Production of active carbons from waste tyres - a review

A review of the production of activated carbons from waste tyres is presented. The effects of various process parameters, particularly, temperature and heating rate, on the pyrolysis stage are reviewed. The influence of activating conditions, physical and chemical, nature of the activation chemicals, on the active carbon properties are discussed. Under certain process conditions several active carbons with BET surface areas over 1000 m(2)/g have been produced with extensive micropore volumes, over 40\% of the total pore volume. A review is carried out of the reaction kinetic modeling applied to the pyrolysis of tyres and the chemical activation of tyres. The models cover one step and two step pyrolysis models, plus more recent models which are based on the actual chemical components such as natural rubber. SBR and other additives. (C) 2004 Elsevier Ltd. All rights reserved

Effect of operating conditions on scrap tire pyrolysis

The ever growing focus on environmental issues has raised concerns about scrap tires, whose major component - vulcanized rubber - does not degrade easily. When burned, tires release toxic gases containing substantial amounts of sulfur and ammonia in addition to other pollutants. Dumped on empty city lots, tires are also a breeding ground for mosquitoes. Many proposals have been put forward to handle the disposal of scrap tires, but none of them have proved to offer a definitive solution. The study reported here investigated the production of fuel oil and activated carbon from the pyrolysis of scrap tires. The initial mass of rubber yielded approximately 46% of oil, 40% of activated carbon and 14% of gases. The resulting activated carbon displayed a specific surface area of 200 m².g-1

Adsorption-oriented processes using conventional and non-conventional adsorbents for wastewater treatment

International audienceThe removal of contaminants from wastewaters is a matter of great interest in the field of water pollution. Amongst the numerous techniques of contaminant removal, adsorption using solid materials (named adsorbents) is a simple, useful and effective process. The adsorbent may be of mineral, organic or biological origin. Activated carbon is the preferred material at industrial scale and is extensively used not only for removing pollutants from wastewater streams but also for adsorbing contaminants from drinking water sources (e.g. rivers, lakes or reservoirs). However, its widespread use is restricted due to high cost. In the last three decades, numerous approaches have been studied for the development of cheaper and more effective adsorbents capable to eliminate pollutants at trace levels. This chapter gives a general overview of liquid-solid adsorption processes using conventional and non-conventional materials for pollutant removal. It outlines some of the principles of adsorption and proposes a classification for the different types of materials. Finally, the chapter discusses different mechanisms involved in the adsorption phenomena