The ReSolve project aimed to replace two hazardous solvents, currently used in large volumes within European industries, with safer alternatives derivable from non-food carbohydrates. There is an urgent need to replace these solvents due to their health and environmental impacts, which has resulted in increasing regulation of their use across the globe. The new, safer solvents developed in ReSolve have a wide range of applications and the project aimed to demonstrate their sustainability, low impact on health and high performance. The research will affect thousands of downstream businesses and consumers, who use the products made using the traditional solvents. ReSolve will have a far wider impact than on replacing these two solvents alone – the substitution methodology developed can be applied to a large number of important but problematic solvents. The reduction in health impact of replacement of such solvents is vital to the millions of European citizens that are routinely exposed to solvents as part of their job or in domestic applications.
The solvents that the project aimed to replace were NMP (N-methyl-2-pyrrolidone) and toluene. NMP is currently used in the production of cleaning products, paint removers, pharmaceuticals and inks among other important commercial products. It is used in the electronics, pharmaceutical, industrial (and household) cleaning and agrochemical industries. It is used by consumers as well as by professional workers. However, it is easily absorbed through the skin and it may damage fertility or the unborn child. Therefore, it has been identified as a Substance of Very High Concern (SVHC) under the EU’s flagship chemicals legislation REACH. Toluene, used in the production of products like adhesives, paints/coatings and plastics is easily inhaled. It is suspected to cause damage to the unborn child, may cause damage to the central nervous system and it is not allowed (<0.1% by weight) in adhesives and spray paints intended for sale to the public.
The main objectives were achieved:
• Produce at least two new carbohydrate-based solvents to replace toluene or NMP in specific applications.
Two key candidates, one each to replace toluene and NMP, were produced and tested. 2,2,5,5-tetramethyloxolane (TMO) was found to be widely applicable in replacing toluene while CyreneTM showed utility in replacing NMP in several applications. Several other candidates were found useful in replacing NMP in some applications.
• Produce the two new solvents at a suitable volume to allow testing of the solvents in a relevant industrial application.
Two key candidates were produced at pilot-scale and tested at an industrial setting within the project and by numerous external parties.
• Establish a new, cost-effective testing strategy to allow the rapid evaluation of the toxicological safety of any potential new solvents.
A new testing strategy combining in vitro and in silico methods was developed and used to analyse 129 samples, including current solvents, replacement candidates and starting materials.
• Evaluate how the new solvents would perform in environmental and economic terms, including market uptake and costs/methods of large-scale production.
Economic and environmental assessments were completed, allowing candidates to be benchmarked. A market study was delivered and a production demo plant for two candidates was designed.
