Water contaminated with heavy metals is an important environmental concern, especially due to the metals’ cumulative effect in organisms. Metal-organic frameworks (MOFs) are coordination networks of metal ions or clusters linked using organic ligands. The combined effects of the organic and inorganic moieties allow tuning the size of the pores and provide high surface area to mass ratios while ensuring that the material is chemically and structurally stable.
Dipak Rana and colleagues, University of Ottawa, Canada, have developed an efficient membrane containing MOFs that can efficiently remove Pb2+ and Hg2+ ions by filtration of contaminated water solutions. MOF 808, containing Zr6 clusters, and the Fe-based MOF-F300 were enmeshed in nanofibers of polyacrylonitrile (PAN) and polyvinylidene fluoride (PVDF).
The team concluded that the adsorption of the metals was due to a combination of competitive ion exchange, electrostatic interactions, and pore filling of the MOFs. Removal of Hg2+ and Pb2+ was achieved under controlled acid conditions. The experiments demonstrated that the total negative charge of the deprotonated COOH groups at the metal clusters drags the positive metal ions from the surface into the pore cavity. This was shown by a continuous decrease of the pH as the heavy metal ions promoted the release of protons.
- Metal-organic frameworks supported on nanofibers to remove heavy metals,
Johnson E. Efome, Dipak Rana, Takeshi Matsuura, Christopher Q. Lan,
J. Mater. Chem. A 2018.
https://doi.org/10.1039/c7ta10428f
Removal of heavy metal ions (like Hg2+ and Pb2+) from contaminated water with the membrane containing Fe(III) and Zr(IV) based metal-organic frameworks that enmeshed in polyacrylonitrile and polyvinylidene fluoride electro-spun nanofibers have successfully developed by Rana e tal. This filtration technique will be more useful than ion exchange, electrostatic interaction and other traditional methods. So, I have strongly recommended this adsorption technique to publish in daily newspapers to aware public.
Excellent piece of work from Rana and Matsuura research Group from the University of Ottawa.
The beauty of the work is the cumulative effect of competitive ion exchange, electrostatic interactions, and pore-filling of the MOFs for the removal of heavy metals. Utilizing different phenomenon and developing a hybrid system is a brilliant approach for the effective water treatment.
With increasing demand for clean water, no doubt in future clean water is going to be our next oil, and the demand for the easy, energy efficient and economic clean water technologies will only be a solution to fulfil this requirement for the increasing industrialization and world population.
Excellent piece of work!!!! Hats off to the Prof. Rana and Prof. Matsuura group for discovering this adsorption technique. They have discovered a new class of materials for removal of heavy metals form the contaminated drinking water. It is indeed a brilliant approach for the water treatment. Currently, the whole world is facing the water crisis challenge and this MOF membrane would be the next generation technology without any doubt.
Dr. Rana and his group have done a great work. Their discovery might be use full in textile effluent treatment., because textile effluent contains different types of heavy metals.
An excellent discovery of Nanofibrous MOF Membranes for removing heavy metals by Dipak Rana and Prof. Matsuura group. The group showed that a new class of MOF materials selectively adsorb heavy metal ions (Hg2+ and Pb2+) from the contaminated drinking water. It is an outstanding adsorption technique not only useful in clean water technology but also in other areas i.e., in the textile industry, wastewater treatment, manufacturing industry where the removal of these toxic metal ions remains a huge challenge.
From the perspective of the world-wide problem of safe drinking water due to contamination of groundwater by leached out heavy metals ions (HMIs), this innovative research is very welcomed. Human body needs some heavy metals like iron (e.g. hemoglobin, cytochrome), zinc (e.g. Zn finger proteins), copper (e.g. Cu proteins), manganese (e.g. Mn-dependent superoxide dismutase), cobalt (e.g. cobalamin, B12), molybdenum (Mo oxo transferase), etc., however, the toxicity increases when present in higher amount, for example exposure to mercuric salt could have toxicological effects on gastrointestinal tract and kidney, lead(II) has been demonstrated to cross blood-brain barrier that effects the central nervous system. The developed metal organic frameworks (MOFs) with nano-fibrous adsorbent has been found to a high absorption capacity of 53.1 mg/g (MOF-808) to 42.6 mg/g (F-300) for Hg+2, and 30.2 mg/g (MOF-808) to 17.2 mg/g (F-300) for Pb+2, respectively. Furthermore, the activated MOF-808 with nano-fibrous adsorbent has also been found to be a high absorption capacity of 43.9 mg/g for Cd+2 and 56.7 mg/g for Zn+2. Therefore, I sincerely believe the research will have a new contribution to the field of abatement of HMIs contamination problem of drinking water.
Accessibility of clean water is a basic human right. However, billions of people in the world do not have the access of potable water and they are forced to live by drinking unsafe water which causes them illness and life-threatening diseases. Among others, heavy metal (e.g., lead, mercury, arsenic, etc.) contamination is one of the major areas of water pollution. Therefore, a large number of scientists in all over world are focused on the development of methodologies and technologies for improved water purification systems. Very recently, Dr. Rana and co-workers (University of Ottawa) have reported an efficient method based on nanofibrous MOF material which can remove toxic metal ions like mercury and lead ions from non-drinkable aqueous solution, making it drinkable, clean water. The adsorption quality of the membrane is very high and even after four cycles of adsorption and desorption, still more than 90% adsorption quality of the nanofibrous MOF membrane is retained. I personally think that it a great research work. I strongly recommend Dr. Rana and his group members to use this methodology in the water purification systems and try to commercialize their material.
Interesting work done by the authors is an important addition to technological options to clean contaminated water. Reported regeneration and filtering efficiency self explains its potential. Congratulations to Dr. Rana and the team for excellent work.
Dr. Johnson, Dr. Dipak Rana and his group have a great contribution in developing a quality membrane for the treatment of polluted water. Their discovery of Nanofibrous MOF membrane has opened an excellent approach to deal with heavy metal water pollution. The multiple interactions e.g. ion exchange, electrostatic interactions, pore filling and surface adsorption nature of the membrane has provided an ultra-high adsorption property. The important part of their research is the re-usability of the membrane with adequate capacity for drinkable water treatment which makes it more attractive for commercialization point of view. Authors are still expecting to get improvement over their current innovative discovery. A big congratulation to an amazing talented group. Wish you all the best for future.
Excellent work done by the Dr. Rana and his team for the removal of heavy metal from the drinking water. Safe drinking water is one of the basic necessities for the society. Current commercial method to remove heavy metals tends to be costly, and not efficient enough. The application of nanofibrous MOF membrane has shown a new avenue for removal of toxic heavy metal and make the water drinkable. The technology is in the process of commercialisation and definitely a boon for the society. Congratulations to Dr. Rana and his team and wish you best for future research.
Congratulations to Dr Rana and his colleagues for their innovative work and novel technique for the purification of drinking water. This is an excellent technique for removal of toxic heavy metals. The membrane filtration technology with the recycling process is based on combinations of several conventional techniques which provide durability and cost effectiveness. Millions of people around the globe will benefit from this work. Keep it up and best wishes for upbringing the technology to the commercial stage.
Metal-organic frameworks (MOFs) have been proved as promising adsorbents because of excellent porosity, designable adsorption sites, and controllable water stability. Dr Rana and his group details the breakthrough discovery of nanofibers MOF membranes for removing heavy metals ions. The adsorption behaviors of the materials and corresponding structure-performance relationships were discussed exclusively for efficient water purification. My sincere congratulations to Dr. Rana and his esteemed research group for award winning applied research. I think it will be very useful if Dr. Rana get more funds to explore more on this excellent research topic. I wish him all the best for his future endeavor.
Excellent article by Rana et al on water purification that enlightens the researchers aiming to provide potable water in the most water-insecure regions.
This is an excellent and interesting piece of work published by Dr Rana and his research team. Sustainable production of potable water has always been a challenging task in various aspect. Membrane technology has emerged as one of the promising technology for the production of portable water. In this context, removal of heavy metal contamination from ground and or industrial water is one of specific challenge to scientific community worldwide. Many researchers have employed wide range of material for fabrication of suitable membrane to offer a solution for the removal of heavy metals from water. Development of MOF based membrane by Dr Rana’s research team is commendable for the removal of heavy metals from water. Their studies also have shown the potential for commercial application.
Another breakthrough in the field of MOF for the purification of heavy metal ions such as Pb2+ and Hg2+ contaminated water was published by Rana and co-workers. The developed MOF-supported nano-fibres effectively filter the toxic Pb2+ and Hg2+ions. The present research might help people to access clean drinking water at some point in future if the research is effectively applied in real-life applications. I wish you good luck to all the group members and keep working on research that improves the quality of life and I hope their research will be applied soon in real-world use.
Great achievement by Professor Rana and his group members. Heartfelt congratulations to the team. We are eagerly waiting to see that this work will be marketed soon for the benefit of society.
Excellent work.
Great work by Prof. Rana and his research group. This work will provide a new light in the research area related to purification of water. Best wishes to Prof. Rana and all his group members for the upcoming publication.
An outstanding article by Rana et al. on water purification enlightens the researchers seeking to deliver potable water in the most water-insecure provinces.
Excellent work. Congratulations to Prof. Rana and his research group. Hopefully Rana et al. will published more interesting papers related to water purification in near future.
The heavy metal ions from industrial sources can damage the foundations of life and aquatic life, primarily through the food system. In this context, MOF-nanofibrous membranes have been a promising success in the era of upcoming global disasters. Scientific communities appreciate Dipak Rana’s group work at the Industrial Membrane Research Institute, Department of Chemical and Biological Engineering, University of Ottawa, Canada.
The fascinating and valuable work regarding the systematic study of the heavy metal interaction with the MOF alone, with the nanofiber membrane, and with the MOF supported on nanofibrous materials. The membrane filtration module could remove Pb(II) ions from the solution with moderate permeance of 248.57 L m-2 h-1 bar-1 for a membrane thickness of 560 μm where the purity of the permeate met the drinking water standards! It is an outstanding achievement for water purification!!
In a world where environmental issues regularly make headlines, water contamination is of great concern, especially in communities with nearby mining operations. University of Ottawa senior researcher Dr. Dipak Rana and his team have developed a filter made of metal-organic frameworks (MOFs) that can remove heavy metal ions like cadmium (+2), lead (+2), mercury (+2), zinc (+2), etc., from contaminated wastewater.
The filter works at the molecular level as contaminated water passes through the MOFs embedded electro-spun nanofibers filter, causing the exchange of ions due to electrostatic interactions. This exchange fills up the pores of the high adsorption capacity filter with the ions of the unwanted heavy metals. Afterward, the filters can be cleaned with acid solutions and reused, while the metals can be reclaimed and repurposed for various industrial applications.
It is an excellent work indeed. Your discovery will show the path for the many countries where heavy metal is a major problem for their potable water. Many industrial discharge which contained a lot of heavy metals will solve the problem for them.
Thanks a lot Prof Dr. Rana for your work and discover something for mankind
Water quality is one of the major concerns in the present world. When the quality of water is reduced significantly due to heavy metal contamination, it becomes a threat to humankind. This project serves the purpose of maintaining high-quality standards of water and could be applied to different sectors across the world. Thank you Dr. Rana for your significant contributions.
An excellent work by Rana et al. of University of Ottawa, on removal of highly toxic heavy metals Pb2+ and Hg2+ by using metal organic framework (MOF). This work is very interesting and useful for the treatment of wastewater coming from various industries. Best wishes to Prof. Rana and all his research members for their findings.
The research team has done an excellent job of purifying water, with their findings. The work by Rana and his colleagues will help in providing a new light in the area of water purification and removal of highly toxic heavy metals such as Pb2+ and Hg2+.
This is an excellent work in the field of work done in connection with the process of purifying water via metal organic framework(MOF). It highlights the new field of works towards the purifying water for better benefits of human being. Thanks to Dr Dipak Rana and his team.
It is believed that finding innovative ways to treat water to make it more drinkable can benefit individuals everywhere. People often consider what substances may be present in our water, even in developed countries where we typically have good and safe drinking water. However, we still use a Brita filter in case heavy metals from pipes or river water are present. After all, we don’t want heavy metals in our bodies. If we can conduct testing using smaller portable kits, and mobile vehicles, or even establish small plantations in some smaller communities to test these nano-fibrous membranes, including metal-organic frameworks (MOFs), for their effectiveness, it would be advisable and excellent. Potential research and development in safe drinking water, as well as prospective aid to other developing and underdeveloped countries, are some of the ways we can see positives in continuing forward with this technology developed at the Industrial Membrane Research Institute, Department of Chemical and Biological Engineering, University of Ottawa, Canada. It is noted that heavy metals, with a density greater than 5 g/cm3, which are more common in our everyday lives such as Arsenic, Cadmium, Chromium, Cobalt, Copper, Gold, Iron, Lead, Manganese, Mercury, Molybdenum, Nickel, Platinum, Silver, Titanium, Tin, Vanadium, Zinc, etc., create pollution in the environment and have toxicological effects on humans. It has been observed that heavy metal ions interact with the cell membrane, deoxyribonucleic acid (DNA), enzymes, lysosomes, mitochondria, nuclei, and nuclear proteins, thus causing DNA damage, consequently leading to carcinogenesis, cell damage, loss of cellular function, and neurotoxicity. Therefore, I strongly believe that the innovative MOFs-embedded nano-fibrous membranes research, originated by Dr. Dipak Rana and his group members, will provide a novel methodology for mitigating the contamination problem of heavy metal ions in drinking water.
Nanofibrous Metal-Organic Framework (MOF) membranes are a promising technology for water purification due to their high surface area, tunable porosity, and chemical selectivity. MOFs are crystalline materials composed of metal ions or clusters connected by organic ligands, forming porous structures with unique properties. When fabricated into nanofibrous membranes, MOFs offer enhanced performance in water purification applications compared to traditional membranes.
Here’s how nanofibrous MOF membranes work for water purification:
1. **High Surface Area**: Nanofibrous membranes have an extremely high surface area-to-volume ratio due to their nanoscale fibers. This high surface area allows for more efficient adsorption of contaminants from water.
2. **Tunable Pore Size**: MOFs have tunable pore sizes, which can be adjusted by selecting appropriate metal ions and organic ligands during synthesis. This tunability enables selective removal of specific contaminants based on their molecular size and properties.
3. **Chemical Selectivity**: MOFs can be designed to exhibit high chemical selectivity towards certain contaminants. By choosing the appropriate MOF composition, researchers can tailor the membrane to target specific pollutants while allowing water molecules to pass through.
4. **Adsorption Capacity**: MOFs have high adsorption capacities for various contaminants, including heavy metals, organic pollutants, and even some pathogens. This property allows nanofibrous MOF membranes to effectively remove a wide range of impurities from water.
5. **Regenerability**: Unlike some other water purification methods, nanofibrous MOF membranes can be regenerated after use. By applying appropriate regeneration techniques, such as heating or solvent washing, adsorbed contaminants can be desorbed from the MOF surface, allowing the membrane to be reused multiple times.
6. **Scalability and Efficiency**: Nanofibrous MOF membranes can be manufactured using scalable techniques such as electrospinning or layer-by-layer assembly. This scalability, combined with their high efficiency in contaminant removal, makes them suitable for large-scale water purification applications.
7. **Potential Challenges**: Despite their many advantages, nanofibrous MOF membranes also face challenges such as stability under varying environmental conditions, long-term durability, and cost-effectiveness of production. Research is ongoing to address these challenges and further improve the performance of MOF-based water purification technologies.
Overall, nanofibrous MOF membranes hold great promise for addressing water purification challenges by providing efficient, selective, and scalable solutions for removing contaminants from water sources. Continued research and development in this field are likely to lead to even more advanced and practical water treatment technologies in the future.