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Initial results are presented for the production of hydrogen from waste lubricating oil using a chemical looping reforming (CLR) process. The development of flexible and sustainable sources of hydrogen will be required to facilitate a "hydrogen economy." The novel CLR process presented in this paper has an advantage over hydrogen production from conventional steam reforming because CLR can use complex, low value, waste oils. Also, because the process is scalable to small and medium size, hydrogen can be produced close to where it is required, minimizing transport costs. Waste lubricating oil typically contains 13-14% weight of hydrogen, which through the steam reforming process could produce a syngas containing around 75 vol% H₂, representing over 40 wt% of the fuel. The waste oil was converted to a hydrogen-rich syngas in a packed bed reactor, using a Ni/ Al₂O₃ catalyst as the oxygen transfer material (OTM).

Rhodium is an important component of three-way catalysts for emissions control on gasoline engines1. It has unparalleled activity in NOx reduction under stoichiometric conditions, where very high conversion efficiencies are required to meet current and future legislative targets. Over 90% of world rhodium usage is in such catalysts, and in recent times the price of rhodium has increased enormously2. This has lead to significant focus on reducing the quantity of rhodium required whilst still retaining the ability to meet the most stringent emissions legislation. Experiments are described where three-way catalysts employing advanced washcoat formulations and coating techniques are evaluated with a range of rhodium levels right down to 1g/ft3 which nevertheless still meet Euro 4 emissions limits after 100,000 km-equivalent bench engine ageing.

Catalyzed soot filters are being fitted to an increasing range of diesel-powered passenger cars in Europe. While the initial applications used silicon carbide wall-flow filters, oxide-based filters are now being successfully applied. Oxide-based filters can offer performance and system cost advantages for applications involving both a catalyzed filter with a separate oxidation catalyst, and a catalyzed filter-only that incorporates all necessary catalytic oxidation functions. Advanced diesel catalyst technologies have been developed for alternative advanced oxide filter materials, including aluminum titanate and advanced cordierite. In the development of the advanced catalyzed filters, improvements were made to the filter material microstructures that were coupled with new catalyst formulations and novel coating processes that had synergistic effects to give enhanced overall performance.

The exhaust gas mixture of a carburettored 2-stroke engine requires specially designed catalyst formulations if optimum pollutant conversions, durability and cost requirements are to be realised. Formulation improvements which increase the conversion of carbon monoxide (CO) allow manufacturers to tune their vehicles richer to give more power, improve rideability and promote longer engine life. In order to design catalyst formulations which facilitate engine tuning whilst still meeting legislative emissions targets, a study was performed on the effects of platinum group metal (PGM) combinations and advanced washcoat materials on CO performance. The effect of PGM and washcoat materials on fresh and aged CO conversion were assessed on vehicles representative of the European, Chinese and Indian markets. A road-correlated bench engine ageing cycle was used to simulate 30,000 km road ageing.

By characterizing current three-way catalysts (TWCs) after thermal aging, it was possible to use the information obtained to develop a new generation of more thermally durable TWCs. To assess their performance, a dynamic dynamometer was used to age these new TWC formulations (Pt/Rh and Pd/Rh) at a series of different maximum catalyst operating temperature limits (960, 1010 and 1050°C) using a proprietary transient aging cycle. Each catalyst was evaluated periodically throughout the aging on a dynamic dynamometer to assess its emission performance and aging characteristics. After a representative aging time, both the Pt/Rh and the Pd/Rh formulations were capable of meeting European Stage IV emission standards on a production powertrain after prolonged 1050°C aging. The thermal resistance of the new Pt/Rh and Pd/Rh TWCs is significantly better than that of previous technologies.

The Platinum Group Metal (PGM) content of catalyst formulations contribute significantly to the overall cost of catalytic converters for Indian carburettored 2-stroke and 4-stroke vehicles. Reducing the PGM content of these catalysts while maintaining high pollutant conversions and high durability demanded by motorcycle manufacturers and legislation, represents a significant challenge to the catalyst industry. Indian 2-stroke and 4-stroke vehicles have been used to investigate the effect of advanced catalyst formulations in combination with very low PGM loadings on transient conversion efficiency over the Indian Driving Cycle (IDC). Both conventional flow-through metallic monoliths and low cost stainless steel perforated tubes have been coated and evaluated. Static bench engine ageing has been used to simulate up to 30,000 km of on-road use and to demonstrate the exceptional durability of these new catalyst formulations.

To investigate the effect of removing phosphorus lubricant additives from engine oil, a mileage accumulation programme was run using four 1.6 litre gasoline vehicles, two of which used phosphorus based lubricant oil additives, and the other two used boron based lubricant oil additives. The work showed that the catalyst systems deactivate during mileage accumulation, but emissions were still within the European Stage IV legislative limits at the completion of the mileage accumulation programme. Vehicles run with the boron oil show lower tailpipe emissions than the vehicles run with the phosphorus oil.