Wednesday, August 6, 2014

Turning carbon dioxide emissions into chemicals, fibres and jet fuel

A carbon revolution? Scientists are using the principles of photosynthesis to turn CO2 emissions into useful products

Shell is collaborating on a project in Switzerland that will produce jet fuel, using carbon dioxide, water and solar energy. Photograph: Gerolf Kalt/ Gerolf Kalt/Corbis

Bernie Bulkin

Monday 4 August 2014 13.28 BST

When fuels are burned, the products are carbon dioxide, water, and heat. Lots of heat. This heat takes energy out of the chemicals (say petrol, coal or gas) and releases it, leaving behind very low energy molecules, like CO2. A chemist's dream is to find efficient ways of putting this energy back into the carbon dioxide to turn it into something else useful. In other words, to convert a waste product that causes global warming into something useful.

If carbon dioxide is in a product that will keep it locked up for a long period of time, like furniture or building insulation, this is a way of removing it from the air: carbon capture. And CO2 is free or, given policies to make the emission of carbon dioxide a cost to business, it even becomes a starting material for chemistry that has a negative cost.

Luckily, nature already does what chemists aspire to. It efficiently takes carbon dioxide from the air, using energy from sunlight and natural catalysts, and converts it into the carbon building blocks of plants and trees: photosynthesis. Given the intense international focus on greenhouse gases over the past decade, it is unsurprising that many chemists are trying to find routes to useful products. The challenge, as with much of chemistry, is to find synthetic catalysts that speed up reactions in a way that is as good as nature or better.

Liquid Light, a spinout from Princeton University, uses electricity and catalysts (what they are is a secret), to make chemicals from carbon dioxide, and seems to have progressed to having a near-commercial process to make ethylene glycol, a key component of anti-freeze and, more interestingly, a building block of polyester bottles and fibres. Scientists at Liquid Light believe they can tailor their catalysts to make other chemicals, and that the electricity used can come from solar panels. The company takes photosynthesis-level efficiency as the benchmark against which to measure their process, and claims it is now twice as efficient.

A German chemical company, BASF, and a US company, Novomer, are capturing CO2 from power plants or other waste sources, using novel catalysts to make polypropylene carbonate. This plastic can be used for coatings, adhesives, foams and packaging and can replace other plastics in these applications that are currently made from oil. Both companies are moving towards commercial processes. Bayer, another large German chemical company, is also advancing a process to make polyurethane foams using carbon dioxide.

A more brute force approach is that taken by the Solar Jet programme in Switzerland, led by Dr Aldo Steinfeld of ETH-Zurichcollaborating with Shell. They designed a clever reactor that generates very high temperatures from solar energy to break down carbon dioxide and water, converting them to hydrogen and carbon monoxide. From this mixture they can make kerosene for jet fuel using well-known chemical processes. This is still at an early stage – so far they have made one litre of fuel – but sometimes these high temperature processes are more straightforward to scale up than catalyst-based approaches.

Carbon dioxide utilisation is attracting clever chemists and engineers, start-up venture capital and big established players. This is an area to watch for one or more revolutions of the chemical industry in the next five years.

Turning carbon dioxide emissions into chemicals, fibers and jet fuel

Friday, August 1, 2014

Security threats with USB


We all rely on USB to interconnect our digital lives, but new research first reported by Wired reveals that there's a fundamental security flaw in the very way that the humble Universal Serial Bus functions, and it could be exploited to wreak havoc on any computer.
Wired reports that security researchers Karsten Nohl and Jakob Lell have reverse engineered the firmware that controls the basic communication functions of USB. Not only that, the've also written a piece of malware, called BadUSB, that can "be installed on a USB device to completely take over a PC, invisibly alter files installed from the memory stick, or even redirect the user's internet traffic."
Embedded within USB devices—from thumb drives thorough keyboards to smartphones—is a controller chip which allows the device and a computer it's connected to send information back and forth. It's this that Nohl and Lell have targeted, which means their malware doesn't sit in flash memory, but rather is hidden away in firmware, undeletable by all but the most technically knowledgable. Lell explained to Wired:
"You can give it to your IT security people, they scan it, delete some files, and give it back to you telling you it's 'clean... [But these] problems can't be patched. We're exploiting the very way that USB is designed."

The kicker is that it's virtually impossible to check whether a device's firmware has been tampered with, and even if it was, there's no single trusted version of it to check against. It's also worth pointing out that it can travel both ways: a USB stick could infect a computer with its malware, say, and the PC could then infect any USB device plugged into it.
So it's fairly worrying that the pair of researchers have demonstrated—and will present at the upcoming Black Hat security conference in Las Vegas—that the flaw can be exploited on thumb drives, mice, keyboards and even an Android smartphone. (It should, in theory, work on any USB device that can have its firmware reprogrammed).Some of Wired's sources even speculate that the hack could already be being used by the NSA.
That's a lot of bad news—so what can you do about it? Technically speaking, very little: there's no patch of code that can be be used to solve the problem. Instead, both the USB Implementers Forum and the researcherspoint out that a change in the way we use USB is the only solution: don't plug a USB device into any computer you don't 100 percent trust, and don't plug untrusted USB device into your computer either. That may prove inconvenient—but it may also save you from a very nasty surprise, too. [Wired

USB Has a Fundamental Security Flaw That You Can't Detect

 
Hi-Tech Talk © 2015 - Designed by Templateism.com