key: cord-0705504-g3ie35bk authors: Cohen, Gabriel; Kreutzer, Nathan; Mowat, Katie; Hassan, Ashraf Aly; Dvorak, Bruce title: Compliance with hand sanitizer quality during the SARS-CoV-2 pandemic: Assessing the impurities in an ethanol plant date: 2021-07-21 journal: J Environ Manage DOI: 10.1016/j.jenvman.2021.113329 sha: 5f2c6c96cb939c118b13d7fc74d8bc19943e324b doc_id: 705504 cord_uid: g3ie35bk Using alcohol-based disinfectants is an effective method for preventing the spread of COVID-19. However, non-traditional manufacturers of alcohol-based disinfectants, such as ethanol plants, need to undergo additional treatment to curb their impurities to limits set by the Food and Drug Association (FDA) to produce alcohol-based disinfectants. To transform them to disinfectant-grade alcohol, 17 process streams in a dry-mill ethanol plant were analyzed to determine the quality parameters for acetaldehyde, acetal, propanol, methanol, and water, including chemical oxygen demand, total suspended solids, and nutrients. Results suggest that the process stream generated by the distillation column requires further treatment because the acetaldehyde and acetal concentrations are significantly higher than the impurity limit set by the FDA. The addition of a second distillation column could be a potential method for addressing impurities and it will have minimal influence on hazardous air pollutant generation and water use. ethanol plants, need to undergo additional treatment to curb their impurities to limits set by 23 the Food and Drug Association (FDA) to produce alcohol-based disinfectants. To transform 24 them to disinfectant-grade alcohol, 17 process streams in a dry-mill ethanol plant were 25 analyzed to determine the quality parameters for acetaldehyde, acetal, propanol, methanol, 26 and water, including chemical oxygen demand, total suspended solids, and nutrients. Results 27 suggest that the process stream generated by the distillation column requires further treatment 28 because the acetaldehyde and acetal concentrations are significantly higher than the impurity 29 limit set by the FDA. The addition of a second distillation column could be a potential 30 method for addressing impurities and it will have minimal influence on hazardous air 31 pollutant generation and water use. 32 The COVID-19 pandemic has affected nearly every country across the globe. Disinfection of 48 hands and surfaces can help prevent its spread. Alcohol-based sanitizers have become a 49 standard for disinfecting frequently touched surfaces. They serve as a substitute when soap 50 and water are not readily available (Bloomfield, 2007) . Alcohol-based sanitizers are 90%-51 99.9% effective depending on the target pathogen (Tuladhar, 2015) . Disinfection products 52 were in high demand at the start of the pandemic (March 2020), and suppliers were struggling 53 to keep up owing to a lack of raw materials. Demand for alcohol-based disinfectants are still 54 high to this day and the market for disinfectants is growing exponentially across the globe 55 (Research Dive, 2021) . 56 The Food and Drug Association (FDA) has strict limits on impurity concentrations in hand 58 sanitizers but has temporarily raised said limits and associated regulations to allow 59 nontraditional manufacturers to enter the market and meet the growing demand (FDA, 2020). 60 The interim standards were instituted on January 31, 2020, with the declaration of a public 61 health emergency by the Secretary of Health and Human Services (HHS). These interim 62 standards will cease and revert to the traditional standards once the public health emergency 63 is over. Interim and normal impurity limits are listed in Table S1. 64 65 Ethanol plants, a nontraditional manufacturer of alcohol-based disinfectants, began producing 66 alcohol-based disinfectants during the COVID-19 pandemic (Voegele, 2020) . This is because 67 as the demand for alcohol-based disinfectants increased as the demand for ethanol fuel has 68 decreased. Some US ethanol plants restructured to provide ethanol production for hand 69 sanitizers (Kelly, 2020; Reed, 2020) . The World Health Organization has two formulations of 70 J o u r n a l P r e -p r o o f alcohol based disinfectants with an active ingredient of either isopropyl alcohol or ethanol the 71 latter in which is produced by ethanol plants (World Health Organization, 2009). 72 The production of ethanol from corn starch biomass is a multistep process. The process 74 begins with the cleaning, grinding, liquefaction, and saccharification of corn starch to turn it 75 into a fermentable mash. Dry mill ethanol plants use corn as the raw material for production. 76 Once the corn is converted into mash, the corn will go through the fermentation process 77 where yeast is added. The fermentation process produces beer containing 10% alcohol which 78 is sent to a distillation tower to separate the alcohol from the solids and water where they will 79 be treated and disposed of (Eidman, 2007) . Impurities generated from the fermentation of 80 corn starch include esters, organic acids, and higher alcohols (Onuki, 2008) The final product 81 produced by distillation contains 95% alcohol and 5% water. In addition to meeting emission standards set by NESHAP, many ethanol facilities are 105 seeking methods to reduce their GHG footprint to increase their market share and 106 profitability. An example of this trend is California's low-carbon fuel standard (LCFS) 107 carbon credit system, which incentivizes creating low-carbon intensity fuels (California Air 108 Resources Board, 2020). US ethanol producers can generate credits, which can be exchanged 109 processes. These data may be helpful in identifying possible streams that could be used as an 121 input to innovative waste treatment processes developed for the ethanol industry, such as bio-122 scrubbers for air emissions (Duerschner, 2020) . This study examines data from one dry-mill 123 ethanol plant (hereafter referred to as the plant), and although operations in other facilities 124 will not be the same, it is believed that the general concentration and mass flow rates for the 125 impurities will be similar to other dry-mill ethanol plants. Table 1 . Fig. 2(A) presents the flow throughout the 194 plant in terms of the impurity concentration and flow rate of the liquid samples. Fig. 2 NS NS = no solids in the process stream and