Tag Archives: recycling

Rechargeable Batteries from Packing Materials

Sweden was in the news recently for their extreme recycling capacity. Swedes recycle waste to the extent that they have to import garbage from other countries for use as landfills. Others countries struggling to recycle their garbage may be interested in generating rechargeable batteries from discarded packing materials that do not degrade when used as landfills.

At Purdue University, researchers have found a new way to recycle discarded peanut-shaped packing materials. They are turning these materials into components that can be used for making rechargeable batteries. Additionally, they claim their batteries can outperform those currently in use.

Packing materials have always presented a challenge when they have to be disposed. It is not very cost-effective to recycle them. For one, they are light and their large size makes it expensive to transport them to the recycling center. Additionally, they take up a lot of space in landfills. Vinodkumar Etacheri, Ph.D. explained this in a presentation of the research at the National Meeting & Exposition of the American Chemical Society.

The other reason why packing materials are not suitable is they can be harmful to the environment. Although they may not contain CFCs or ozone depleting gasses, packing materials are usually made from recycled or new polystyrene, which was also used for making Styrofoam. While the exact constituents may vary, packing materials usually contain different types of chemicals.

Among them may be potentially harmful substances such as heavy metals, chlorides and phthalates. These leach into the environment easily when in a landfill. They deteriorate the soil and water quality. Although marketers claim newer material they use for making packing material is more environmentally friendly, the chemicals and detergents used in the starch-based alternatives also contaminate the ecosystem.

A new process developed by the researchers converts the packing material into high-tech nano-particles and carbon micro sheets. These are useful in making anodes for rechargeable batteries.

Lithium ion batteries have lithium ions moving between electrodes as the batteries charge and discharge. When the new anodes replace the conventional graphite ones in commercial lithium ion batteries, the performance gain is dramatic. The anodes made of nano-partcles and carbon micro sheets increase the storage capacity of the lithium ion batteries several folds.

The porous microstructure of the new anodes allows the lithium ions to diffuse in quickly and create more surface area within the micro sheets. The increased surface area offers greater electrochemical interactions. In addition, the disordered crystal structure and the porous nature of the new anodes can store more lithium ions beyond their theoretical limit.

According to the researchers, they use a relatively low temperature for the new process. This is a crucial factor in producing these new materials with their advantageous architecture. While other researchers make micro sheets at temperatures as high as 4,000°F, researchers at Purdue University have kept the temperature of their process at only 1,100°F. Instead of the more layered arrangement of carbon atoms at the higher temperature, the lower temperature generates less-ordered materials. That actually increases the electrical storage capacity by about 15%. The lower temperature process also allows the materials to remain more environmentally friendly.

New Method for Recycling PCB Waste

All over the world, gadgets contain Printed Circuit Boards or PCBs as a means of mounting and interconnecting the several electronic components they use. When the life of the gadget comes to an end, nearly all components are recycled. Although the recycling process is streamlined in some countries, it is still a growing industry in most developing countries. It is especially difficult to recycle the PCB and its components, since it often produced significant waste streams. Researchers in China have developed an innovative method to salvage the materials found in waste PCBs.

Every year, e-waste produced around the globe reaches nearly 50-million tons, most of which ends up in the developing countries such as China and India. Now, there is a friendly method for salvaging materials from waste PCBs. Using the solvent Dimethyl Sulfoxide or DMSO, Chinese researchers claim to have developed an environmentally friendly method that can simplify the process of recycling e-waste, especially waste PCBs.

Traditional methods of recovering precious metals from waste PCBs include using pyrolysis along with hydrometallurgical processes. The process uses aqueous solvents such as strong alkalis and acids. However, these processes are not environmentally friendly. They contaminate the environment with toxic heavy metals including persistent organic pollutants. They also generate a huge quantity of spend acids and alkalis that is difficult or impossible to recover.

At the Zhejiang Gongshang University in Hangzhou, researchers Ping Zhu and colleagues have developed a simple process of separation. They claim this process can recover valuable materials from waste PCBs at much lower recycling costs. At the same time, their method does not create the environmental pollution that other methods do.

Traditional methods decompose the polymer resins of waste PCBs to separate them. This process generates polybrominated dibenzofurans and deibenzodioxins, which are highly toxic. The new method is simple and easy as it swells the polymer resins, but does not allow it to decompose into the solution. Therefore, the process does not cause secondary pollution and the solvent can be reused.

According to the team, the process begins with stripping the waste PCBs of all electronic components. Next, the bare boards are shredded into fragments of approximately 1-3cm2. Then, the fragments are heated with DMSO – under an atmosphere of nitrogen. As the DMSO swells the brominated epoxy resin that holds the PCB layers together, they separate from one another. After abstracting and filtering the solution, it is evaporated under vacuum to regenerate the used DMSO. That leaves behind the separated polymer resin and the circuit board components.

At present, the size of the PCB fragments can be an issue in scaling the process up to industrial scales. At Ecyclex, an e-waste management company in the UAE, Saeed Nusri, a chemical engineer feels that this process could be remarkable. In his opinion, the process can solve many issues related to process complexity and solvent recovery that are typically faced in hydrometallurgical recycling of PCBs. Since only 2% of DMSO is lost in every run, there is a lot of savings in raw materials.

Make an inexpensive & simple UV LED Torch

UV LEDFrom our friends at instructables comes an easy project for use with UV LEDS.

To make this simple project, here’s what you’ll need:
2 Ultra Violet LEDS
1 1/4W resistors (the value of the resistor needs to be calculated based on the forward voltage of the LED you use)
1 non-working 9V battery (or a 9V battery clip)
1 new 9V battery
Soldering equipment

The full instructions on the Instructables site will show you how to put everything together. Once assembled, the light snaps on to a working 9V battery to function.

Keep in mind, you don’t have to use UV LEDS for this project – you can use any color. Just adjust the resistor required based on the forward voltage and forward current of the LEDS you choose.

Buying LEDS without specs or you don’t remember the specs of the ones you have sitting around? Assume a max of 2.8V – 3V and 20mA. I would think high intensity white LEDS would work really well for this project.

I haven’t put this one together myself yet, but I think a few of these are coming with me on my next camping trip. Nice way to light up the tent and the ‘facilities’ late at night. Fun project – and you probably already have everything you need right on hand.

What Happens to Old Electronic Components and Boards?

We came across this blog post the other day and thought it was worth bringing here.

Here’s an excerpt:

Yesterday I had the opportunity to shoot video in a facility that is the largest company in America that recycles the glass from electronics and computers. The men who own this company, built the machines that separate and break up the glass, themselves.

Electronic products and computers are torn apart. The plastics are sold to one vendor while the electronics and circuit boards are sold to another. The glass fragments are then shipped to companies that melt it down and produce new glass.

I was impressed by how much of the material is able to find new life, rather than to be dumped into a landfill where it would simply sit for all time.

I hope that he’ll update his blog when this segment is aired – I’d love to see the whole process!