17 Views no discussions “Super sand” is made using regular sand – and it could become a low-cost way to purify waterContaminated water can be cleaned much more effectively using a novel, cheap material, say researchers.Dubbed “super sand”, it could become a low-cost way to purify water in the developing world.The technology involves coating grains of sand in an oxide of a widely available material called graphite – commonly used as lead in pencils.The team describes the work in the American Chemical Society journal Applied Materials and Interfaces.In many countries around the world, access to clean drinking water and sanitation facilities is still limited.The World Health Organization states that “just 60% of the population in Sub-Saharan African and 50% of the population in Oceania [islands in the tropical Pacific Ocean] use improved sources of drinking-water.”The graphite-coated sand grains might be a solution – especially as people have already used sand to purify water since ancient times.Coating the sand But with ordinary sand, filtering techniques can be tricky.Dr Wei Gao from Rice university in Texas, US, told BBC News that regular coarse sand was a lot less effective than fine sand when water was contaminated with pathogens, organic contaminants and heavy metal ions.While fine sand is slightly better, water drains through it very slowly.“Our product combines coarse sand with functional carbon material that could offer higher retention for those pollutants, and at the same time gives good throughput,” explained Dr Gao.She said that the technique the team has developed to make the sand involves dispersing graphite oxide into water and mixing it with regular sand.“We then heat the whole mixture up to 105C for a couple of hours to evaporate the water, and use the final product – ‘coated sand’ – to purify polluted water.”Cost-efficientThe lead scientist of the study, Professor Pulickel Ajayan, said it was possible to modify the graphite oxide in order to make it more selective and sensitive to certain pollutants – such as organic contaminants or specific metals in dirty water.Another team member, Dr Mainak Majumder from Monash University in Melbourne, Australia, said it had another advantage – it was cheap.“This material demonstrates comparable performance to some commercially available activated carbon materials,” he said.“But given that this can be synthesized using room temperature processes and also from cheap graphite sources, it is likely to be cost-efficient.”He pointed out that in Australia many mining companies extract graphite and they produce a lot of graphite-rich waste.“This waste can be harnessed for water purification,” he said.Dr Wei Gao from Rice university in Texas, US, told BBC News that regular coarse sand was a lot less effective than fine sand when water was contaminated with pathogens, organic contaminants and heavy metal ions.While fine sand is slightly better, water drains through it very slowly.“Our product combines coarse sand with functional carbon material that could offer higher retention for those pollutants, and at the same time gives good throughput,” explained Dr Gao.She said that the technique the team has developed to make the sand involves dispersing graphite oxide into water and mixing it with regular sand.“We then heat the whole mixture up to 105C for a couple of hours to evaporate the water, and use the final product – ‘coated sand’ – to purify polluted water.”BBC News Share Share Tweet HealthLifestyle ‘Super sand’ to help clean up dirty drinking water by: – June 24, 2011 Share Sharing is caring!
Related Stories Storify: Scott Shafer, his family, coaches and players tweet before his final game Published on November 28, 2015 at 12:12 pm Contact Paul: [email protected] | @pschweds Syracuse head coach Scott Shafer was fired on Monday by Director of Athletics Mark Coyle. Shafer will still coach his final game against Boston College on Saturday.As fans tailgated before the BC game, here are some of their thoughts on SU’s coaching situation.Scott Littlefield, six-year season-ticket holder, SU Class of 1987“I don’t think SU should be in that ‘fire a coach every three years’ mentality. I just don’t think we’re like Alabama, Ohio State, if the guy’s not doing it, fire him and start all over again. I think SU has to be a little bit more patient with its coaches. I know Coyle’s coming in and I’m sure he was hoping it would work out, but I just don’t know what the alternatives are.”“At this point I’m kind of excited to see what happens, I just hope it’s the right move. I just hope it’s not a swing and a miss because that’s going to set us back. We’ve got this class of kids with Moe Neal and Rex Culpepper and they’re all kind of sitting on their hands not knowing what’s going to happen.”AdvertisementThis is placeholder textTim Durham, 20-year season-ticket holder“Scott Shafer plays, in my opinion, not to lose instead of playing to win. Last week was a prime example. You got fourth-and-goal from the 2 and you kick a field goal. Your season’s done anyway, you might as well go for it. He just didn’t have the guts to go for it and I think that’s why he lost his job.”Dan Chamberlain, 28-year season-ticket holder“I was upset when he got fired. I understand a little why the AD had to do it but I think Shafer, if he was given the time to do it, with what he had in place, what he was doing, he would have definitely built it into a winning program. At the very least I think he should have gotten one more year. But I understand the AD was under pressure after two losing seasons.”Ben Watkins, first-year season-ticket holder, SU Class of 2008“I think he had to be fired. If you’re going to make a move, you have to make it then. It’s kind of an unfortunate situation, he was building some momentum getting some good players in here. You could see the players played hard for him but the last couple games, a lot of silly penalties. He lost his mind two straight games … it seems like the pressure just kind of got to him a little bit.”Joel Gusman, 25-year season-ticket holder“I loved his intensity and he won me over, but in the end, after losing eight in a row, it’s tough. I respect the decision. I hope he gets another chance somewhere else but it’s time to move on.”Jeremy Conners, eight-year season-ticket holder“A change had to be made. You can’t lose games like the Virginia game, the South Florida game, the Pittsburgh game. Back-to-back three-win seasons unfortunately with below average recruiting isn’t going to cut it in today’s day and age … The downfall was in-game coaching mistakes. He just didn’t seem to learn from week to week. He seemed over his head for the position.”John Ostapovich, three-year season-ticket holder, SU Class of 1997When Shafer got hired three years ago, his passion and enthusiasm for Syracuse and the community actually encouraged me to become a season-ticket holder. … (But) it didn’t feel like he had a good feel for the game. It was hard to say whether or not he was ever going to learn that. I was always on the fence the last couple of weeks of whether or not he should go but I don’t disagree with the AD’s decision. Comments Facebook Twitter Google+