Soumyadeep Mukhopadhyay | University of Malaya, Malaysia (original) (raw)

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Papers by Soumyadeep Mukhopadhyay

Applications of colloidal gas aphrons for pollution remediation

An environment-friendly arsenic removal technique from contaminated soil with high iron content h... more An environment-friendly arsenic removal technique from contaminated soil with high iron content has been studied. A natural surfactant extracted from soapnut fruit, phosphate solution and their mixture were used separately as extractants. The mixture was most effective in desorbing arsenic, attaining above 70% efficiency in the pH range of 4-5. Desorption kinetics followed Elovich model. Micellar solubilization by soapnut as well as arsenic exchange mechanism by phosphate are the probable mechanisms behind arsenic desorption. Sequential extraction reveals that the mixed soapnut -phosphate system is effective in desorbing arsenic associated with amphoteric-Fe-oxide forms. No chemical change to the wash solutions was observed by Fourier Transform-Infra Red spectra. Soil: solution ratio, surfactant and phosphate concentrations were found to a ffect the arsenic desorption process. Addition of phosphate boosted the performance of soapnut solution considerably. Response Surface Methodolog...

Bulletin of environmental contamination and toxicology, Jan 13, 2016

Phosphate and colloidal gas aphrons (CGAs) generated from saponin extracted from Sapindus mukoros... more Phosphate and colloidal gas aphrons (CGAs) generated from saponin extracted from Sapindus mukorossi fruit, were evaluated for washing low levels of arsenic from an iron rich soil. Phosphate is one of the most commonly dispersed chemicals that increases arsenic mobility in soil due to their structural similarities, making it an important factor in arsenic removal process. Column washing experiments were performed with CGAs in down flow and up flow modes on soil of pH 5 and 6. Soapnut CGAs, when paired with phosphate removed up to 95 % arsenic while soapnut CGAs alone could only remove up to 70 % arsenic. The presence of phosphate improved efficiency of soapnut solution by up to 35 %. SEM image of washed soil revealed minor corrosion of soil surface while using phosphate with soapnut. Therefore, the addition of phosphates would have positive impact on soil washing using soapnut saponin.

Indian journal of experimental biology, 1992

Journal of the Taiwan Institute of Chemical Engineers, 2013

Journal of Environmental Sciences, 2014

Critical Reviews in Environmental Science and Technology, 2014

Journal of Environmental Sciences, 2013

International Journal of Environmental Science and Technology, 2013

Environmental Pollution, 2009

Malaysia is gifted with abundant groundwater resources. However, most of it has iron content as h... more Malaysia is gifted with abundant groundwater resources. However, most of it has iron content as high as 10 mg/L compelling the water supply companies to treat it using separate treatment facilities before delivering it to the consumers. Problems of filter clogging and construction of facilities to manage considerable amount of iron sludge are the operational and financial constraints. The proposed technology for in-situ treatment of groundwater attempts to eliminate the problem at its origin. This involves pumping up the ...

Water and Environment Journal, 2019

Malaysia contains elevated levels of iron in shallow groundwater in the range of 3-7 mg Fe/L comp... more Malaysia contains elevated levels of iron in shallow groundwater in the range of 3-7 mg Fe/L compared to USEPA safe limit of 0.3 mg Fe/L. Air Kelantan Sdn Bhd in Malaysia uses “River Bank Filtration” (RBF) technology to harvest hyporheic water. RBF treatment removes turbidity of the river water through river bed acting as a filter, but is unable to remove the Fe from the harvested water. This work proposes a technology to reduce Fe concentration in the extracted water using granular activated carbon in a laboratory scale rotating packed bed contactor (RPBC). Taguchi method was used for optimizing operating conditions for adsorption of Fe onto activated carbon in RPBC system. Taguchi optimisation results showed that a removal efficiency of 87% Fe from a 50 mg Fe/L concentration could be achieved by RPBC at initial pH of 6.5, feed rate of 40 L/h, rotating speed of 1600 rpm and packing density of 357 kg/m3.

ABSTRACT Heavy metal contamination of soil and water is harmful because of their persistent behav... more ABSTRACT Heavy metal contamination of soil and water is harmful because of their persistent behaviour. The soil of Klang valley used in this study is alluvium by nature having very high iron content resulting from granitic erosion processes. The very high iron content of the soil demands research on suitable technology that can sustainably clean-up the heavy metals with minimum environmental degradation. Usually chemical soil washing leads to structural change in soil and excessive degradation. So the performance of a natural surfactant derived from soapnut, Sapindus mukurossi, is being evaluated and compared with traditional anionic surfactant SDS. Soapnut was found to achieve nearly up to 69% extraction capacity as that of SDS and thus soapnut deserves further research in this field.

2 Colloidal gas aphrons (CGAs), first described by Felix Sebba in his book "Foams and Biliqu... more 2 Colloidal gas aphrons (CGAs), first described by Felix Sebba in his book "Foams and Biliquid Foams 3 Aphrons" in 1987, consist of a system of spherical microbubbles with diameter mostly above 25 μm and 4 classified as kugelschaums (ball foam). They possess some colloidal properties and can be pumped at 5 uniform rate through pipes and channels, much like liquids. Also, they have high stability due to very 6 small size and thick surfactant shells. Research works published over the period of the past two decades 7 indicate effective applications of CGAs for clarification of particles and microorganisms, protein 8 separation, gas and nutrient transfer and pollutant separation from water and soil matrices. In this review 9 paper, the generation techniques of CGAs and their application for pollution abatement have been 10 discussed. Some mineral separation processes by CGAs flotation have also been reviewed because of 11 their relevance to the contaminant removal processes. T...

Several large Irish lake fisheries comprise both pike (Esox Lucius) and brown trout (Salmo trutta... more Several large Irish lake fisheries comprise both pike (Esox Lucius) and brown trout (Salmo trutta). Due to predation on trout, pike stocks are actively managed in several locations with the objective of enhancing the trout fishery, which is a policy strongly supported by some trout anglers but intensely opposed by pike anglers. In the context of scientific support for management decisions concerning these mixed resource fisheries there is a dearth of economics knowledge. This paper addresses some of that knowledge gap, investigating factors affecting angling recreational demand within these mixed resource fisheries and whether there are significant differences between pike and brown trout anglers. We estimate a travel cost model and test whether pike and trout anglers have different demand preferences. The most substantive policy-relevant finding from the research relates not to differences associated with target species but to angling club membership. Angling club members are more ...

Journal of Water Process Engineering