Fuel out of Thin Air?

It’s not just hot air nor is it  some great Indian Rope trick! Rather it’s a great British Hope trick! Yes, recently a company based in UK (Air Fuel Synthesis) reported a break-through in converting thin air into fuel.  Since it sounds rather bizarre and incredible, I must clear the air.  So let us get into some details.

As you know air contains good amount  of carbon dioxide and some moisture besides , of course, oxygen & nitrogen. Here are the steps to produce fuel:

#1: Pass air containing carbon dioxide through a tower of  Sodium hydroxide solution to make Sodium carbonate. This will release carbon dioxide on electrolysis

#2: Use a dehumidifier to separate water from air

#3: Split water by electrolysis to get Hydrogen

#4: React Carbon dioxide & Hydrogen with a catalyst at a high temperature to produce Methanol

#5: React Methanol in presence of Special Catalysts to produce Gasoline/Diesel etc

All the 5 technologies are well- known & established individually. What is the big deal then? The innovation lies in combining all known technologies in a cost- effective manner to produce fuel.The unresolved question is how does one carry out the critical step#3 to produce hydrogen? Where does one get power to electrolyze and split water? The answer is : use renewable power such as solar or wind power. The entire process is technically viable and the company claims to have produced 5 litres of gasoline in the lab scale.

Apparently the UK company is looking for investors to prove their technology at a scale of  1 ton per day. Potential investors have to find answers to several questions to establish commercial viability. If it works as the company claims, it will solve several problems including Global warming. It can’t be simpler than this. Take Carbon dioxide from the atmosphere, convert to fuel and burn the fuel to produce Carbon dioxide back again. What a ‘carbon neutral’ virtuous cycle!

As the price of Crude oil is skyrocketing, Energy is the hot topic of research all over the world. People are talking about energy from municipal & domestic waste , from waste plastics & tyres, bio-masses like cellulose, Algae etc. In such a scenario there are bound to be both real & false claims and it is up to the investors to differentiate the real winners from the false.

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Published in: on October 28, 2012 at 2:33 pm  Leave a Comment  

Eco-friendly Plastics – Some developments

All of us know that 99% of the plastics(polyethylene, polypropylene,PET and PVC)) used today are made from fossil fuels. We also know(thanks to all negative publicity) that these plastics are not biodegradable – meaning that the polymer waste after use will remain for centuries without degradation and cause tremendous pollution to our natural resources and to all forms of life(human, animals,marine life etc).
This is the background in which quite a lot of research and technological efforts are being carried out today to come up with solutions to the problem. Isn’t it ironical that the problem was, in the first place created by the scientists or Technologists and now the very same community of scientists are being called upon to find a solution?
One could argue,though,that scientists are only a small link in the chain of events and very often they have very little say in the Science and Technology policies framed by Governments.
Anyway,the purpose of this article is only to briefly highlight certain important scientific and technological efforts that have taken place in the recent past in this field.
Scientists have approached the problem of making plastics eco-friendly by the following broad approaches:
1. Synthesizing biodegradable plastics from natural resources or synthetic materials or a combination of both.

2.Chemically transforming the used commodity plastics into useful fuels.

3.Converting the existing commodity plastics like polyethylene or polypropylene or PVC into biodegradable plastics by incorporation of certain additives / photo-catalysts.

The third approach is still being experimented upon in several laboratories. Therefore I will give a brief account of the first two approaches only here.

The multinational Chemical company (Zeneca) was the first to come up with an elegant solution with a smart piece of chemistry. They invented a polymer called “Biopol”(technically known as ‘polyhydroxybutyrate – valerate’). This is a a polymer built or assembled by certain bacteria and it has excellent film properties similar to our well known Polypropylene. Films,foils,dishes could be made out of it which would degrade within a few months of use and disposal. The original cost of this polymer was prohibitively high at 16 USD/ kg compared to Polypropylene at 0.5 USD. Improvements in technology like genetic engineering,better fermentation and purification technologies brought it down to 4-5 USD,which is still high in comparison to Polypropylene. Due to its high cost it has not come into general use.

Scientists followed another approach to make environment friendly polymers. These are based on a combination of natural and synthetic polymer systems. Following examples illustrate this approach:
1.Polymers based on Corn Starch:
Corn starch was gelatinized(high shear mixing to break crystallinity)and plasticised(admixed with glycerine) to make shopping bags,bread bags,over-wrap,flushable sanitary backing material etc. The cost of the product ,however,is higher than the conventional Polyethylene. In-spite of its higher cost,it has really caught on well in developed countries(Europe,USA and Australia etc). One Australian company has recently licensed this process to a Chandighar based company in India.
2.Starch based polymers are also made in the form of foam to substitute thermocol(technically known as ‘polystyrene’) for loose fill applications.
3. Yet another innovative development reports blends of Starch based polymers with polyesters based on lactic acid (polylactic acid -PLA). These are being used for high quality packaging applications.

While such efforts are continuing,I am quite impressed with certain amazing developments with a totally different approach which should partially mitigate the problem of biodegradability of commodity plastics like polyethylene and polypropylene . I will elaborate the same in some detail below.

Plastic waste transformation to liquid and gaseous fuels:
In this approach scientists have developed a process known as “Pyrolysis” would breakdown polypropylene or polyethylene into useful liquid and gaseous fuels. The conventional pyrolysis process is improved upon by using Catalysts for better and selective conversion efficiencies. Briefly the process has the following features:
1.Plastics are collected by Municipal authorities along with other household waste and segregated.
2.All plastics (PVC,Polyethylene,Polypropylene,Polyester or PET bottles etc) can be mixed together for this technology and there is no need to segregate different plastics which is labor intensive and costly.
3. They are melted and pyrolysed at a high temperature
4. Liquid and gaseous fuels are collected separately
5. Liquid obtained in the process is close to the composition of Diesel and fuel oil used in the industries as fuel, while the gas is close to LPG in composition. Therefore the entire product of pyrolysis is readily usable.
6. Most importantly the conversion of plastics is close to 99% and it has been proven to be economically viable.
7.The fuels produced in the process have also been successfully used to produce electricity.

The last feature gives me an idea that this technology can be used for rural electrification. The only hitch is that more than 95% of the plastics are consumed in the urban areas and therefore Government subsidies may be needed to cover the transportation costs to make it economically viable.

Solar Power and its utilization

Another exciting field for alternate energy source is the well known solar energy.
The principle of solar cells basically involves conversion of solar energy into electricity using certain semiconductors as cells or panels,which are technically known as ‘Photovoltaic cells’. The generated electricity can then be either stored in a battery for use later or transferred to an electric grid nearby.
The 1st generation cells were made up of single junction silicon crystals. While the efficiencies are very good ( I mean the efficiency of conversion of sunlight)the production costs are very high as it is highly labor intensive.
The second generation cells reduced the cost of manufacture significantly by using different materials and techniques (thin films of cadmium telluride for instance). Although the efficiencies were lower,the overall cost per watt came down from 1USD to 0.5 USD due to significantly lower cost of manufacturing . This enabled mass manufacturing of these cells.The process does not involve much labor either unlike the 1st generation solar cells.
However,looking at competitiveness with fossil fuels ,as on date only ‘dye-sensitized cells’ are competitive. However there are some technical issues with the long-term stability of the dyes.
Main areas of research in solar cells are centered around new types of efficient semiconductor systems capable of converting light into electricity with better efficiencies at lower cost of manufacture.

Innovations in applications are also taking place simutaneously. I would like to mention a couple of interesting applications here:

1.Rural electrification:
In a very innovative application development a team, working in Nicarugua and Venezuela, stitched-in flexible solar kits into a fabric which were worn during the day by men / women working in the hot sun. The electricity generated and stored could be used in the night to light bulbs. Besides the flexible thin film of of photo-voltaic cell(10 inch by 4 inch),the solar kit consisted of an LED and a rechargeable battery. (LED is an electronic device which converts electricity into light).
The project provides a way for the local communities to have bright light inside their homes at night and recharge the power under the sun during the day. And the power can be used to charge cell phones and medical devices as well. Most importantly the entire kit is light weight and can be customized to be incorporated into existing materials of textile fabric. The batteries can be charged in 2.5 hours and give light for 10 hours. The light output per watt is much better than that of a conventional 100 watt bulb.
In another related application,the team is also working on the use of portable light to generate UV light emitting LED,which can be used for purification of water in rural areas.

2.A variation of the same concept for urban areas consisted of solar cells incorporated into venetian blinds exposed to sunlight. The electricity generated is stored in a battery and used in the nights.

3. One hears of cell phones being charged by solar cells and car roofs being fitted with solar panels with the stored energy being used to run car air-conditioners.

Published in: on March 19, 2009 at 5:19 pm  Leave a Comment  
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Algae as a source of Biofuel

In the previous post I wrote about alcohol as a fuel from Cellulose in the plant(often referred to as Cellulosic Ethanol).
The next field of green technology which is also expected to bring about a big transformation in energy security is the conversion of Algae to vegetable oil and biodiesel.
What is algae? In simple terms it is just an open pond scum. Technically,it is a fast growing single celled organism. And the organism can use atmospheric carbon dioxide and sunlight(in presence of nutrients)to sugar,oil,proteins and oil. The facts that make it an attractive source of future fuel are very compelling if one considers the following:
-Only 2.5kg of algae needed to produce 1 kg of oil
-30 times more energy per acre is generated compared to any conventional vegetable oil seed like corn,palm or rapeseed oil
– can grow 20 times faster than the conventional oil seeds.
– They do not affect fresh water resources
– Can be produced using ocean and waste water.
– They are biodegradable and therefore harmless to the environment if spilled.
On the flip side,the difficult part is growing algae in a controlled and efficient manner to produce vegetable oils with high selectivity. Seeking to find solutions to this problem,very interesting ‘cutting edge research’ using genomic and proteomic technologies is being carried out to understand molecular switches responsible for enhanced oil production.

One finds quite a lot of innovative research publications in basic science and technology of utilization of Algae to make bio-fuel. I will mention here only one example of an interesting research which will be of great value in the near future. At MIT,under the leadership of Prof Isaac Berzin,a very innovative and almost revolutionary concept was developed.The idea of Prof Berzin is amazingly simple. Carbon dioxide from a power plant at MIT was bubbled through an algae soup exposed to sunlight. The algae soup absorbs close to 80% of Carbon dioxide and converts it into vegetable oil,which can be easily transformed to Biodiesel. If commercialed,this will mitigate both problems in one shot – that is the energy problem and the and green house gas emission problem which is the cause of global warming.(All of us are aware that increasing levels of Carbon dioxide emission is responsible for global warming).
Today USA is leading from the front in developing these technologies and have set themselves an ambitious target to substitute 20% of gasoline with biodiesel made from algae by 2017. And this goal seems perfectly achievable given the kind of push the project is receiving through Federal grants as well as partnerships with private enterprises.
I am sure the coming decade will be highly exciting in terms of scientific and technological landmarks in the energy sector.

In the next post I will describe certain interesting developments in the field of Solar Power.

Published in: on March 19, 2009 at 2:26 am  Comments (1)  
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Alcohol from Cellulose – A Green Fuel Option

In my recent article on economic downturn I wrote about the stimulus package and the type of projects on which it needs to be used. One of the options I mentioned was the so called green technologies. Here I would like to elaborate a little bit on certain specific areas of green technology requiring funding and attention. The list I have made is only partial. I must also add that the material that follows is strictly meant for the laymen.
All of us will agree that the most important project category requiring huge funding is related to renewable energy source. More specifically,the following technologies could make a very big impact in the coming years when successful:
1.Cellulosic ethanol
2.Algae based Biodiesel
3.Making Solar energy cheaper and making innovative use of solar panels in a way useful to rural and urban electrification
4.Wind energy
5.Energy efficient gadgets/bulbs, making LED cheaper
6.Biodegradable Substitutes for polyethylene / polypropylene
7.Conversion of plastic wastes to liquid / gas fuels
8.Green house gas emission control technologies
9.Biotechnology as a tool for replacing conventional chemical process technologies

Today almost all the above fields are hot areas of research in industries as well as universities the world over.
I will deal with a few of the above areas briefly in the following posts,starting with Cellulosic ethanol in the present article.

Cellulosic ethanol (that is fuel grade ethanol from cellulose) projects are being pursued in the USA like Manhattan Project with a lot of federal funding and through public-private partnerships. $1 billion has been committed and it has been doubled in the recent past. An institute(Energy bioscience institute)was setup at at the university of California(Berkely) with a clear mandate to manage the switch over from corn based ethanol (I will explain later in this article why the switch over is essential) to cellulose based ethanol in 10 years.

What is cellulose? Cellulose constitutes 70% of most of the plants and is present in wood,grass,stem etc. Entire cellulose is non-edible for human consumption.
Briefly,the project involves the use of cellulose as a source for making ethanol. Ethanol is a proven fuel which generates the least amount of pollution(both gaseous and particulate)when burnt in an automotive engine. Today processes exist but are not cost competitive with conventional gasoline(the cost is around $4/barrel versus 1.3 for gasoline). Some plants are already operating although not on big commercial scale. Most of the work is focused on reducing the cost.
The basic issues of technology are:
1.Finding a suitable efficient enzymatic process to breakdown cellulose to glucose
2.Reducing overall cost through innovations in engineering / scale-up.
While hectic research activity is in progress to sort out scientific/technology issues,at least 2 companies have reported commercial plant operations – one is the Ottawa based Iogen and the other is Lousiana based Verenium.

In view of the above developments,my personal view is that we should forthwith stop spending on research,technology and commercial production for converting corn to ethanol.
All of us are familiar with ‘food versus fuel debates’ an year ago when the USA was actively pursuing corn based ethanol projects on a very large scale. While cellulose process uses 70% of the plant(stem,grass,wood),’Corn to ethanol’ process uses only the seed. Obviously,therefore, the latter process would require a lot more agricultural land.
There is yet another disadvantage of the ‘corn to ethanol’ process. The process is not carbon neutral,meaning that there is net carbon dioxide(global warming gas) generation in the process. The main reason for this is that one needs to burn natural gas for distillation(purification) of alcohol formed. In contrast, in the process involving cellulose, the residue left after enzymatic hydrolysis can be used as fuel for distillation of alcohol.

In my next post I will deal with Algae as the source of Biofuel.

Published in: on March 17, 2009 at 6:46 pm  Leave a Comment  
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