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2nd Manufacturing Using Sustainable Chemistry meeting – York Science Park

05 Jan 2012

The Green Chemistry Centre in conjunction with the CIA (Chemical Industries Association) is organising the 2^nd MUSC (Manufacturing Using Sustainable Chemistry) event, which will take place on Thursday 16th February 2012 at the Innovation Centre, York Science Park.

The event will be centred around Microwave-enhanced chemistry and the alternative uses of microwave heating. It will coincide with the opening of the Biorenewables Development Centre (BDC) on the York Science Park. The biorefinery R&D facility will be unique to the UK and will showcase state-of-the-art microwave-biomass processors and other clean chemical and white biotechnology with open-access to academic and industrial collaborators. The programme for the day will consist of presentations, poster sessions and a tour of the BDC. Speakers will include Mike Lancaster of the CIA, Dr Adrian Higson of the NNFCC and Dr Marilena Radoiu of Sairem.

Please see this web link to the flyer and registration form: http://www.musc-network.co.uk/flyer%20and%20form.pdf

You may also be interested in Starbons^® Day at the Green Chemistry Centre on the 16th July 2012 – please see the flyer for further details: http://www.greenchemistrynetwork.org/pdf/starbons_day_flyer.pdf

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Critical review: The photoreaction of TiO2 and Au/TiO2 single crystal and powder surfaces with organic adsorbates. Emphasis on hydrogen production from renewables

14 Dec 2011

In this critical review, Karen Connelly and Hicham Idriss from the University of Aberdeen, UK and SABIC T&I, Saudi Aradia, review the fundamental aspects behind the reactivity of TiO₂ surfaces.

The authors look at both rutile-TiO₂and a gold/TiO₂system and the various factors that affect their reactivity, before studying the photoreaction of ethanol in more detail. Here, they show that the gold/TiO₂system shows about two orders of magnitude high activity that rutile-TiO₂and discuss the mechanisms of hydrogen production. However, the authors highlight that further work is still needed in this field as only one third of the hydrogen is extracted from the ethanol. They highlight that the challenge will be in designing photocatalysts for hydrogen production that are capable of breaking carbon-carbon bonds under ambient conditions.

This article is free to access until the 11th January 2012! Click the link below to read more…

The photoreaction of TiO₂and Au/TiO₂single crystal and powder surfaces with organic adsorbates. Emphasis on hydrogen production from renewables, Karen A. Connelly and Hicham Idriss, Green Chem., 2012, DOI: 10.1039/C1GC15992E

You may also be interested in this article, also free until the 11th January 2012:

Sustainable hydrogen production by the application of ambient temperature photocatalysis, Michael Bowker, Green Chem., 2011, 13, 2235-2246

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A quantitative comparison between conventional and bio-derived solvents from citrus waste in esterification and amidation kinetic studies

08 Dec 2011

(R)-(+)-Limonene and its close derivative p-cymene has been shown to be viable yet sustainable alternative solvents for amidation and esterification reactions.

James Clark and colleagues from the University of York, UK report the use of bio-derived solvents from citrus waste and their application in some organic reactions. Approximately 15 million tons of citrus waste is generated annually, but it is usually disposed of or incorporated into animal feed. However, this waste material provides excellent opportunities to obtain useful and/or valuable chemicals. Here, limonene obtained directly from citrus wastes, and p-cymene which can be synthesised easily from waste biomass, have been shown to be viable alternatives to conventional solvents in esterification and amidation reactions.

This article is free to access until the 16th January 2012! Click the link below to find out more…

A quantitative comparison between conventional and bio-derived solvents from citrus waste in esterification and amidation kinetic studies, James H. Clark, Duncan J. Macquarrie and James Sherwood, Green Chem., 2012, DOI: 10.1039/C1GC16299C

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Green Chemistry issue 12 now online

05 Dec 2011

Green Chemistry issue 12 is now online!

The front cover of this issue features work by Sibudjing Kawi and W. Thitsartarn from the National University of Singapore. They report a stable and active CaO-CeO₂ catalyst, prepared by simple gel formation viaa co-precipitation method, which was applied to the transesterification of oil to biodiesel. The catalyst could be reused up to 18 times without significant loss of activity and showed only low amounts of leaching. Find out more by reading the full article ‘An active and stable CaO–CeO₂catalyst for transesterification of oil to biodiesel.’

The inside front cover highlights work from Jérôme Husson and co-workers from the Université de Franche-Comté. They report a new synthesis route to 4,4′,4′′-tricarboxy-2,2′:6′,2′′-terpyridine, a ligand that is a component of the “Black-dye” sensitizer for dye-sensitized solar cells. The route developed by Husson has a lower ecological impact with respect to atom economy, yield, solvent and chemicals used and wastes generated, compared to the previously reported method. Find out more by reading the full article ‘A more efficient synthesis of 4,4′,4′′-tricarboxy-2,2′:6′,2′′-terpyridine.’

These articles are free to access until 16th January 2012!

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Liquid hydrocarbon fuels from cellulosic feedstocks via thermal deoxygenation of levulinic acid and formic acid salt mixtures

01 Dec 2011

US scientists have developed a route to produce liquid hydrocarbon fuels in high yields from cellulosic feedstocks.

Conversion of cellulosic feedstocks into liquid hydrocarbon transportation fuels could have a large impact on supplying our future energy needs. However, at present two barriers hinder it’s commercial implementation; first, the high cost per unit product as the feedstock energy feed rate is much smaller than in the petroleum industry; and secondly, the high operating cost to convert cellulosic material into energy dense biofuels partly due to the high cost of removing oxygen from the biomass.

In this work, Clayton Wheeler and colleagues from the Bioproducts Research Institute at the University of Maine, USA have used formic acid as a hydrogen source in the thermal deoxygenation of levulinic acid, giving high yields of deoxygenated hydrocarbons. This methods has significant advantages, providing a high-yield, robust, low-pressure, non-catalytic route to hydrocarbon mixtures from biomass, which are similar to petroleum crude oils.

This article is free to access until the 6th January 2012! Click below to find out more…

Liquid hydrocarbon fuels from cellulosic feedstocks viathermal deoxygenation of levulinic acid and formic acid salt mixtures, Paige A. Case, Adriaan R. P. van Heiningen and M. Clayton Wheeler, Green Chem., 2012, DOI: 10.1039/C1GC15914C

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A simple direct phosgeneless route to N-heteroaryl unsymmetrical ureas

29 Nov 2011

Scientists from Italy have developed a simple and green approach to the synthesis of N-heteroaryl unsymmetrical ureas avoiding the use of phosgene.

N-heteroaryl unsymmetrical ureas are widely used as synthetic intermediates and usually possess biological activityor interesting pharmacological properties. However, traditional methods used to synthesis these compounds usually involve phosgene or phosgene-derivatives, a toxic and harmful reagent on which government policies are placing larger constraints on its usage for environmental protection.

In this work, Eugenio Quaranta and co-workers have developed a route to N-heteroaryl unsymmetrical ureas via the reaction of N-phenoxycarbonyl derivatives of pyrrole, indole and carbazole with amines. The reaction can be catalyzed by DBU under mild conditions providing the desired target molecules in good yields, avoiding traditional multistep procedures and without using phosgene or its derivatives.

This article is free to access until the 6th January 2012! Click below to find out more…

A simple direct phosgeneless route to N-heteroaryl unsymmetrical ureas, Marianna Carafa, Valentina Mele and Eugenio Quaranta, Green Chem., 2012, DOI: 10.1039/C1GC15984D

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Electrostatic immobilization of an olefin metathesis pre-catalyst on iron oxide magnetic particles

25 Nov 2011

Andrea Robinson and colleagues from Monash University, Australia, have developed an immobilized catalyst for ring closing metathesis (RCM) of olefins allowing for easy removal and recovery of the catalyst.

A quaternary ammonium Hoveyda-Grubbs metathesis pre-catalyst was made in one step from the commercially available second generation Grubbs catalyst, before electrostatic immobilization onto magnetic iron oxide particles. The resulting catalyst provided pseudo-homogeneous reactivity but coupled with an easy recovery option. The catalyst could simply be magnetically retrieved from the reaction media and the catalyst reused up to six times.

This article is free to access until the 23rd December 2011! Click on the link below to find out more…

Electrostatic immobilization of an olefin metathesis pre-catalyst on iron oxide magnetic particles, Matthew J. Byrnes, Andrew M. Hilton, Clint P. Woodward, William R. Jackson and Andrea J. Robinson, Green Chem., 2012, DOI: 10.1039/C1GC16084B

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Near-critical water, a cleaner solvent for the synthesis of a metal–organic framework

21 Nov 2011

A new porous co-ordination polymer has been synthesised in near-critical water which could broaden the synthetic strategies available for the environmentally friendly construction of metal-organic frameworks.

Metal-organic frameworks (MOFs) have received a lot of attention in recent years due to their potential applications in several areas, but in particular for hydrogen storage. However, MOFs are often prepared using solvothermal routes typically involving significant quantities of toxic organic solvents.

In this work Martyn Poliakoff and Martin Schröder and colleagues from the University of Nottingham and Diamond Light Source, UK, have developed a route to synthesise these Zn co-ordination polymers using near-critical water (300°C) as a cleaner alternative to organic solvents. The zinc complex can be isolated without any water molecules bound to the Zn(II) centres, in contrast to solvothermal synthesis in DMF. In addition, the use of water in this synthetic strategy potentially allows for the reuse and recovery of water from the reaction opening up possible industrial applications.

This article is free to access until the 20th December 2011! Click on the link below to find out more…

Near-critical water, a cleaner solvent for the synthesis of a metal–organic framework, Ilich A. Ibarra, Peter A. Bayliss, Eduardo Pérez, Sihai Yang, Alexander J. Blake, Harriott Nowell, David R. Allan, Martyn Poliakoff and Martin Schröder, Green Chem., 2012, DOI: 10.1039/C1GC15726D

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Continuous flow reactors: a perspective

17 Nov 2011

In this Tutorial Review, Charlotte Wiles of Chemtrix BV and Paul Watts of the University of Hull, look at the developments made in the application of continuous flow reactors for sustainable chemical research and production.

The review looks at the 12 principles of green chemistry, as outlined by Paul Anastas et al.¹and identifies which of these principles have the potential to benefit from flow reactor technology and discuss relevant examples. The authors also focus on production-scale processes, highlighting that reactor safety is key here and being able to easily scale-up bench processes to production scales. However, there are still challenges facing flow reactor technology and areas which still require further development, such as the manipulation of slurries and the recovery of solvents and catalysts.

1. P. T. Anastas and M. M. Kirchhoff, Acc. Chem. Res., 2002, 35, 686–694.

This article is free to access until the 15th December 2011! Click the link below to read more…

Continuous flow reactors: a perspective, Charlotte Wiles and Paul Watts, Green Chem., 2012, DOI: 10.1039/C1GC16022B

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Green Chemistry Blog

Archive for the ‘Uncategorized’ Category

2nd Manufacturing Using Sustainable Chemistry meeting – York Science Park

Top cited Green Chemistry articles from 2011

Critical review: The photoreaction of TiO2 and Au/TiO2 single crystal and powder surfaces with organic adsorbates. Emphasis on hydrogen production from renewables

A quantitative comparison between conventional and bio-derived solvents from citrus waste in esterification and amidation kinetic studies

Green Chemistry issue 12 now online

Liquid hydrocarbon fuels from cellulosic feedstocks via thermal deoxygenation of levulinic acid and formic acid salt mixtures

A simple direct phosgeneless route to N-heteroaryl unsymmetrical ureas

Electrostatic immobilization of an olefin metathesis pre-catalyst on iron oxide magnetic particles

Near-critical water, a cleaner solvent for the synthesis of a metal–organic framework

Continuous flow reactors: a perspective

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