Illustration By Christoph Niemann. Source: Time
Chicago is pioneering the use of a groundbreaking new paving material which is capable of expunging the adjacent air of pollution.
As part of a raft of measures to make the streets of the Windy City more environmentally friendly, the city’s government has decided to use photocatalytic cement as a thin, permeable pavement for the bicycle and parking lanes on Blue Island Avenue and Cermak Road.
The material was developed by leading Italian cement maker Italcementi for the Vatican on the eve of the 2,000th anniversary of the Christian faith.
The seat of the Catholic Church had commissioned the construction of a new church to commemorate the event and was seeking a surface material that would be capable of retaining its pristine appearance despite being steeped in Rome’s turgid air.
Italcementi responded to the Papacy’s request by using titanium oxide to develop a photocatalytic cement. Upon exposure to natural sunlight, the titanium oxide contained in the cement triggers a chemical reaction which expedites the decomposition of any dirt or crime on its service, thus keeping itself clean.
Subsequent testing through a European research project discovered, however, that the material possessed pollution reduction properties which surpassed even the expectations of its inventors. The material was capable of cleaning up smog in adjacent air by breaking down the nitrogen oxides which are created by the burning of fossil fuels.
According to Italcementi, tests conducted in urban environments indicate that use of the material could reduce the levels of certain pollutants by 20 to 70 per cent depending on local conditions and the amount of exposed surface area.
The material is capable of achieving a very sharp reduction in air pollution within 2.5 metres of its surface, making it ideal as an environmentally friendly urban paving material as it effectively reduces the amount of smog inhaled by pedestrians.
While road surfaces in Italy and other parts of Europe have already been paved with the new material, Chicago claims to be the first city in the United States to line its own streets with the smog-cleansing cement.
Project manager Janet Attarian says road surfaces are usually neglected as spaces for the implementation of green building measures, adding that the photocatalytic cement could make a key contribution to the local urban environment.
“We tend to take the roads for granted, like ‘oh it’s just a road what can we do about it.’ But there’s actually quite a bit,” Attarian said.