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Category Archives: Electrolysis

We have used Hydrocarbon as the source of fuel for our power generation and transportation since industrial revolution. It has resulted in increasing level of man-made Carbon into the atmosphere; and according to the scientists, the level of carbon has reached an unsustainable level and any further emission into the atmosphere will bring catastrophic consequences by way of climate change. We have already saw many natural disasters in a short of span of time. Though there is no direct link established between carbon level in the atmosphere and the global warming, there is certainly enough evidence towards increase in the frequency of natural disasters and increase in the global and ocean temeperatures.We have also seen that Hydrogen is a potential candidate as a source of future energy that can effectively substitute hydrocarbons such as Naphtha or Gasoline. However, hydrogen generation from water using electrolysis is energy intensive and the source of such energy can come only from a renewable source such as solar and wind. Another issue with electrolysis of water for Hydrogen generation is the quality of water used. The quality of water used for electrolysis is high, meeting ASTM Type I Deionized Water preferred, < 0.1 micro Siemen/cm (> 10 megOhm-cm).

A unique desalination technology has been developed by an Australian company to generate on site Hydrogen directly from seawater. In conventional seawater desalination technology using reverse osmosis process only 30-40% of fresh water is recovered as potable water with TDS less than 500 ppm as per WHO standard. The balance highly saline concentrate with TDS above 65,000 ppm is discharged back into the sea which is detrimental to the ocean’s marine life. More and more sweater desalination plants are set up all over the world to mitigate drinking water shortage. This conventional desalination is not only highly inefficient but also causes enormous damage to the marine environment.

The technology developed by the above company will be able to recover almost 75% of fresh water from seawater and also able to convert the concentrate into Caustic soda lye with Hydrogen and Chlorine as by-products by electrolysis. The discharge into the sea is drastically reduced to less than 20% with no toxic chemicals. This technology has a potential to revolutionize the salt and caustic soda industries in the future. Caustic soda is a key raw material for a number of chemical industries including PVC.Conventionally, Caustic soda plants all over the world depends on solar salt for their production of Caustic soda.Hydrogne and Chlorine are by-products.Chlrine is used for the production of PVC (poly vinyl chloride) and Hydrogen is used as a fuel.

In the newly developed technology, the seawater is not only purified from other contaminants such as Calcium, Magnesium and Sulfate ions present in the seawater but also concentrate the seawater almost to a saturation point so that it can be readily used to generate Hydrogen on site. The process is very efficient and commercially attractive because it can recover four valuable products namely, drinking water, Caustic soda lye, Chlorine and Hydrogen. The generated Hydrogen can be used directly in a Fuel cell to generate power to run the electrolysis. This process is very ideal for Caustic soda plants that are now located on seashore. This process can solve drinking water problems around the world because potable water becomes an industrial product. The concentrated seawater can also be converted in a salt by crystallization for food and pharmaceutical applications. There is a growing gap between supply and demand of salt production and most of the chemical industries are depending upon the salt from solar pans.

Another potential advantage with this technology is to use wind power to desalinate the water. Both wind power and Hydrogen will form a clean energy mix. It is a win situation for both water industry and the environment as well as for the salt and chemical industries. In conventional salt production, thousands of hectares of land are used to produce few hundred tons of low quality salt with a year-long production schedule. There is a mis match between the demand for salt by large Caustic soda plants and supply from primitive methods of solar production by solar evaporation contaminating cultivable lands.

The above case is an example of how clean energy technologies can change water, salt and chemical industries and also generate clean power economically, competing with centralized power plants fuelled with hydrocarbons. Innovative technologies can solve problems of water shortage, greenhouse gases, global warming, and environmental pollution not only economically but also environmental friendly way. Industries involved in seawater desalination, salt production, chemical industries such as Caustic soda, Soda ash and PVC interested to learn more on this new technology can write directly to this blog address for further information.

Nature has a wonderful way of capturing Carbon and recycling it through a process called ‘carbon cycle’ for millions of years. The greenhouse gases in the atmosphere were restricted  within certain limits when it was left to Nature. But when human being started burning fossil fuels to generate power or to run cars, the GHG emission surpassed the limit beyond a point where global warming became an issue. The GHG level has increased to 392 ppm level for the first in our long history. Many Governments and companies are exploring various ways and means to reduce greenhouse emissions to avoid global warming. Some Governments are imposing taxes on carbon emission in order to reduce or discourage such emissions. Others are offering incentives to promote alternative energy sources such as wind and solar. Some companies are trying to capture Carbon emission for sequestration.

While we try to capture Carbon and store them underground, there are many potential commercial opportunities to recycle them. This means the Carbon emission is captured and converted into a commercial fuel such as Gasoline or Diesel or Methane so that future sources of fossil fuels are not burnt anymore. But this is possible only by using ‘Renewable Hydrogen’. Hydrogen is the key  to reduce carbon emission by binding carbon molecules with Hydrogen molecule, similar to what Nature does.

When NASA plans to send a man to Mars they have to overcome certain basic issues. Mars has an atmosphere with 95% Carbon dioxide, 3% Nitrogen, 1.6% Argon and traces of oxygen, water and methane.Nasa is planning to use Carbon dioxide to generate Methane gas to be used as a fuel and also generate water by using the following reaction.

CO2 + 4H2—–CH4 + 2 H2O

2H2O——-2H2 + O2

The water is electrolyzed to split water into Hydrogen and Oxygen using solar power. The resulting Hydrogen is reacted with Carbon dioxide from Mars to generate Methane gas and water using a solid catalyst. This methanation reaction is exothermic and self sustaining. How this can be achieved practically in Mars in those conditions are not discussed here. But this is a classical example on how the Carbon emission can be tackled to our advantages, without increasing the emissions into the atmosphere. There are several methods available to convert Carbon emission in to valuable products including gasoline. The  reaction of the methane with water vapor will result in Methanol.

2H2 + CO——– CH3OH

On Dehydration, 2CH3OH —– CH3COCH3 + H2O.Further dehydration with ZSM-5 Catalyst gives Gasoline 80% C5+ Hydrocarbon. Gas to liquid by Fischer-tropic reaction is a known process.

Carbon dioxide is also a potential refrigerant to substitute CFC refrigerants that causes Ozone depletion. Carbon recycling is a temporary solution to mitigate Greenhouse gas emission till Hydrogen becomes an affordable fuel of the future. It depends upon individual Governments and their policies to make Hydrogen affordable. Technologies are available and only a political will and leadership can make Hydrogen a reality.

Stanley Meyer, a freelance inventor from USA demonstrated a car that ran on water, according to an Equinox programme that was televised in 1995. Stane Meyer’s dune buggy ran 100 miles from 1 gallon of water. He claimed that water would be the fuel that could revolutionize the auto industry in America. However, his tragic death in 1998 brought the issue to a closure.  Many people and institutions are still trying to replicate his invention at least partly and claiming success.  He received a   number of patents based on his inventions. He worked nearly 30 years on his invention before he began to work on a book titled, “With the Lord, there is a purpose” describing his “faith walk” with the Lord to fulfill end-time Prophecy.  He continued with his speaking engagements throughout the world.  However, such ‘free energy’ devices are still not getting the approval of the larger scientific community as well as Government agencies for some reasons or other. According to Stanley Meyer, “the law of Physics establishes a proven function based on ‘Pre-set’ conditions…change any of the conditions and the Law no longer applies….A new law emerges in the consciousness of physics. Why? Because atoms possess intelligence—-Performing ‘what if’ logic function under different ‘preset’ conditions.” His claims were based on scientific principles and explanations.  Based on his invention, many of ‘Electrolyzing devices’ appeared in the market.  They supply Do It Yourself  kits that can be fitted into a car to cut Gasoline consumptions; but they do not entirely  substitute Gasoline like Stanley Meyer demonstrated. There are still missing pieces of information or claims. He was able to show and claim “Hydrogen fracturing process to disassociate water molecules by way of voltage simulation, ionization of combustible gases by electron ejection and then preventing the water formation during thermal ignition releasing a thermal explosive energy beyond ‘normal gas burns’ levels under control state… and such an atomic energy process is environmentally safe”.   He did not use ‘Heavy water’ called ‘Deuterium’ but normal water and controlled state and shown that the covalent bond of water can be broken using an electronic circuit using water as dielectric medium of a capacitor.  It uses a high voltage but a low current and the process is instantaneous.  It differs from the ‘Faraday’s law of electrolysis’ in a conventional sense. The scientific community seems to be a little more understanding with an open mind in recent times to such ‘free energy’ concepts and devices than in the past.  ‘Resonance electrolysis’ has been reported by few institutions and people as an alternative to ‘conventional water electrolysis’ to cut energy consumption. Decomposition of water into its molecules requires high temperature above 3000°C using a process known as ‘pyrolyis’ and a technique to separate the decomposed molecules from reunion for water formation.  Prof. Mizuna of Hokkaido University of Japan and his coworkers demonstrated ‘Plasma Electrolysis’ by an experiment which showed an evolution of anomalous amount of Hydrogen and oxygen sometimes as much as 80 times more than normal Faraday’s electrolysis of gas generation. Though such reaction requires a very high temperature they could not successfully measure the reaction temperatures during the experiments. They used a Platinum anode and Tungsten cathode and a provision to separate Hydrogen and oxygen gases. They concluded at the end of the experiment that the input voltage and the current efficiency were critical parameters.  On increasing the Voltage to several thousands, they said the current efficiency can exceed unity.  The anomalous release of gases indicates that the electrolysis is not a normal electrolysis but beyond that. (Ref:Mizuno, T., T. Akimoto, and T. Ohmori. Confirmation of anomalous hydrogen generation by plasma electrolysis. in 4th Meeting of Japan CF Research Society. 2003. Iwate, Japan: Iwate University) In all these experiments the gases coming out of the system are not at high temperature but at normal room temperature.  The chemistry of water molecule decomposition and plasma pyrolysis is not fully understood.  After all ‘Cold fusion’ seems to be plausible under certain conditions and it may be a panacea for the world’s energy problems.  When our energy requirement exceeds a limit due to a population explosion and industrialization then finding a solution becomes a daunting task. Mohandas Gandhi said: “There is enough for everybody’s need but not for everybody’s greed. Be the change what you wish to see in the world”.

It is amazing that highly combustible Hydrogen is a constituent of cool water. As long as it remains a part of a water molecule we are able to handle it easily. Water is always in a state of ionization with H+ and OH- ions in a dynamic equilibrium. The electrical conductivity of pure water which is completely free from any other ions is almost zero. In a solid polymer electrolyzer, which is the reverse of Fuel cell, water is decomposed into Hydrogen and Oxygen while passing a Direct current. Electrolyzer is an electrolytic cell similar to battery, containing an Anode, Cathode and Electrolyte. In a solid polymer Electrolyzer, the electrolyte is a polymer membrane. Water is decomposed as shown in the following reaction:

At Anode of electrolyzer:               H2O——– 0.5 O2 + 2e + 2H†

At Cathode of electrolyzer:             2H† + 2e —— H2

The purity of water is critical in the above process of electrolysis. In conventional electrolysis, water with addition of potash lye (KOH) acts as an electrolyte. But in the above process there is no need for any addition of lye. Moreover, Hydrogen can be generated at high pressure so that further compression becomes easier. In cases of power generation using Fuel cell, the Hydrogen pressure from Electrolyzer is sufficiently high, obviating the usage of an additional compressor.

The electrical conductivity of water increases as the concentration of dissolved salts increases. That is why the electrical conductivity of seawater is much higher than your tapwater.But this salt can be removed by the process of desalination using ‘reverse osmosis’ systems.

When you separate pure water and salt water using a semi permeable membrane there is natural tendency for pure water to pass across the membrane to pure water side. This process is called ‘Osmosis’. The process continues till the concentration of water on both side of the membrane becomes equal. Nature does not like disparities between strong and weak and always tend to make both equal. By reversing this principle of osmosis, we can separate salt water into pure water and highly concentrated salt water known as brine. This process is called ‘Reverse osmosis’. We will discuss about this process later.

If your tap water is not very hard, say such as, total dissolved solids TDS is around  500ppm (Part per million), then the osmotic pressure is not high, which means you do not need to use a high pressure pump. Higher the TDS level, higher the osmotic pressure and higher the power consumption will be. You can install a reverse osmosis system based on your water analysis. You have to use a pure water with low conductivity 10-15 micro Siemens/cm.The reverse osmosis system can be connected to your tap and  store pure water while draining the salt water into the drain. You can use this pure water to an Electrolyzer to generate Hydrogen. The Hydrogen can be stored in a tank made up of Carbon composite materials that can withstand high pressure and approved by regulatory authorities.

This article is only to understand how Hydrogen can be generated using your tap water. The actual implementation of the system requires knowledge and experience in installing such a system. But we will release an eBook, a step by step guide to set up your power generation system as well fuelling your Fuel cell car, using Hydrogen. An independent power generation and fuelling system using only solar power and water will soon become a commercial reality because, it is a clean and sustainable solution for all our energy problems. The PV solar industries are already expanding at a faster rate and solar Hydrogen will soon become a final solution.

In a Regenerative fuel cell the results of redox reaction between Hydrogen and Oxygen, are power and water; the above reaction can be reversed in the same electrochemical process to regenerate hydrogen and oxygen. Such a system is called ‘regenerative fuel cell’. It is a perfect example of a closed circuit system. In ancient Hindu mythology there were citations that claim water came from fire and fire came from water. Two gaseous elements Hydrogen and oxygen reacts violently rather explosively resulting in cool water. Perhaps Hindu mythology terms this reaction as fire which results in water. Similarly by passing a direct current into water, it splits water into oxygen and regenerates Hydrogen, which is a symbolic representation of Fire. Many would have watched a number of ‘you tube videos footings’ on water gas. The water gas or Brown’s gas is a mixture of Hydrogen and oxygen along with un-dissociated water molecules liberated during the process of electrolysis. It can be lit into a flame similar to Oxy-acetylene flame and can be used even to cut metal plates. That is the power of brown’s gas, which I call Oxy-Hydrogen gas. This torch is commercially marketed for metal cuttings applications. But production of pure Hydrogen completely free from Oxygen is a matter of great commercial importance.

Hydrogen is one of the lightest gases and it has a strong bondage with noble metals like Platinum and Palladium. Platinum  catalyst with carbon as a carrier has a wider industrial applications such as hydrogenation in fine chemicals and pharmaceuticals. The author has experience in such applications in bulk drug manufacturing such as Ephedrine and Paracetamol. In a PEM (Proton exchange membrane fuel cell) MEA (membrane electrode assembly) is the heart. The Platinum catalyst coated on the surface of the ‘Nafion’ membrane reacts with gaseous Hydrogen gas. It strips the electron from hydrogen atom while the polymer membrane allows only proton to pass through. The expelled electron flows around the circuit. Flow of electron is nothing but current or electricity. The proton crosses the membrane and reacts with incoming Oxygen through cathode forming water. It is an exothermic reaction and generates heat similar to any combustion reaction, that has to be dissipated.In larger installation we can use this waste heat for a typical CHP (combined heat and power applications) such as power and steam or chilled water or for space cooling. Fuel cell (based on Hydrogen fuel) operates quietly with absolutely no emission except water, and of course, there is no smoke. It is an ideal power source for 24×7 applications such as hospitals, call centers, departmental stores and continues process industries.

In the reverse process of a Fuel cell, the electrochemical device becomes an Electrolyzer splitting water into Hydrogen and oxygen. The electrolyzer works the same way as Fuel cell except in reverse direction; feed is de-ionized water and the products are Hydrogen and Oxygen. In bipolar alkaline electrolyzer, a catalyst such as potash lye is added where in solid polymer electrolyzers platinum acts as a catalyst like a Fuelcell. The generated Hydrogen comes under pressure obviating the use of an extra compressor. The Hydrogen is stored in cylinders for further usage.

As I mentioned in my previous articles the power required to split water into Hydrogen and Oxygen is more than the power generated from the resulting Hydrogen by a Fuelcell.That means an input of excess energy is necessary for a regenerative fuel cell to run successfully .Where this energy will come from depends on the cost benefit analysis to be made. Surplus Hydro power is ideal for such regenerative fuel cell applications. But we can also use various other renewable energy sources such as wind, solar, geothermal, OTEC depending upon the site and applications. The biggest advantage with regenerative fuel cell is there is no other input except the excess power to be supplied. When renewable energy is deployed on large commercial scales then regenerative fuel cell will become a clean solution of the future. I have no doubt in my mind that this will become a commercial reality. Of course the top policy makers should understand the potential and make a right decision and encourage more business and industries to deploy such systems. The energy costing model cannot be based on fossil fuel model because fossil fuel is not renewable. This is the crux of the problem.

In our future articles we will present case studies of various clean energy systems that are already in commercial operation. I also welcome articles from clean energy professionals with life project experience and problems they face. I welcome comments and feedback from business, industries and people.

Seawater is an inexhaustible source of Hydrogen but the cost of generating Hydrogen from seawater is much higher compared to normal tap water. The quality of water should have a minimum electric conductivity at 0.1 micro Siemens/cm for electrolysis. Even our tap water is not up to this purity and it requires further purification. The electric conductivity of seawater is about 54,000 micro Siemens/cm.The conductivity increases due to the presence of dissolved salts. But seawater can be desalinated using the process of distillation or by the process called ‘reverse osmosis’. In both the above processes, desalination requires a large input of energy in the form of thermal or electrical. Currently the source of such energy comes from fossil fuels, which is one the biggest emitters of greenhouse gas emission. Many countries in the Middle East have shortage of fresh water and most of these countries depend on desalination of seawater for their fresh water requirements. The cost of desalinated water varies from $ 1.00 to $ 1.75/m3 depending upon the capacity, site and the cost of energy. The fresh water for potable purpose normally has a TDS (Total dissolved solids) of 500ppm (parts per million) or less and this can further be lowered to a required level using reverse osmosis.

Currently Hydrogen is generated as a by-product on an industrial scale by electrolysis of saturated sodium chloride brine during the production of Caustic soda. Chlorine is another by-product in the above process. Most of Caustic soda manufacturers use Hydrogen as a fuel or for the production of Hydrochloric acid. But there is an opportunity in caustic soda plants to use Hydrogen to generate more electricity using PEM (Proto exchange membrane) Fuel cell suitable for their electrolysis. This will aid these industries to cut their energy consumption, which is one of the highest in Chemical industries.

Alternatively, offshore wind turbines can be installed to generate power for seawater desalination and Hydrogen production. Offshore wind turbines generate 50% more energy than onshore wind turbines. An integrated process to generate fresh water, Hydrogen using wind turbine is an interesting renewable energy application. The stored Hydrogen can used to generate electricity in remote islands where diesel is used as a fuel. Most of the island in Pacific use diesel predominantly for boat as well as for power generators at exorbitant costs. The wind velocity in such islands is good to generate cheap and clean electricity. For example, the island of PNG has a severe power shortage and it is well located near Coral Sea, which has one of the highest wind velocities in Pacific Ocean. An average wind velocity of 7mts/sec and above is an ideal place for wind turbines. Since these islands are small with less population, wind generated Hydrogen is an ideal solution for their power problems. They can also desalinate seawater to supply drinking water using wind generated power. In fact they can also use Hydrogen as a fuel for their boats and generate power for their cold storage for fisheries. International financial institutions and local banks should come forward to fund such projects instead of funding diesel boats and generators. These islands have pristine water and abundant fish and their main income is only tourism.

Sun, Sand and wind is an ideal combination to generate renewable power all round the year and for tourism industry. It is an opportunity these islands cannot afford to miss. The author is personally involved in a wind based Hydrogen solution for a small island in pacific. The people of this island welcome such projects because it guarantees them an uninterrupted supply of clean power and drinking water. Otherwise they have to sell most of fish catches in a nearby city to buy diesel and drinking water just to survive!

 

 

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