Duncan J. Macquarrie

Handbook of Green Chemistry and Technology

Contributors Preface Introduction Principles of sustainable and green chemistry Chemistry and the environment Green chemistry and sustainable development Life cycle assessment: A tool for identification of more sustainable products and processes Industrial processes using solid acid catalysts Micelle templated silicas as catalysts in green chemistry Polymer-supported reagents Biocatalysis Recent advances in phase transfer catalysis Hydrogen peroxide in waste minimisation - current and potential contributions Waste minimisation in pharmaceutical process development: Principles, practice and challenges Green catalysts for industry Green chemistry in practice Process intensification for green chemistry Sonochemistry Applications of microwaves for environmentally benign organic chemistry Photochemistry Electrochemistry and sustainability Fuel cells: a clean energy technology for the future Supercritical carbon dioxide as an environmentally benign reaction medium for chemical synthesis Chemistry in fluorous biphasic systems Extraction of natural products with superheated water Index

Direct preparation of organically modified MCM-type materials. Preparation and characterisation of aminopropyl–MCM and 2-cyanoethyl–MCM

Very stable organically modified MCMs are prepared by a simple one-step procedure from readily available starting materials.

Green chemistry and the biorefinery: a partnership for a sustainable future

Research into renewable bioresources at York and elsewhere is demonstrating that by applying green chemical technologies to the transformation of typically low value and widely available biomass feedstocks, including wastes, we can build up new environmentally compatible and sustainable chemicals and materials industries for the 21st century. Current research includes the benign extraction of valuable secondary metabolites from agricultural co-products and other low value biomass, the conversion of natures primary metabolites into speciality materials and into bioplatform molecules, as well as the green chemical transformations of those platform molecules. Key drivers for the adoption of biorefinery technologies will come from all stages in the chemical product lifecycle (reducing the use of non-renewable fossil resources, cleaner and safer chemical manufacturing, and legislative and consumer requirements for products), but also from the renewable energy industries (adding value to biofuels through the utilisation of the chemical value of by-products) and the food industries (realising the potential chemical value of wastes at all stages in the food product lifecycle).

Structure and reactivity of sol–gel sulphonic acid silicas

A range of mesoporous solid sulphonic acid catalysts have been prepared from a mercaptopropyl-trimethoxysilane (MPTS) precursor by sol-gel synthesis. The creation of surface sulphonic acid functionality via thiol oxidation has been followed by XPS and Raman spectroscopy. It is possible to continuously vary the sulphonic acid loading from 1 to 12wt.% while maintaining pore volume and mesostructure. The resulting materials exhibit high thermal stability and acid strength across the composition range and show good activity and selectivity in esterification and condensation reactions.

Chitosan-based heterogeneous catalysts for Suzuki and Heck reactions

Novel supported palladium catalysts have been developed based on chitosan as a support. These catalysts display excellent activity in the Suzuki and Heck reactions.

Palladium nanoparticles on polysaccharide-derived mesoporous materials and their catalytic performance in C–C coupling reactions

Palladium nanoparticles were successfully prepared using porous materials derived from starch as support media. The nanoparticle size distribution was controllable by selection of the preparation solvent. Materials were characterised and catalytically tested in various C–C coupling reactions, exhibiting excellent catalytic activities in the microwave-assisted Heck, Suzuki and Sonogashira reactions. The palladium-supported materials were also reusable, preserving their catalytic activities after four reuses.

Versatile mesoporous carbonaceous materials for acid catalysis

Starbon mesoporous materials were synthesized after pyrolysis of expanded starch and subsequently functionalised with sulfonated groups, providing highly active and reusable materials in various acid catalysed reactions.

Organomodified hexagonal mesoporous silicates

A neutral templating route to organically modified silicates with tightly controlled porosity is described. The materials prepared are characterised and compared to the corresponding organofunctionalised silica.

A novel Suzuki reaction system based on a supported palladium catalyst

A range of supported palladium complex-catalysed Suzuki reactions is described with notable features including fast and efficient reactions, excellent catalyst recyclability, and total catalyst stability under the reaction conditions. We have achieved turnover numbers of several thousand based on ten re-use experiments from batch reactions in air. Our system not only solves the basic problems of catalyst separation and recovery but also avoids the use of phosphine ligands.

The preparation of high-grade bio-oils through the controlled, low temperature microwave activation of wheat straw

The low temperature microwave activation of biomass has been investigated as a novel, energy efficient route to bio-oils. The properties of the bio-oil produced were considered in terms of fuel suitability. Water content, elemental composition and calorific value have all been found to be comparable to and in many cases better than conventional pyrolysis oils. Compositional analysis shows further differences with conventional pyrolysis oils including simpler chemical mixtures, which have potential as fuel and chemical intermediates. The use of simple additives, e.g. HCl, H(2)SO(4) and NH(3), affects the process product distribution, along with changes in the chemical composition of the oils. Clearly the use of our low temperature technology gives significant advantages in terms of preparing a product that is much closer to that which is required for transport fuel applications.