The chemical industry shrinks its carbon footprint with more environment friendly products

05 February 2007 00:00  [Source: ICB]

The chemical industry is introducing new products that are greener, more environment friendly, or that have a smaller carbon footprint than traditional goods

Dow Corning solar cell materials

World demand for energy will more than double by 2050, and more than triple by the end of the century. Incremental improvements in fossil fuels will not be adequate to supply this demand in a sustainable way.

However, there is enough energy coming from the sun to more than meet the electricity power needs of the global population. One of the main obstacles to the adoption of solar energy has been the availability of silicon feedstock, which is used to make solar cells. The production of solar cells requires silicon in its purest and, consequently, least available form: polycrystalline silicon, also in semiconductor devices and advanced flat panel displays.

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For years, the solar industry supply chain has been trying to develop efficient solar cells from more abundant metallurgical-grade-derived silicon. Dow Corning has developed such a solution: Dow Corning PV 1101 SoG (Solar Grade) Silicon is the first industrial-scale silicon feedstock material, from a supply chain dedicated to the photovoltaics industry, that can be blended with polycrystalline silicon and exhibit solar cell performance characteristics equivalent to pure polysilicon.

Testing shows that PV 1101 SoG Silicon can be used to supplement polysilicon to volume manufacture solar cells without degrading cell performance.

The PV 1101 material and next generation solar grade feedstock under development at Dow Corning have the potential to increase the total availability of feedstock to photovoltaic producers while also allowing for shorter energy payback of devices. PV 1101 is a complementary feedstock material offering supply, technical and business model options to photovoltaic producers globally.

www.dowcorning.com

Akzo Nobel fully recyclable barrier coating

Paper and cardboard are far from ideal materials for making pizza boxes and coffee cups, so special coatings are needed to give them a barrier that is both water- and grease-resistant.

There is little new about the application of such barrier coatings on paper and cardboard. However, Akzo Nobel has developed innovative high-quality coatings from recycled waste.

These products, in turn, are also recyclable, helping to further reduce the ecological footprint that this key industry leaves.

Akzo Nobel's EvCote product range comprises water-based polyethylene terephthalate (PET) coatings that are made from reclaimed and recycled post-consumer municipal-waste materials.

Using waste products as a feedstock means that the resources invested in their original manufacture are re-used.

EvCote products are recyclable, biodegradable and compostable, which means that their use contributes towards the reduction of major environmental problems.

EvCote-treated paper and board are also fully recyclable.

A full eco-efficiency analysis of the product range has been carried out. This took into account the consumer behaviour of end-users, as well as various recycling and disposal options.

Other products that dominate the industry can offer some comparable benefits, but often at a cost to the environment.

Wax, for example, is not recyclable at all, and polyethylene (PE) is economical but difficult to recycle.

While PET as a polymer backbone is one of the cheapest raw materials, the biggest financial benefits of EvCo products are generated at the end of the value chain.

The recyclable nature of the products means that disposal is not a costly part of their lifecycle.

www.akzonobel.com

Shell chemicals timber preservation

Timber such as pine and eucalyptus is widely used to build homes and buildings where long-term durability is required.

But timber is subject to environmental challenges, such as attack from insects and fungi, or moisture-based decomposition.

To extend durability, construction timber is often bathed in an aqueous solution of copper, chromium and arsenic acids. While effective, this method is under scrutiny for its possible health effects on workers, and for environmental issues when disposing of treated lumber.

As part of the search for more sustainable treatments, Shell chemicals companies in Australia and New Zealand are collaborating with some of the leading timber preservation chemical companies to introduce hydrocarbon solvents as the carrier for active preservative ingredients. The result is a timber-treatment process that is based on light organic solvent preservatives (LOSP).

The advent of the LOSP process is timely, as demand for construction timber has put pressure on the supply chain to create shorter lead times from tree harvesting to final use. The LOSP process has responded well to this challenge because it is easy to use and cost efficient.

The solvents used in the LOSP process are clear liquids, chemically stable, non-corrosive and have a mild odour. They provide adequate solvency both to hold the active ingredients in suspension and to penetrate the timber fibre. They are relatively fast drying, making them economical to use.

www.shell.com/chemicals/solvents

SigmaKalon biocide-free antifouling coating

Mounting pressure and legislation are supporting the development of antifouling coating products that do not damage the environment.

Such coating systems usually rely on biocides to kill or chemically deter fouling organisms.

SigmaKalon has developed SigmaGlide, which is a biocide-free, environmentally-friendly coating, with the ability to "release" fouling settlement from the hulls of ships because of its exceptionally smooth silicone-based structure.

It works by having a low surface energy, which is created by a slick, slippery surface, to which fouling organisms, animal or plant, have difficulty adhering.

Some microfouling may settle on SigmaGlide when the ship is idle, but once the vessel moves, water motion will cause the fouling to detach.

The development of silicone-based fouling release systems has taken years because the challenge has been to create a coating that is "non-stick", yet is capable of adhering to the underlying anticorrosive system.

To address this, there are two products in the SigmaGlide system: the "tiecoat" (SigmaGlide 790) and the "finishcoat" (SigmaGlide 890).

The tiecoat gives the silicone system the important adhesion to the substrate, and the finish gives the smooth surface and fouling release properties.

SigmaGlide can provide fouling release at very slow speeds - down to five knots - as well as working equally efficiently at high speeds.

It is, therefore, ideal for low-activity vessels, such as barges and tugs, larger vessels, such as gas carriers and container ships, up to very fast ferries travelling at 42 knots.

Smooth hulls mean significant cost savings on fuel, at a time when fuel prices are at an all-time high.

www.sigmakalon.com

BASF helps moderate housing environment

Summer, sun and hot days - although much longed-for during the winter, they can soon become too much of a good thing when they arrive.

Modern houses, made of lightweight construction, and office complexes of steel and glass, can turn into a sauna overnight.

BASF's Micronal PCM offers a solution to this problem.

Micronal PCM is microscopically small polymer spheres containing a wax storage medium in their cores, which, when incorporated in plasters or gypsum wallboards, melt and solidify, and regulate environmental temperatures.

The waxes contained in Micronal PCM melt at 23C or 26C, depending on the application. On melting, they absorb large amounts of heat from the environment, thereby preventing the room temperature from rising further.

At night, the heat that is bound when the wax solidifies is released again, and the heat storer is ready for a new summer's day.

The cooling effect of about 3C to 4C is almost equivalent to that provided by conventional air-conditioning systems, which are usually designed to create a temperature difference of 6C.

Over the past five years, Micronal PCM has successfully made the transition from the laboratory into practical use.

In Freiburg, Germany, the Sonnenschiff (Solar Ship), an innovative building complex, which has a 6,500m2 floor area, has just been completed.

During winter, thorough insulation and use of incident solar energy minimise the energy costs of the Sonnenschiff, which requires hardly any heating.

Sonnenschiff architect Rolf Disch explains that, besides the Venetian blinds that provide sunscreening, Micronal PCM SmartBoard - BASF's innovative gypsum-based PCM-containing wallboards - is an integral part of the building's cooling concept.

www.micronal.de

Ciba Specialty Chemicals, green curing products

Ciba Specialty Chemicals pioneered UV curing technology more than 30 years ago as an alternative to solvent-based formulations in the printing, packaging, electronics and wood product industries.

The approach was the first to polymerise low-solvent, acrylate-based coatings and inks using a UV light source instead of a heat oven.

UV curing technology offers not only quality and process benefits, including higher productivity and cure on demand, but green benefits, too.

"By allowing curing to be performed at lower temperatures or within shorter periods of time, UV curing reduces energy use, carbon dioxide emissions and costs relative to traditional curing methods, which rely on heat to trigger the reaction," explains Hermann Angerer, global head of Ciba Specialty Chemicals' coating effects business.

The technology also leads to low - or no - volatile organic compounds, helping manufacturers to meet or to exceed emission and air-quality regulations.

Until recently, however, only those that used acrylate-based binders, or about 6% of the market, could take advantage of the technology.

Now, Ciba has developed a new approach to photo-triggered base catalysis that enables UV curing of a much wider range of binders in automotive and industrial coatings, such as epoxy and polyurethane (PU).

Known as photolatent base curing, this innovative, patented methodology offers greater flexibility, thanks to a novel catalyst that is specially developed for base-catalysed crosslinking mechanisms.

"Our photolatent base technology platform allows the design of completely new resin types with improved coating properties," says Angerer.

www.cibasc.com

DuPont biopolymer feedstock

Late last year, DuPont and Tate & Lyle made the first commercial shipments of 1,3-propanediol (Bio-PDO) from their $100m (€77m) joint-venture site in Loudon, Tennessee, US. The Loudon facility produces Bio-PDO from renewable resources - in this case, corn sugar - making it the first facility in the world to make this new bio-based product.

The joint venture uses a proprietary fermentation process that was developed by DuPont and Tate & Lyle to produce Bio-PDO using corn instead of petroleum-based feedstocks. The production of Bio-PDO consumes 40% less energy and reduces greenhouse gas emissions by 20% compared with petroleum-based propanediol.

Production of 45,400 tonnes/year of Bio-PDO will save the energy equivalent of 10m gal/year of gasoline, enough to fuel 22,000 cars/year.

The first shipments of Bio-PDO were sent to DuPont for the manufacture of DuPont Sorona polymer, and to a customer evaluating a new industrial product formulated with Bio-PDO.

Bio-PDO can be used in a variety of applications, either by itself or as an ingredient in the production of materials that have traditionally been based on petroleum feedstocks.

Bio-PDO is also a key ingredient for Sorona, DuPont's newest polymer family.

Sorona is a high-performance polymer that offers a unique combination of attributes in a variety of applications.

As a carpet fibre, Sorona provides permanent stain protection, in addition to softness and durability. In apparel, Sorona contributes exceptional softness, comfort stretch and recovery, easy care and UV- and chlorine-resistance.

www.dupont.com

Air Products green surfactants

Increasing environmental regulations and the continuing need to boost productivity are driving manufacturers of industrial and institutional cleaners to seek cost-effective raw materials with reduced environmental impact.

Air Products can offer these manufacturers efficient, environmentally friendly drop-in replacements for phenol-containing surfactants, or, more specifically, nonyl-phenol ethoxylate (NPE) surfactants.

For years, NPEs were a staple of the chemical industry. However, with the passage of the Detergents Regulation in October 2005 in Europe, there has been a shift to biodegradable surfactants in detergent and cleaning solution applications in Europe.

A common substitute for NPE surfactants in Europe are linear alcohol ethoxylate surfactants.

Although no such legislation has been promulgated to date in the US, the Environmental Protection Agency (EPA) has issued a letter to users of NPEs requesting that they start transferring to other products.

Perhaps more influential than even the EPA is US retail giant Wal-Mart, which has said that it will no longer stock products containing NPEs.

Air Products produces a range of alcohol ethoxylate surfactants under the Tomadol trade name, which give I&I manufacturers superior removal of heavy soils at much lower concentrations than those containing NPEs.

Besides the lower concentration of surfactants, solutions using Tomadol surfactants also use much less solvent than NPE-containing solutions that enable the manufacturer to meet increasing restrictions on total volatile organic compound content.

Tomadol surfactants also offer much faster solution times, and a lower viscosity profile, which can increase asset utilisation/productivity for the cleaning solution manufacturer.

www.airproducts.com

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