No full-text available
To read the full-text of this research,
you can request a copy directly from the authors.
Formulation, Performance and Sustainability Aspects of Liquid Laundry Detergents
Abstract
In this study, we have investigated the development of liquid laundry detergent formulations over the past 10 years with regard to performance and sustainability profiles. We found that between 2001 and 2011, wash performance has significantly increased while at the same time the surfactant level was substantially reduced, leading to lower Global Warming Potential and improvements in all other relevant lifecycle indicators. One driver is the partial replacement of surfactants with other, more effective ingredients like enzymes that allow for additional performance dimensions and new consumer-relevant benefits. Future surfactant systems that help increase and support the stability and functionality of enzymes will further boost performance at low temperature, improve storage stability and enable more concentrated formulations at competitive costs.
... Over the years, manufacturers of washing machines have substantially reduced water and energy usage by at least 50 % [12][13][14]. Detergent manufacturers also have made significant progress in reducing their environmental impact with the introduction of enzymes which have allowed for lower wash temperatures and simultaneously improved cleaning performance [15]. Additionally, the move to compact detergent forms provided significant benefits for a range of environmental factors [7]. ...
... At the beginning of the intervention phase, subjects were given either the EBD or HDD in blinded containers ( Figure 2) to use and be monitored for 8 weeks (weeks 5-12). After the intervention phase there was a post-test cool down period where subjects returned to their usual product (weeks [13][14][15][16][17][18]. After this cooldown, post-test qualitative interviews were conducted with select subjects. ...
The laundry process is energy-intensive and an important target for reducing residential environmental impacts. Category life-cycle analysis (LCA) studies show the primary environmental impact is due to the energy consumed during the use phase, mainly for heating water. However, doing the laundry is a complex socio-technical system, where addressing sustainability requires not only technical levers but also an understanding of users’ habits, practices, and belief systems. This study investigates if and how consumers change their laundry habits and product satisfaction when using a technically lower-performing eco-brand detergent compared to a heavy duty high-performance detergent. These represent two distinct sustainable innovation strategies within the detergent industry, i) high-performance detergents formulated to provide excellent cleaning performance at lower wash temperatures and ii) eco-brand detergents optimized for a lower ingredient footprint but reducing cleaning performance. It is hypothesized that consumers may compensate in ways detrimental to the overall sustainability of the laundry lifecycle. The results showed significantly lower consumer satisfaction with the eco-brand performance which led to compensatory behavior including increased detergent dosing and higher wash temperatures. This study confirms the importance of detergent cleaning performance for sustainable consumer habit changes regarding lower wash temperatures.
... In early work on the conventional surfactant formulations for cold-water detergency, Matson and Cox [25,26] found that temperature and water hardness were major factors on detergency performance, foam characteristics, and cost. Although there are many studies on optimizing the laundry detergent formulations for different conditions, especially at moderate temperatures [27,28], there is limited research on the detergency below 30°C. Recently, microemulsions using mixed surfactant systems of a linear C 10 -18PO-2EO-NaSO 4 extended surfactant and a hydrophobic twin-tailed sodium dioctyl sulfosuccinate surfactant (SDOSS) were examined for cold water detergency of vegetable oils and semi-solid fats (canola, jojoba, coconut, and palm kernel oils) by Do et al. [23]. ...
Triglycerides and vegetable oils are amongst the most difficult oils to remove from fabrics due to their highly hydrophobic nature; this is all the more challenging as cold water detergency is pursued in the interest of energy efficiency. Recently, extended surfactants have produced very encouraging detergency performance at ambient temperature, especially at low surfactant concentration. However, the salinity requirement for extended surfactants was excessive (4–14%) and there is limited research on extended-surfactant-based microemulsions for cold water detergency (below 25 °C). Therefore, extended-surfactant-based microemulsions are introduced in this study for cold temperature detergency of vegetable oils with promising salinity and surfactant concentration. The overall goal of this study is to explore the optimized microemulsion formulations with low surfactant and salt concentration using extended surfactant for canola oil detergency at both 25 and 10 °C. It was found that microemulsion systems achieved good performances (higher than those of commercial detergents) corresponding to IFT value 0.1–1 mN/m with the surfactant concentration as low as 10 ppm and 4% NaCl at 25 °C, and as low as 250 ppm and 0.1% (1000 ppm) NaCl at 10 °C. In addition, microemulsion systems were investigated with a different salt (CaCl2, or water hardness, versus NaCl) at 10 °C, demonstrating that 0.025% CaCl2 (250 ppm) can produce good detergency; this is in the hardness range of natural water. These results provide qualitative guidance for microemulsion formulations of vegetable oil detergency and for future design of energy-efficient microemulsion systems.
... Mannanases and pectinases help in the removal of stains containing natural thickening agents, while lipases enhance the removal of triglycerides containing stains [6 -8]. The use of cleaning enzymes in laundry detergents leads to a much better performance than the surfactant system alone [9,10]. ...
Enzymes and surfactants are both essential ingredients that determine the performance of modern laundry detergents. We have conducted an investigation of the interaction of surfactants and enzymes under laundry detergent application conditions in order to understand the influence of individual ingredients and to optimize detergent performance. We can show that for a given protease enzyme, individual surfactants in a constant detergent matrix have a significant impact on relevant stability and performance parameter. While certain anionic surfactants like e. g. linear alkylbenzene sulfonate show strong protease inactivation, nonionic surfactants did only show slight inactivation over time. On the other hand, proteolytic performance of protease on test stains was most driven by fatty alcohol ether sulfate. Knowledge about the impact of individual surfactants on proteases will enable the best choice of ingredients for mixed surfactant systems with optimized enzyme performance and stability.
Enzymes in laundry detergents and household cleaners make a significant contribution to enhancing the performance and improving the environmental properties of laundry detergents and household cleaners. They are also essential for differentiating premium brands in relation to standard and “value-for-money” products. Proteases, amylases, cellulases, lipases, mannanases, and pectate lyases are used in detergents. In automatic dishwashing detergents, it is proteases and amylases. In this chapter, performance characteristics of the enzymes and the typical requirements of the different enzyme classes for these products are discussed. The benefits of enzyme technology to the sustainability of washing are assessed, as are aspects of health, safety, and environmental relevance. The economic importance is touched upon and an outlook on the expected future is attempted.
New detergents approach such as pre-dosed liquid and powder as pre-treatment to enhance cleaning efficiency has received great interest among consumer and is becoming a trend in laundry industry. Formulation of detergents is continuously developed to improve cleaning efficiency and to adapt and fulfill market demands. In this study, three liquid stain remover formulations containing thermostable alkaline protease 50a as additive were developed. The developed stain remover formulations were specifically designed to remove proteinaceous stains on fabrics. Azo-casein assay was performed to evaluate the stability of the thermostable alkaline protease 50a in each formulation. Wash performance analysis was also carried out to determine the stain removal efficiency of the developed formulations on selected fabrics namely satin, crepe and koshibo. The results obtained shows that the thermostable alkaline protease 50a lost more than 89% of its activity after one week of incubation in these three formulations. The developed stain remover formulation exhibited good stain removal efficiency (84.8-96.46%) in comparison to tap water (74.6-86.28%) and commercial stain remover (88.85-95.44%). The outcomes of this study could provide additional insights on the effect of detergent ingredients on the thermostable alkaline protease 50a activity.
Enzyme in Wasch- und Reinigungsmitteln tragen wesentlich zur Leistungssteigerung und zur Verbesserung der Umwelteigenschaften von Wasch- und Reinigungsmitteln bei. Sie sind auch wesentlich für die Differenzierung von Premium-Marken in Relation zu Standard und „Value-for-Money“-Produkten. In Waschmitteln werden Proteasen, Amylasen, Cellulasen, Lipasen, Mannanasen und Pectat-Lyasen eingesetzt. In maschinellen Geschirrspülmitteln sind es Proteasen und Amylasen. In diesem Kapitel werden Leistungsmerkmale der Enzyme und die typischen Anforderungen der verschiedenen Enzymklassen für diese Produkte besprochen. Die Vorteile der Enzymtechnologie für die Nachhaltigkeit des Waschens werden ebenso bewertet wie Aspekte von Gesundheit, Sicherheit und Umweltrelevanz. Die wirtschaftliche Bedeutung wird gestreift und ein Ausblick auf die erwartete Zukunft versucht.
Regular (1988) and compact granular (1992, 1998) laundry detergents were compared on the basis of two distinct, complementary
approaches: Environmental Risk Assessment and Life-Cycle Assessment. The results are presented in this paper and an accompanying
paper in this volume (Part II: Life-Cycle Assessment). Exposure data from The Netherlands and Sweden were used for this retrospective
analysis. The time period studied (1988–1998) spans many innovations in laundry detergents, one of which was the introduction
of compact detergents. The aquatic risk assessment resulted in risk quotients below 1 for all detergent ingredients in both
countries over the period studied. Furthermore, it showed that risk quotients decrease two to five-fold between 1988 and 1998
in each country due to the introduction of compact detergents. Slightly lower risk quotients were observed in Sweden, when
compared to The Netherlands, attributable to the lower water hardness resulting in lower detergent usage per wash cycle in
that country. If water hardnesses were equal, the outcome of the product risk assessments would also be the same in the two
countries.
The environmental profile of laundry detergents at three time points (1988, 1992, and 1998) were compared on the basis of
two distinct, complementary approaches: Environmental Risk Assessment (ERA) and Life-Cycle Assessment (LCA). The results are
presented in this paper and its accompanying paper in this issue (Part I: Product Environmental Risk Assessment). Life-Cycle
Inventory (LCI) data from The Netherlands and Sweden were used for this retrospective analysis. The chosen time period studied
(1988 - 1998) spans significant, multiple formulation and process change in laundry detergents, including the introduction
of compact, then super-compact, granular detergents. Cradle-to-Gate LCAs based on 1 kg of finished product (from raw material
supply to packaged finished product leaving the suppliers site) revealed no significant differences between the products themselves,
as manufactured between 1988, 1992 and 1998. Cradle-to-Grave LCAs based on 1000 wash cycles (from raw material supply to disposal
of used product) indicated that the consumption of raw materials and energy, as well as environmental emissions (air, water
and solid waste), decreased after the introduction of compact detergents in 1988. The LCAs revealed that a number of category
indicator values decreased (for acidification, aquatic toxicity greenhouse effects, eutrophication, toxicity, ozone depletion
and smog). Furthermore, the results of the LCAs support the conclusion that the differences between The Netherlands and Sweden
are due to (1) differences in electrical generation between the countries, (2) differences in energy consumption during consumer
use, (3) differences in detergent dosage per wash and (4) differences in the wastewater treatment infrastructure.
Surfactants are the most important ingredients in laundry detergents, hand dish washing liquids and shampoos. It is a major challenge for the industry today to identify alternative materials that are biodegradable, based on renewable resources and that show reasonable cost-performance effectiveness. Biosurfactants are an emerging class of surfactants produced by microorganisms in processes usually running at low temperatures and without large amounts of waste or by-products, therefore complying with the rules of green chemistry and potentially resulting in a lower carbon footprint than conventional surfactants.
We show in our work which biosurfactants can meet or even surpass conventional surfactants today when it comes to properties like interfacial tension reduction and wetting. Taking into account that further optimization and tailoring of materials, unique physicochemical properties and efficient production processes are within reach, the future perspectives for the broader use of biosurfactants are bright.
Replacing surfactants with enzymes in detergents helps reduce the environmental impact of laundry washing without compromising the total wash performance or increasing costs. Detergent enzymes can make this happen because they are efficient in low concentrations and ensure satisfactory cleaning at low temperatures.