Published: August 2013
Driven by increasing environmental and regulatory pressures and concerns over toxicity to humans, the global solvents market continues to undergo significant changes as a result of increasing demand for "greener" solvents in developed countries during the last fifteen years and declining demand for traditional solvents (outside of China).
Many large industrial users face switching from a hazardous compound to a more environmentally benign solvent that has a higher cost or that compromises product quality. The perfect solvent is not available, so manufacturers must make a trade-off between efficiency, cost and environmental impact. The opportunity to develop and market solvents with lower ecological and toxicological profiles is excellent, especially with the strong global "green" movement.
Global consumption of solvents is significant, with almost 28 million metric tons consumed in 2012.
The following pie chart shows world consumption of solvents by region:
Demand for solvents in China is expected to increase at an average annual rate of approximately 5–6% during the next few years, but demand is expected to remain flat or decrease in the United States and the European Union as a result of environmental regulations; the penetration of technologies that consume little, if any solvent; and greater solvent recovery and recycling. Another factor impacting demand is the transfer to China of industrial processes that consume large amounts of solvent, such as wood furniture coating and the assembly of shoes using solvent-borne adhesives.
Consumption in paints and coatings accounts for the largest share of the global solvent market at 40% of solvent use. Despite the trend during the last thirty years toward technologies that contain less solvent (e.g., powder coatings, high-solids and waterborne coatings), there is still significant use of solvents—nearly half of all coatings used are still solvent-based. However, this percentage will likely continue to decrease as more restrictive coatings regulations come into effect in the United States and the European Union during the next five years. In the United States, there is growing use of VOC-free solvents that have negligible contribution to lower atmospheric pollution.
Other uses for solvents include adhesives, inks, pharmaceuticals, chemical processing, metal and dry cleaning solutions, and agriculture.
Solvents are one of the most comprehensively regulated classes of chemicals, and tend to be regulated collectively as volatile organic compounds (VOCs), which contribute to lower-level ozone formation.
Both the United States and Europe have imposed stricter restrictions on solvents during the past twenty years, particularly with the European passage of the Registration, Evaluation and Authorization of Chemicals (REACH) legislation in 2007, which requires toxicity evaluations on thousands of substances. To comply with solvent-emission regulation, manufacturers have the option of installing engineering controls to limit emissions. In the dry cleaning industry, for example, emissions of perchloroethylene have been severely curtailed as users have installed specially designed cleaning and recycling equipment to decrease emissions by as much as 90%.
Solvents that are less hazardous to humans and the environment are part of the "green chemistry" movement, including supercritical CO2, which can be used for extraction. Other promising green solvents currently being researched but in limited use today are ionic liquids, which have essentially no vapor pressure, so there is no dissipation to the environment.
Several bio-based materials have been available for ten to fifteen years, and have enjoyed some commercial success in niche markets. The opportunity to develop and market solvents with lower ecological and toxicological profiles is excellent, especially with the strong global green movement, and increasing regulatory oversight of the solvents industry.