Canada-based QuestAir Technologies Inc produces equipment to purify gas. This purification technology has enabled QuestAir to diversify into hydrogen fuelling equipment for service stations and biogas purification plants. The company, which is quoted on Aim and the Toronto Stock Exchange, develops advanced pressure swing adsorption gas purification systems. QuestAir joined Aim on 21 December 2004 and raised £6.4.1m in a placing at 74.5p a share – 745p post-share consolidation. A 10-for-one share consolidation happened on 27 June 2008. QuestAir's technology differs from the mainstream technology because it doesn't use beaded adsorbents. Instead it uses a material that overcomes the fluidisation limitations of the beads. That enables the equipment to reach higher speeds and to be much smaller. This technology is used to purify hydrogen for use in the refining of high sulphur oil. It helps to remove the sulphur and environmental regulations are cutting the level of sulphur allowed in diesel. The technology can also be used to recover waste hydrogen from petrochemical plants, upgrade contaminated natural gas and for biogas plants. The latter is the renewed focus of the business. Longer-term the technology can be used to supply hydrogen for vehicles. According to QuestAir its hydrogen purification technology “offers a compact and cost-effective gas separation solution to reformer-based hydrogen refuelling stations”. QuestAir also believes that its technology can be used to combat the CO problem associated with reforming in PEM fuel cell systems. It removes the CO and other impurities from the output of the reformer unit, providing purified hydrogen to the anode side of the PEM fuel cell. QuestAir believes the technology will be a compact alternative to current technologies for CO removal such as selective oxidizers or preferential oxidizers (PrOx). In addition, it argues that it could increase the efficiency of PEM systems compared with PEM systems that utilize PrOx technology. Shell is a shareholder in QuestAir.