. There are many opportunities to learn about green chemistry through the American Chemical Society5 and other trade organizations.6 Avail yourself of these resources and help lead us into a sustainable future.
This article provides fundamentals and homework to begin incorporation of green chemistry or a sustainable philosophy into your business. The goal is increased profits through improved day-to-day operations and satisfied customers. The next article in our planned series is targeted to activated carbon manufacture and the use of life-cycle assessment.7
- Anastas, P.T.; Warner, J.C. Green Chemistry: Theory and Practice. Oxford University Press: Oxford, 1998.
- Cann, M.C.; Connelly, M.E. Real World Cases in Green Chemistry. Ameri- can Chemical Society, 2001.
- Lancaster, M. Green Chemistry: An Introductory Text, 2nd ed. RSC Pub- lishing: Cambridge, 2010.
- EPA Office of Pollution Prevention and Toxics. Presidential Green Chemis- try Challenge Award Recipients 1996-2011. www.epa.gov/greenchemistry/ pubs/docs/award_recipients_1996_2011.pdf. (accessed June 8, 2012).
- ACS Green Chemistry Institute. http://portal.acs.org/portal/acs/ corg/content?_nfpb=true&_pageLabel=PP_TRANSITIONMAIN&node_ id=830&use_sec=false&sec_url_var=region1& uuid=5b47547f-1eaf- 45b8-b066-f3cbe6d234a5. (accessed June 8, 2012).
- Green Chemistry Network. www.greenchemistrynetwork.org/ (ac- cessed June 8, 2012).
- Henry Nowicki, Principal Investigator, FY2013 Environmental Protection Agency. Small Business Innovative Research proposal or SBIR, New Regeneration of Drinking Water Plants Used Granular Activated Carbons; page 27, April 29, 2012.
About the authors
Sarah A. Kennedy, PhD, is Professor of Chemistry at Westminster College and Director of the PACS course on green chemistry. Participants in the course learn basics of green chemistry and leave with a toolbox of metrics and examples to help guide their implementation of sustainable chemistry. Kennedy’s next PACS course is October 6 in Pittsburgh, PA. Course description is available www.pacslabs.com.
Henry Nowicki, PhD, MBA, is President and Senior Scientist for PACS and has been awarded SBIR R&D grants on activated carbon new product development. He teaches the introductory class for the Activated Carbon School. Questions, comments and suggestions for future green chemistry articles are welcomed. Phone (724) 457-6576 or email Henry@pacslabs.com.
About the company
Professional Analytical and Consulting Services Inc. (PACS) is a 29-year-old incorporated firm providing activated carbon laboratory testing services, R&D, consulting and a short-course program, which includes 59 different short courses for scientists and engineers. PACS provides a short course and consulting on green chemistry.