“Green Chemistry” A greener future… Prof. Ángela González Department of Biology, Chemistry and Env. Sciences Interamerican University of Puerto Rico San Germán Campus agonzal@sg.inter.edu Angela González -UIA San Germán

What to expect from this talk… Why? History What? Definitions How? Principles Examples Angela González, Ph.D. / UIA-SG Angela González -UIA San Germán

Remediation Techniques ¿WHY? 70’s – need to improve environmental quality Control  Laws Contaminants produced and THEN treated before releasing them to the environment Excellent idea IF there is good control and handling of environmental laws It is continuous, slow and expensive Remediation Techniques Angela González, Ph.D. / UIA-SG Angela González -UIA San Germán

Angela González -UIA San Germán Angela González, Ph.D. / UIA-SG Angela González -UIA San Germán

¿WHY? 1991 – Green Chemistry is promoted by EPA – (Paul Anastas) Prevention!!!! Angela González, Ph.D. / UIA-SG Angela González -UIA San Germán

What is Green Chemistry? … or sustainable/environmentally benign chemistry is the design of chemical products and processes that reduce or eliminate the use and generation of hazardous substances www.epa.gov/greenchemistry Angela González, Ph.D. / UIA-SG Angela González -UIA San Germán

What is Green Chemistry? … principles to reduce or eliminate use or production of dangerous chemicals in the design, manufacture and application of chemical products. Green Chemistry Theory & Practice, P T Anastas & J C Warner, Oxford University Press 1998 Angela González, Ph.D. / UIA-SG Angela González -UIA San Germán

Green Chemistry Goals Reduction or elimination of Waste Toxic chemicals or processes Energy use Angela González, Ph.D. / UIA-SG

Green chemistry is looking to: Waste Materials Danger Risk Energy Environmental Impact COST! ($$$$) Reduce Angela González, Ph.D. / UIA-SG Angela González -UIA San Germán

Green Chemistry vs. Environmental Chemistry Study of sources, reactions, transport, effects and destruction of chemical compounds in the ground, water and air. Stanley Manahan, Env. Chemistry, 6th Ed. CRC Press. 2005 Angela González, Ph.D. / UIA-SG Angela González -UIA San Germán

Green Chemistry Environmental Regulations Clean up Research Monitoring Prevention Green Chemistry Angela González, Ph.D. / UIA-SG Angela González -UIA San Germán

Green Chemistry Benefits: Reduced waste, eliminating costly end-of-the-pipe treatments Safer products Reduced use of energy and resources Improved competitiveness of chemical manufacturers and their customers Angela González, Ph.D. / UIA-SG www.epa.gov/greenchemistry/ Angela González -UIA San Germán

What has happened? 1996 Presidential Green Chemistry Challenge Awards -promote non contaminant technologies. 1997 Green Chemistry and Engineering Conference 1999 Journal “Green Chemistry” Chemical and Engineering News 2000 GCI integrated into ACS 2000 Journal of Chemical Education Angela González, Ph.D. / UIA-SG Angela González -UIA San Germán

and? 1.2 billions 57 millions 16 billions Until 2006 all the technologies nominated to the PGCCA had eliminated the use or production of: 1.2 billion pounds of chemicals and solvents per year Enough to fill 5000 train tanks or a 62 miles long train 57 million pounds of CO2 has been reduced equivalent to take out circulation 37000 cars. 16 billion gallons of water per year have been saved 1.2 billions 57 millions 16 billions Angela González, Ph.D. / UIA-SG www.epa.gov/greenchemistry/ Angela González -UIA San Germán

Twelve Principles of Green Chemistry Paul Anastas and John Warner in Green Chemistry: Theory and Practice (Oxford University Press: New York, 1998). Angela González -UIA San Germán

Twelve Principles of Green Chemistry: 1. Prevent waste Design chemical syntheses to prevent waste, leaving no waste to treat or clean up. Easier than clean up, transport or store them Transforming chemical reactions that incorporate the largest amount of the starting materials = Less waste! Angela González, Ph.D. / UIA-SG Angela González -UIA San Germán

¿What kind of industry is worst? Products (tons) Kg byproducts/ Kg products Petroleum Refinery 106 – 108 <0.1 Chemical Production 104 – 106 1-5 Specialized Chemical Compounds 102 - 104 5 – 50 Pharmaceutical 10 - 103 25 – 100+ Petróleo es la más limpia!!!!... Tiene que ser, ya que los márgenes de ganancia por Kg. son pequeños New Industries: Large gain margins $$$ More complex chemistry More waste production Angela González, Ph.D. / UIA-SG R A Sheldon J Chem Tech Biotechnol 1997 68 381 Angela González -UIA San Germán

Possible sources of waste reduction: Inputs “eco-friendly” solvents, high purity reagents, solvent recycling. Production Optimization of reaction time, temperature and pressure. New synthesis pathways. Discharges Reduce water usage, improve filtering procedures and reuse waste products. Angela González, Ph.D. / UIA-SG Angela González -UIA San Germán

Twelve Principles of Green Chemistry: 2 Twelve Principles of Green Chemistry: 2. Design safer chemicals and products: Design chemical products to be fully effective, yet have little or no toxicity. …chemicals that are less hazardous to human health and the environment are: Less toxic to organisms and ecosystems Not persistent or bioaccumulative in organisms or the environment Inherently safer with respect to handling and use Angela González, Ph.D. / UIA-SG Angela González -UIA San Germán

Avoid reactions that give dangerous by- products Twelve Principles of Green Chemistry: 3. Design less hazardous chemical syntheses: Use and generate substances with little or no toxicity to humans and the environment. Avoid reactions that give dangerous by- products Angela González, Ph.D. / UIA-SG Angela González -UIA San Germán

Twelve Principles of Green Chemistry: 4. Use renewable feedstocks: Use raw materials and feedstocks that are renewable rather than depleting. Agricultural products Wastes of other processes; Reduce dependency from fossil fuels (petroleum, natural gas, or coal) or are mined. Ejemplo byproduct de fermentacion el CO2 se vende a las companias que envasan refrescos Angela González, Ph.D. / UIA-SG Angela González -UIA San Germán

Catalysts are used in small amounts Twelve Principles of Green Chemistry: 5. Use catalysts, not stoichiometric reagents: They are selective Catalysts are used in small amounts Can carry out a single reaction many times. Improve production and energy consumption They are preferable to stoichiometric reagents, which are used in excess and work only once. Angela González, Ph.D. / UIA-SG Angela González -UIA San Germán

Twelve Principles of Green Chemistry: 6. Avoid chemical derivatives: blocking or protecting groups or any temporary modifications if possible. Derivatives use additional reagents and generate waste. Angela González, Ph.D. / UIA-SG Angela González -UIA San Germán

Twelve Principles of Green Chemistry: 7. Maximize atom economy: Final product contains the maximum proportion of the starting materials. There should be few, if any, wasted atoms. Relation between atoms in the products and atoms in the reagents Addition – good atom efficiency Elimination – not so good… Angela González, Ph.D. / UIA-SG Angela González -UIA San Germán

“Because an Atom is a Terrible Thing to Waste” Atom Economy Barry Trost, Stanford University Evaluate the efficiency of the chemical transformation “Because an Atom is a Terrible Thing to Waste” Angela González, Ph.D. / UIA-SG Angela González -UIA San Germán

Atom Economy How many of the atoms of the reactant are incorporated into the final product and how many are wasted? Angela González, Ph.D. / UIA-SG Angela González -UIA San Germán

How a reactions efficiency is measured? Reaction Yield % yield = (actual quantity of products achieved) x 100 (theoretical quantity of products achievable) Atom Economy* % atom economy = (MWt of desired products) x 100 (MWt of all products) Rendimiento: Cálculo que históricamente se ha utilizado para evaluar eficiencia No provee información sobre productos colaterales o desechos formados en la reacción Economía atómica: Considera el grado en que TODOS los reactantes son incorporados en el producto deseado Angela González, Ph.D. / UIA-SG * B M Trost, Science 1991, 254, 1471 Angela González -UIA San Germán

% Atom Economy = (FW of atoms utilized/FW of all reactants) X 100 = H3C-CH2-CH2-CH2-OH + Na-Br + H2SO4  H3C-CH2-CH2-CH2-Br + NaHSO4 + H2O 1 2 3 4 5 6 Reagents Formula Reagents FW Utilized Atoms Weight of Unutilized Weight of H3C-CH2-CH2-CH2-OH 74 4C, 9H 57 OH 17 Na-Br 103 Br 80 Na 23 H2SO4 98 ------ 2H, 4O, S Total 4C, 12H, 5O, Br, Na, S 275 4C, 9H, Br 137 3H, 5O, Na, S 138 % Atom Economy = (FW of atoms utilized/FW of all reactants) X 100 = (137/275) X 100 = 50% Angela González, Ph.D. / UIA-SG Angela González -UIA San Germán

% Yield vs. atomic economy Angela González, Ph.D. / UIA-SG Angela González -UIA San Germán

Chemical Reactions and Atomic Economy Addition > Substitutions > Eliminations Re-arrangements: 100 % efficient Ex: Diels-Alder Angela González, Ph.D. / UIA-SG Angela González -UIA San Germán

USE: innocuous chemicals. Twelve Principles of Green Chemistry: 8. Use safer solvents and reaction conditions Avoid: solvents, separation agents, other auxiliary chemicals. USE: innocuous chemicals. Angela González, Ph.D. / UIA-SG Angela González -UIA San Germán

Solvents Organic solvents = high VOC’s Alternatives Synthesis without solvents Water Supercritical fluids (CO2) Ionic Liquids Uso de solventes orgánicos es lo más común Angela González, Ph.D. / UIA-SG Angela González -UIA San Germán

Dry Cleaning – Greener… Initially gasoline and kerosene were used Now use PERC Future use Supercritical CO2 and CO2 surfactants Using CO2 eliminates hazardous waste generation of perc. CO2 does not pose the environmental and human health risks associated with perc (used by 34,000 dry cleaners in US). Using CO2 reduces environmental regulatory burdens for Hangers operators. Uses waste CO2 from other processes. Angela González, Ph.D. / UIA-SG Angela González -UIA San Germán

Twelve Principles of Green Chemistry: 9. Increase energy efficiency: Run chemical reactions at ambient temperature and pressure whenever possible. Angela González, Ph.D. / UIA-SG Angela González -UIA San Germán

Twelve Principles of Green Chemistry: 10 Twelve Principles of Green Chemistry: 10. Design chemicals and products to degrade after use: Design chemical products to break down to innocuous substances after use so that they do not accumulate in the environment. EJEMPLO DE LAS BOLSAS DE PAPEL QUE USSAN EN ESPANA Y QUE SON FOTODEGRADABLES Angela González, Ph.D. / UIA-SG Angela González -UIA San Germán

Twelve Principles of Green Chemistry: 11 Twelve Principles of Green Chemistry: 11. Analyze in real time to prevent pollution: Include in-process real- time monitoring and control during syntheses to minimize or eliminate the formation of byproducts. Angela González, Ph.D. / UIA-SG Angela González -UIA San Germán

PAT: Process Analytical Technologies Measure quality and execution properties DURING manufacturing Information is gather continuously to improve process Diseñando, analizando y controlando fabricación Se miden atributos de calidad y ejecución durante el proceso de fabricación Se determinan características de los materiales de partida y de los compuestos formados a lo largo de la producción. Angela González, Ph.D. / UIA-SG http://www.fda.gov/Cder/OPS/PAT.htm Angela González -UIA San Germán

Pre - PAT Analysis of raw materials, intermediates and final products In case of problems: WHOLE lot rejected = A LOT OF WASTE!... A LOT OF $$$$!! Tiempo entre toma de muestras y análisis de las mismas, impedía hacer correcciones en condiciones del proceso Angela González, Ph.D. / UIA-SG Angela González -UIA San Germán

Like you do while cooking… While you cook you test the food, and apply the needed corrections to improve it: If it is too salty: … If it is too bland: …. If you have extra guest… If it is too acidic: stop there… Al cocinar usted: Prepara los ingredientes (materia prima) Huele la carne Si huele raro – esta mala Si no, procede… Prepara resto ingredientes Cebolla tiene hongos – usar otra Monta el sancocho… A medida que se va cocinando UD: Prueba por sal Si falta sal… Si tiene de sobra… Chequea que se cocine la carne Si las papas ya se cocieron y la carne no: Saca las papas para que no se deshagan… Angela González, Ph.D. / UIA-SG Angela González -UIA San Germán

PAT: Process Analytical Technologies Helps to: Understand the process Make corrections in the moment, without waiting for the final product Develop mitigation strategies. Inlcuye análisis: Físico Químico, Matemático Microbiológico De Riesgo Diseño y desarrollo de procesos que pueden asegurar consistencia en la calidad del producto. Reduciendo tiempos de produccion al utilizar mediciones “en-linea”, “fuera de la linea” o “dentro de la linea” de producción Previene rechazo de productos, producción de productos colaterales y re-procesamiento Aumenta automatización – mejorando seguridad del operador y reduciendo error humano Angela González, Ph.D. / UIA-SG Angela González -UIA San Germán

Twelve Principles of Green Chemistry: 12 Twelve Principles of Green Chemistry: 12. Minimize the potential for accidents: Design chemicals and their forms (solid, liquid, or gas) to minimize the potential for chemical accidents: explosions, fires, and releases to the environment. Angela González, Ph.D. / UIA-SG Angela González -UIA San Germán

Example of Green Chemistry Synthesis - Ibuprofen Angela González -UIA San Germán

Ibuprofen Synthesis Classic Route Demand: 13,000 TPY Developed in 1960 6 steps reaction reaction:6 pasos con reactivos diferentes en cantidades estequiométricas Angela González, Ph.D. / UIA-SG Angela González -UIA San Germán

Ibuprofen Synthesis Classic Route Atomic Economy: 32% If this synthesis were to be used today, the amount of by-products per year: 27,000 TPY Angela González, Ph.D. / UIA-SG MORE WASTE THAN PRODUCT!!! Angela González -UIA San Germán

Boots & Hoechst Synthesis of Ibuprofen – Green Route Developed to improve production: * 3 steps * No solvents * Catalytic vs. stoichiometric reagents * Recycling, reuse and recovery of byproducts and reagents (acetic acid >99%; HF >99.9%) Angela González, Ph.D. / UIA-SG Angela González -UIA San Germán

Atomic Economy 77% Faster More % yield Less waste produced $$$$$$ Boots & Hoechst Synthesis of Ibuprofen – Green Route Atomic Economy 77% Faster More % yield Less waste produced $$$$$$ Angela González, Ph.D. / UIA-SG And a happier environment Angela González -UIA San Germán

Angela González -UIA San Germán Angela González, Ph.D. / UIA-SG Angela González -UIA San Germán

Angela González -UIA San Germán Angela González, Ph.D. / UIA-SG Angela González -UIA San Germán

What is green chemistry looking for? Waste production minimization from the source Use of catalysts Use of non-toxic reagents Use of renewable sources Improvement of atomic economy Use of non-solvent or environmental benign solvents Angela González, Ph.D. / UIA-SG Angela González -UIA San Germán

ACS Green Chemistry Institute: Anastas, P. T.; Warner, J. C. Green Chemistry: Theory and Practice; Oxford University Press: New York, 1998 B M Trost, Science 1991, 254, 1471 PAT: http://www.fda.gov/Cder/OPS/PAT.htm EPA: http://www.epa.gov/greenchemistry/index.html ACS Green Chemistry Institute: http://acs.org Michael Cann, University of Scranton: http://academic.scranton.edu/faculty/CANNM1/greenchemistry.html Angela González, Ph.D. / UIA-SG Angela González -UIA San Germán