Turning orange peel into plastic
BRITISH scientists are pioneering a novel way of recycling that turns orange peel into plastic. The technique relies on high-powered microwaves that can degrade the tough cellulose molecules of plant matter so that they release volatile gases that can be collected and distilled into a liquid product. These valuable biodegradable chemicals can then be used in water purifiers, cleaning agents and plastics.

THIS UNIVERSE 
I am a student of history even though I was a formal student of science till my 12th grade. I took a tough decision to take up history, because I was deeply interested in it. I am also interested in physics and chemistry. Why don’t we have the option of studying physics and history?
YOU have raised a question that is connected with a basic aberration of our system of education. We have had a tendency of limiting human learning within iron clad disciplines. This way we separated it from life and the wonderful manifestations and dimensions of knowing.

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Turning orange peel into plastic
Steve Connor

BRITISH scientists are pioneering a novel way of recycling that turns orange peel into plastic.

The technique relies on high-powered microwaves that can degrade the tough cellulose molecules of plant matter so that they release volatile gases that can be collected and distilled into a liquid product.

These valuable biodegradable chemicals can then be used in water purifiers, cleaning agents and plastics. Researchers behind the process say it is 90 per cent efficient and works not just on orange peel but almost any plant-based waste such as straw or coffee grounds.

James Clark, professor of green chemistry at the University of York, said he is building a small demonstrator facility to show the novel recycling scheme can be scaled up in order to suit industrial applications.

“It will be able to cope with tens of kilograms an hour. We believe it is the right scale to prove to people that this is a viable technology,” Professor Clark said.

“You dice the peel and put it into a microwave field. You then focus the microwaves as you would with a domestic microwave oven but at higher power,” he said.

“The microwaves activate the cellulose and that triggers the release of chemicals or further chemical reactions inside the orange peel,” he told the British Science Festival at Bradford University.

Volatile chemicals are released in the process, including d-limonene, which is responsible for the distinctive smell of citrus fruit and is used in cosmetics, the cleaning industry and as a biological insecticide.

“As you produce the volatiles you strip them off continuously. It’s a continuous process. You feed the peel into a microwave zone and have a pipe that takes off the volatile fractions as they are produced,” he said

“The unique feature of our microwave is that we work at deliberately low temperatures. We never go above 200C. You can take the limonene off or you can turn limonene into other chemicals,” he said. “It works really well with waste paper. It can take a big range of bio-waste material.”

York University has set up the Orange Peel Exploitation Company with Brazilian and Spanish partners to test the idea of using orange peel residue left behind from the juice-making industry in the two countries.

“There are eight million tonnes of orange residue in Brazil. For every orange that’s squeezed to make juice, about half of it is wasted. What we’ve discovered is that you can release the chemical and energy potential of orange peel using microwaves,” Professor Clark said.

“Orange peel is an excellent example of a wasted resource. Brazil is the largest producer of orange juice in the world,” he said.

The idea is to take the technology to places where large amounts of plant waste are already collected, such as a power stations that collect biomass for burning or a farming district that packs or processes foodstuffs, Professor Clark said.

“We are talking to farmers who are already concentrating a lot of biomass for palletising before going to power stations about the possibility of locating a facility in one of these centralised units,” he said.

“We’re talking to power stations about materials that they are already bringing in for microwaving as well. If you put typical waste into our system before you burn it, the calorific value doubles compared to what it was before,” Professor Clark told the meeting. — The Independent

THIS UNIVERSE 
PROF YASH PAL

I am a student of history even though I was a formal student of science till my 12th grade. I took a tough decision to take up history, because I was deeply interested in it. I am also interested in physics and chemistry. Why don’t we have the option of studying physics and history? 

YOU have raised a question that is connected with a basic aberration of our system of education. We have had a tendency of limiting human learning within iron clad disciplines. This way we separated it from life and the wonderful manifestations and dimensions of knowing.

Learning only one or two disciplines and nothing outside is cruel limitation of human capability. Beautiful new things always emerge close to boundaries of disciplines. In 1993, I was invited by All-India Institute of Medical of Medical Sciences to give a special oration. The topic I chose was: “Why must we remain so utterly cubicalised?”

I recently came across my in one of my old notebooks the lecture notes I had prepared for that lectures. In that lecture I explained in detail how a psychiatrist pursued his urge to develop a technique for imaging the central nervous system. I explained how this man pursued his passion vigorously using wide ranging interaction with physiologists, biologists, neuroscientists, biochemists, historians of ideas, chemists, radio chemists, nuclear physicists and engineers. None of these others could have themselves invented what he finally managed to produce. The technique is known as PET (Positron Emission Tomography). This happened because a man wanted to find a way of finding a way of learning, what after all happens in our brain when we think.

I was able to bring this adventure alive because I happened to meet this man. After recounting his effort I went on to say that most of the techniques this marvellous man had put together were known to me or my friends but we did not proceed the way he did because I and my friends never had an opportunity to sit across a table for a cup of coffee while sharing what we wondered about.

I asked the audience of very capable physicians and doctors how long would it take before they provided opportunities to their young people to do some thing like what that psychiatrist had done. The silence in the room indicated that such a situation was almost impossible because there were too many restrictions in allowing such people to get together. So long as we remain imprisoned in our disciplines we are unlikely to do entirely new things.

Recently, I have had an opportunity to explore the reasons for this insulation amongst our academics. We submitted a report on rejuvenation and renovation of higher education in which we strongly recommended movement across disciplines.

A student joining a college should be able to study history or other subjects in humanities along with physics and philosophy. Things have not moved in that direction. In fact large scale expansion of private institutes and deemed universities have destroyed the very idea of a university, which should be providing access to the universe of knowledge. Coming to your concern, remember that there is a long time ahead of you and you can cross all obstacles. There are many examples of that, including my own.