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Water information

Research

Dec 8th, 2019
Hydrogen as water information carrier
  • Water Interactions
  • Water Interactions

Electrically induced forces are playing a key role in biological systems, matching known theories of field-charge and field-dipole interactions. However, the specific interactions of induced and very low electromagnetic fields naturally present at the environment on living systems are not yet fully understood. The theory that in living systems have a certain coherent longitudinal electric modes are strongly excited, and stabilized by deformations arising from nonlinear effects was first subjected in the late sixties (Fröhlich, 1968). The sense of smell in that context is a great example of a biological sensor that can detect and diagnose an enormous number of airborne compounds. Odor vibrational theories trying to explain the elusive effects that cannot be explained by molecular structure alone.

Support to the existent of vibrational mode in living organisms at room temperature was recently published, using a large literature review Geesink (2016) shows that considering the effects of electromagnetic radiation on in vitro and in vivo life systems.  Hydrogen as the basic element has a key role for both biological and water structure, its ability to mediated from water to matter is important link between living matter, water, and waves was not yet specified. The main objective is to quantify the induced electromagnetic field and the vibrational modes in water and hydrogen, in particular, its function in transferring odor information and the effect on olfactory as a biological sensor.

Ozonation of lignocellulosic waste for ethanol production

Research

Apr 11th, 2018
Ozonation of lignocellulosic waste for ethanol production
  • AOPs
  • AOPs

Lignocellulosic waste (in this study municipal trimming) is a promising sustainable feedstock for ethanol production, but require costly and polluting pretreatment, that often result in toxic byproducts. Ozonation is a nonpolluting, effective pretreatment method, but is not used commercially due to the high energy requirements of the assumingly high ozone doses needed. Results demonstrated that both ozonation time and enzyme dose (at optimal pH) impact conversion efficiency to glucose. Ozonation (15 and 90 min, accumulated TOD=318 and 1114 mgO3/L) of water-submerged waste (at pH=5.5) prior to enzyme addition at (×1.5 industrial enzyme dose) enabled high conversion of the cellulose fraction of the waste to glucose (31% and 42% respectively) compared to non-ozonated sample (with enzyme, 12%), suggesting ozonation could offer an effective and feasible pretreatment method. In these ozone doses, only 20% and 40% of the lignin was degraded showing that there is no need for delignification (as opposed to the common hypothesis) to obtain high sugar conversion. In addition, ozone process can be easily monitored by change in absorbance at 230, 280 and 436 nm, making it useful to use spectral scan in the field. Moreover, reduction in net calculated energy balance was obtained at higher ozone dose (90 min compared to 15 or 30 min), demonstrating increased process efficiency at lower ozone doses. Consequently, ozonation can be generated on-site and on demand, enabling decentralized pretreatment operated near the feed source thus overcoming transportation costs.

Disinfection by light emitting diodes (LED)

Research

Mar 14th, 2018
Disinfection by light emitting diodes (LED)
  • Microbiology
  • Microbiology

UV irradiation is a well-established practice for water disinfection of pathogens. To-date two types of mercury vapor-filled lamps produce germicidal UV irradiation which are either monochromatic (low-pressure, LP) and polychromatic (medium-pressure, MP). LP lamps emit light at 254nm, while MP lamps emit light at multiple peaks between 200 nm and above, one of them being at 254nm. MP lamps emit wavelengths that may be more effective in inactivating water pathogens and preventing repair but these lamps are expensive, require high drive voltage, have lower germicidal efficiency and produce a lot of heat resulting in high fouling and consequently need for frequent and expensive chemical and mechanical maintenance. LP lamps may be less effective for inactivation of certain microorganisms; however they produce considerably less heat resulting in less fouling and possess higher germicidal efficiency (based on UVC wavelengths). The light emitting diodes (LED) are considered a new UV source that can replace conventional mercury gas-filled lamps in water disinfection. UV LEDs emit light at different UV ranges (UVA/B/C). UV-LEDs are monochromatic (i.e. emit at a very narrow wavelength band), are selectable thus emission spectrum can be tailored, require no warm up period, are flexible and have lower electricity consumption. Disinfection reactors using UVC LEDs, are already used in small scale point-of-use water treatment devices, and implemented in our laboratory. 

Production of Crystalline Nanocellulose (CNC)

Research

Mar 11th, 2018
Production of Crystalline Nanocellulose (CNC) and its application for water
  • AOPs
  • AOPs

Crystalline nanocellulose (CNC) is a natural, renewable polymer which is composed of rod-like nanocrystals of cellulose with average dimensions of 100 nm in length and 5 nm in diameter. CNC possesses unique optical and mechanical properties, such as high aspect ratio, low density, high tensile strength, etc. Such properties make CNC a highly useful material for the manufacturing of various bioproducts. In recent years, interest in CNC intensifies as the industry realizes its potential, especially with its production being cheap and based on extraction from plants.

There are, however, several problems that arise by the production of crystalline nanocellulose from plants, such as a waste of water and the occupation of agricultural lands. An even more environmental production of CNC might be achieved by using recycled paper sludge (RPS) instead of plants, as RPS consists mainly of wood – which is very rich in cellulose as well.

The goal of this study is to try and develop an environmental-friendly method of producing CNC from RPS, while examining two approaches:

  1. Chemical Hydrolysis: a hydrolysis using malic acid (di-carboxylic acid). Using such acid rather than the conventional use of phosphoric or sulfuric acid may add carboxylic groups to the cellulose, allowing higher electric charges and a better separation and recycling because it is a weak acid.
  2. Enzymatic Hydrolysis: incubation with enzymes may prove highly effective for crystal utilization.

The next step of the research will be manufacturing membranes that are made of CNC, which will be produced from the RPS, for various water treatments such as an adsorption of dyes from textile industry or heavy metal ions from wastewater.  

Municipal leachate treatment by AOP

Research

Mar 5th, 2018
Municipal leachate treatment by AOP

In collaboration with Prof. Mohan S., Dept. of Civil Engineering,  IIT Madras, India

  • AOPs
  • AOPs

In most of the developing nations like India, almost 85 percent of generated waste goes to open dumping (WHO) due to improper segregation of wastes. Even in many developed countries ultimate disposal option is use of landfill. The urbanization has a major impact on municipal solid waste generation rate and the rate has been reported phenomenal increasing rate in general. The increasing municipal solid waste generation further adds to the problems associated with open dumps. One of the major problems of concern is the ground water contamination by leachate from the open dumps. The interaction of waste with water especially during rainy periods or summer that percolates through the open dumps produces highly polluted wastewater termed as leachate. There are many factors like affecting the quality and the quantity of such leachate, i.e., seasonal weather variation, landfilling technique, piling and compaction method, waste type and composition, structure of the landfill, etc.

 Leachate contains large amount of organic matter of which Humic substances are the major group along with ammonia nitrogen, toxic metals, chlorinated organic, phenolic compounds, pesticide residues and endocrine disruptors like phthalates which are considered as priority pollutant by US EPA. Biological process has very less efficiency in removing the phthalates due to its toxic characteristics. Physicochemical processes have been successfully applied for the removal of recalcitrant substances from stabilized leachate and refining the biologically pre-treated leachate. Among various physicochemical processes, Advanced Oxidation Processes (AOPs) have been widely applied to complete removal of phthalates in leachate that are non-biodegradable and/or toxic to microorganisms.

At present, we are working on treatment of phthalates by considering Diethyl phthalate (DEP) as a model compound due to its high solubility and toxic in nature by Ozonation (O3) and Ozone in combination with Hydrogen peroxide (O3/ H2O2) for complete degradation of phthalates and its transformation products. Our main focus will be of complete treatment process which degrades DEP and other organic contaminants from the leachate. 

Visible light driven, self-cleaning photocatalysts for water treatment and purification

Research

Mar 4th, 2018
Visible light driven, self-cleaning photocatalysts for water treatment and
  • Nano Materials
  • Nano Materials

Photocatalysis is a process which uses electromagnetic radiations (EMR) in order to activate catalysis and initiate the chemical reaction. Among all the various advanced oxidation processes it has found wider use from environment to energy application.

So how a photocatalyst Works?

Photocatalyst which is normally a semiconductors (metal oxides such as ZnO, TiO2) with a particular electronic structure and when you irradiate with photons, energy greater than the band gap energy (Eg) of semiconductor excite electron (e) from valence band (VB) to conduction band (CB) leaving this hole (h+) highly oxidised. So, if you have organic molecules (micropollutants) that are in contact with the hole it readily oxidise to CO2 and minerals. The most important thing is to make sure the e- and h+ are captured by the targeted molecules (pollutants) immediately, if not then they recombine and there will be no reaction and this is critical to design a good photocatalyst. Majority of work done till now are concentrated on material design. More than 85% of papers on photocatalysis that published are on making materials. We are less aware of surface reaction and process system. So, my contribution to the field is exploring and combining all together.

We are focused on designing visible light driven photocatalyst with high photon efficiency by reducing the recombination of electron–hole pairs with innovative chemistry design; we project our photocatalyst to treat water with natural sunlight instead of UV light and dramatically reduce costs for operators and to make antifouling self-cleaning materials for buildings and coating industries.

We’re also concerned to treat highly contaminated electroplating wastewater (WW) or any source with high loads of metals by using the indigenous metals in the WW as elements that enhance the process efficiency. This is a new and innovative concept in treatment of WW where the metal contaminants participate and accelerate the process for advancing their subsequent removal as well as other contaminants. A novel hybrid process is designed for accelerating visible light catalytic processes by the oxidized/reduced indigenous metals for targeting their removal and other contaminates and utilizes the metals in the sludge as accelerators in enhancing biofuels and biofertilizers yield from metallurgical industry waste water expeditiously. 

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