Browsing by Author "D.B. Pal"

Now showing 1 - 5 of 5

Arsenic removal from synthetic waste water by CuO nano-flakes synthesized by aqueous precipitation method
(Desalination Publications, 2017) D.B. Pal; D.D. Giri; P. Singh; S. Pal; P.K. Mishra
Arsenic contamination in the drinking water is a serious issue affecting health of inhabitants of developing countries like India and Bangladesh and needs cost effective solutions. The nanomaterials having large surface area per unit volume could be useful adsorbent for water arsenic decontamination. The CuO nanomaterial synthesized by aqueous precipitation method. The obtained nanomaterial suspension sonicated for 15 min before centrifugation at 5,000 g for 10 min. Thoroughly washed and overnight dried pellets at 60°C characterized by scanning electron microscope revealed nanoflakes structure of the pellets. The copper nanoflakes (CONF) have monoclinic CuO structure in XRD analysis. The kinetics of arsenic adsorption determined by varying arsenic content and dose of adsorbent for a period of 1 h revealed second order adsorption kinetics. The synthesized nano-flakes have potential application for arsenic removal from water well below safe limit. © 2017 Desalination Publications. All rights reserved.
Assessment of ground and surface water quality along the river Varuna, Varanasi, India
(Kluwer Academic Publishers, 2015) Pardeep Singh; R.K. Chaturvedi; Ankit Mishra; Lata Kumari; Rishikesh Singh; D.B. Pal; Deen Dayal Giri; Nand Lal Singh; Dhanesh Tiwary; Pradeep Kumar Mishra
Multivariate statistical techniques were employed for monitoring of ground-surface water interactions in rivers. The river Varuna is situated in the Indo-Gangetic plain and is a small tributary of river Ganga. The study area was monitored at seven sampling sites for 3 years (2010–12), and eight physio-chemical parameters were taken into account for this study. The data obtained were analysed by multivariate statistical techniques so as to reveal the underlying implicit information regarding proposed interactions for the relevant area. The principal component analysis (PCA) and cluster analysis (CA), and the results of correlations were also studied for all parameters monitored at every site. Methods used in this study are essentially multivariate statistical in nature and facilitate the interpretation of data so as to extract meaningful information from the datasets. The PCA technique was able to compress the data from eight to three parameters and captured about 78.5 % of the total variance by performing varimax rotation over the principal components. The varifactors, as yielded from PCA, were treated by CA which grouped them convincingly into three groups having similar characteristics and source of contamination. Moreover, the loading of variables on significant PCs showed correlations between various ground water and surface water (GW-SW) parameters. The correlation coefficients calculated for various physiochemical parameters for ground and surface water established the correlations between them. Thus, this study presents the utility of multivariate statistical techniques for evaluation of the proposed interactions and effective future monitoring of potential sites. © 2015, Springer International Publishing Switzerland.
Current and emerging trends in bioremediation of petrochemical waste: A review
(Taylor and Francis Inc., 2017) Pardeep Singh; Rajat Jain; Neha Srivastava; Anwesha Borthakur; D.B. Pal; Rishikesh Singh; Sughosh Madhav; Pratap Srivastava; Dhanesh Tiwary; Pradeep Kumar Mishra
Various industries release harmful petrochemical contaminants into the environment. To treat these petrochemical contaminants at source, different physical, chemical, and biological methods have been proposed and applied worldwide. However, physical and chemical methods have their own advantages and limitations; in this review, we majorly focused on the biodegradation of petrochemical wastes. First, a background study on the literature available in this field is presented. Second is a review of the toxic effects of petrochemical waste and various physical and chemical processes, followed by elaborate biological processes available for petrochemical waste degradation. Further, different aspects of bioremediation, such as modes, factors, limitations, and future perspectives are critically reviewed and presented. It was found that most of the studies performed on bioremediation of petrochemical waste employed bacteria for the degradation purpose. Some studies also made use of algae, fungi, yeast, genetically modified organisms, biosurfactants, or a consortium of these microbes. Moreover, use of bioremediation is still limited at field scale due to certain limitations, which have been elaborated in this article. Overall, we strongly believe that with bioremediation capturing the attention of environmentalists worldwide, there is still a prevailing need to scale up from lab to land level applications and adaptations. © 2017 Taylor & Francis Group, LLC.
Methylotrophic bacteria in relation to soil and plant health
(Nova Science Publishers, Inc., 2015) Deen Dayal Giri; Ajay Kumar; Lata Kumari; Pardeep Singh; D.B. Pal; K.D. Pandey; P.K. Mishra
Methylotrophs are a diverse group of microorganisms that can use reduced onecarbon compounds, such as methanol or methane, as the carbon source for their growth; and multi-carbon compounds that contain no carbon bonds, such as dimethyl ether and dimethylamine. Utilization of various types of organic compounds present in the coal mine spoil as carbon substrate is the the reason for better survival of facultative methylotrophic bacteria in stressful and nutrient poor coal mine spoils. Methylotrophic bacteria significantly modify the physicochemical properties of degraded soil. The nutrients released from death and decay of methylotrophic bacteria facilitate growth of heterotrophic bacteria and increases microbial diversity of the degraded land. This chapter gives brief description of methylotrophic bacteria and their role in improvement of soil and plant health have given special attension. © 2015 by Nova Science Publishers, Inc. All rights reserved.
Photocatalytic degradation of Acid Red dye stuff in the presence of activated carbon-TiO2 composite and its kinetic enumeration
(Elsevier Ltd, 2016) Pardeep Singh; M.C. Vishnu; Karan Kumar Sharma; Anwesha Borthakur; Pratap Srivastava; D.B. Pal; Dhanesh Tiwary; Pradeep Kumar Mishra
The present paper deals with photocatalytic degradation of effluents from dye industries which have known toxic impacts on flora and fauna. Nano composite of titanium dioxide having activated carbon (TiO2/AC) base was synthesized using sol-gel method. The synthesized catalyst was then characterized by Fourier Transform-Infrared (FT-IR) spectroscopy, Scanning Electron Microscopy (SEM), X-ray Diffractometry (XRD) and Brunauer Emmet Teller (BET) surface area analyzer. A synthetic solution of AR-131 dye was subjected to photocatalytic degradation using TiO2/AC nano composite as catalyst. The degradation mechanisms of dye (AR-131) via photo-catalysis were found to follow a first order kinetics mechanism (vis. Langmuir- Hinshelwood Model). Toxicity of spent catalysts was further investigated in seed germination of Vigna radiata. Enhanced seed germination along with elongation of root and shoot was noticed up to the concentration of 500 ppm confirming its non toxicity. © 2016 Elsevier Ltd.