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A Novel Approach to Utilize Used Disposable Paper Cups for the Development of Adsorbent and its Application for the Malachite Green and Rhodamine-B Dyes Removal from Aqueous Solutions
2020
Kshipra Shukla, Alka Verma, Lata Verma, Shalu Rawat and Jiwan Singh
This study focuses on the removal of organic dyes, such as Malachite Green (MG) and Rhodamine-B (Rh-B) from an aqueous solution with the help of a novel adsorbent (activated carbon) with magnetic property prepared by used disposal paper cups (AC@PC) at 500°C. The synthesized AC@PC adsorbent was characterized by using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), Energy dispersive X-ray spectroscopy (EDS) and point of zero charge (pHZPC). Adsorption of MG and Rh-B onto the AC@PC adsorbent from aqueous solution was investigated systematically. Langmuir, Freundlich and Temkin isotherms were also studied, however, it has been observed that Langmuir isotherm model was best fitted for both the dyes, which describe the adsorption behaviour at equilibrium. Pseudo-first and pseudo-second order kinetic model describe the rate of adsorption. Kinetic study explained that the process of adsorption followed the pseudo-second order model. Thermodynamic parameters such as enthalpy (?H°), entropy (?S°) and Gibb’s free energy (?G°) were also studied and revealed that the adsorption of MG was endothermic, whereas adsorption of Rh-B was exothermic onto the AC@PC. The prepared adsorbent shows potentially high adsorption properties for both the dyes.
Показать больше [+] Меньше [-]Influence of Tannery Effluents on Morphological Characters of Ipomoea pes-caprae (L.) Sweet and Clerodendron inerme (L.) Gaertn.
2020
A. Venkatesan
Tannery industry is common in many parts of the world, which is polluting groundwater ecosystems and producing major heavy metals and sodium chloride. The present study is aimed at some morphological characters in phytoremediation of heavy metals and ions from tannery effluents by using halophytic species such as Ipomoea pes-caprae and Clerodendron inerme. The morphological characters were analysed at an interval of 30, 60, 90 and 120 days. The results indicated that all the morphological characters were increased with an increasing concentration of tannery effluents and no injury symptoms in growth condition. It may be concluded that these halophytic species are potentially suitable for phytoremediation of heavy metals from the tannery effluent contaminated soils, which will reclaim the soil for further use as crop cultivation or crop improvement.
Показать больше [+] Меньше [-]Capital Allocation Efficiency Evaluation of Energy Conservation and Environmental Protection Enterprises in the Yangtze River Delta of China
2020
Hongjun Xiong
Various measures are implemented to promote the construction of China’s ecology. These measures aim to accelerate the green transformation of the economy and promote the rapid development of energy conservation and environmental protection industry under the promotion of relevant policies. Consequently, the numbers of enterprises and the market scale have shown explosive growth. However, energy conservation and environmental protection enterprises are faced with lack of technological innovation, shortage of capital, and high cost. Effective measures must optimize the efficiency of capital allocation. To evaluate the capital allocation efficiency of energy conservation and environmental protection enterprises, 26 listed companies of energy conservation and environmental protection in the Yangtze River Delta of China were selected as samples. Monetary capital, accounts receivable, inventory, fixed assets, and construction in progress were used as input scalars. Net profit, undistributed profit, and surplus reserve were used as output variables. The Data Envelopment Analysis (DEA) model was used for analysis. Results show that capital allocation efficiency of 11 sample companies is DEA-effective. Power, heat, gas, water production, and supply industry rank first with the real estate industry divided by industry. Shanghai ranks first in the regional division. Specific improvement strategies are proposed for non-DEA effective sample enterprises.
Показать больше [+] Меньше [-]Analysis and Quantification of Airborne Heavy Metals and RSPMs in Dehradun City
2020
Abhinav Srivastava, Arnab Mondal, N.A. Siddiqui and S.M. Tauseef
Air pollution is becoming a major environmental and public health problem worldwide. Exposure to different air pollutants has several adverse effects on human health. In the present study, we attempt to determine the concentration of respirable suspended particulate matters (RSPMs) and levels of the heavy metals in ambient air of Dehradun city. The RSPM concentration of all the areas under study were well under the NAAQ standard limit. The Ghantaghar area reported the maximum RSPMs of 87.5507 ?g.m-3. The samples collected from four different locations of Dehradun were primarily analysed for heavy metals like Pb, Fe, Cr and Cd using atomic absorption spectrophotometer. The measured concentrations were compared with the standard safe limits provided by United States Environmental Protection Agency (USEPA). It is seen that all the heavy metals, as well as the RSPM, are well under permissible safe limits set by USEPA, OSHA, and CPCB. It can, therefore, be concluded that the ambient air quality of Dehradun, in terms of heavy metal contamination as well as RSPM concentration in air is safe. Strict monitoring of heavy metal emissions in air should be done regularly to maintain the ambient air of Dehradun area as healthy.
Показать больше [+] Меньше [-]Prototype of Eco-Friendly Indoor Air Purifier to Reduce Concentrations of CO2, SO2, and NO2
2020
Saisantosh Vamshi Harsha Madiraju, P.V.S. Gopi Raghunadh , K. Ravi Kumar
Urbanization and industrialization lead to the increased usage of fossil fuels for running various types of automobiles and industries in developing countries. The rapid growth of automobiles usage in major cities causes air pollution and its direct impact on public health. This impact is alarming the worsening of the health of urban dwellers. But this impact can be reduced by breathing the filtered air. Filtering of air can be done in multiple ways. Among all, filters prepared from natural materials have become popular. In this study, an attempt has been made to find the novel approach to reduce the pollutants’ level in the air by preparing prototype indoor air purifier which is designed, fabricated and tested with eco-friendly materials and adsorbents prepared from plant extractions. The three pollutants considered were CO2, SO2, and NO2. Activated carbon was used as an adsorbent for CO2 and NO2 removal, whereas Neem bark, Mango bark, Orange peel powder and Neem leaf powder were used for SO2 removal. The prototype was designed for Hyderabad city, Telangana State of India and tested at houses of five different locations (Balanagar, Jeedimetla, Zoo Park, MGBS and JNTU) which are major traffic intersections in the city. The level of pollution before and after the installation of the instrument was measured for three months (January, February, March) and analysed. Results indicate the improvement of air quality after filtration.
Показать больше [+] Меньше [-]Extraction and Spectrophotometric Estimation of Fe3+, Cd2+, Pb2+ and Zn2+ From Industrial Effluents Using Synthetic Supramolecular Ligand
2020
Sachin Patil, Milind Kondalkar, Umesh Fegade, Sanjay Attarde and Sopan Ingle
Increased water pollution due to toxic heavy metals is becoming a serious threat that has been faced by the entire world in the last few decades. To overcome this problem a suitable complex ligand was designed for removal of Fe3+, Cd2+, Pb2+ and Zn2+ from the effluents. The work incorporated the synthesis of (4Z)-4-((2Z)-2-(2,5-dihydro-2,3-dimethyl-5-oxo-1-phenyl-1H-pyrazol-4-ylimino) ethylidene amino)-1,2- dihydro-1,5-dimethyl-2-phenylpyrazol-3-one (Supramolecular Ligand) by the condensation method and confirmed by FTIR and 1HNMR spectroscopic methods. The batch extraction experiments designed to examine the effect of various experimental parameters on the extraction efficiency of heavy metals. The experimental results depicted that up to 30 min time for supramolecular ligand is enough for the significant extraction of all the metals under study. The pH level, slightly acidic to the neutral condition is favourable for maximum extraction of metals. The percent extraction at optimized conditions of time and pH were found to be 98.29, 96.63, 96.95 and 95.64% for Fe3+, Cd2+, Pb2+ and Zn2+ respectively. The extraction efficiency was governed by chloroform as a solvent. Simple to synthesize, faster extraction of metals, slightly acidic to neutral pH conditions for extraction are the characteristic features of the compound which governs its applicability.
Показать больше [+] Меньше [-]Impact of Carbon Nanotubes as Additives with Cotton Seed Biodiesel Blended with Diesel in Ci Engine - An Experimental Analysis
2020
G. Ninawe and M. Tariq
In the present global scenario, fossil fuels are facing challenges due to escalating costs, increasing demand and impact on environmental pollution. In internal combustion engines, the emission characteristics and economy of the fuel are controlled by the chemical and physical properties of the fuel. Various additives are being used to act like catalysts with the fuels to improve quality of fuel, to obtain better combustion and to reduce exhaust emissions. At the time of combustion process, fuel instability reactions get accelerated by the catalysts which improve the performance of the engine. In this study, the B10, B15 and B20 fuel blends of cotton seed oil and diesel were mixed with the carbon nanotubes (CNTs) as an additive to analyse the performance and exhaust emissions of a CI engine. The carbon nanotubes were mixed with each fuel blend with the concentration of 50 ppm. All the tests were carried out for different engine loads. Tested characteristics were power, brake thermal efficiency (BTE), specific fuel consumption (SFC), and analysis of exhaust gases like hydrocarbons (HC), CO2, CO, and smoke. The experimental results showed that there was significant reduction of SFC and improved combustion by addition of CNTs. It was also observed that the exhaust emissions, CO, HC, and smoke percentage got decreased by the influence of CNTs.
Показать больше [+] Меньше [-]Assessment of Agricultural Environmental Pollution Based on Fuzzy Comprehensive Evaluation: Case Study of the Yangtze River Economic Belt in China
2020
Honglei Huang
The Yangtze River Economic Belt is an important production area of grains, oil, livestock, and aquatic products across three regions in China; thus, its agricultural environment is of particular importance. However, the agricultural environment of the Yangtze River Economic Belt has been polluted for a long time by three industrial wastes, agricultural fertilizers, pesticides, and livestock wastes. Although effort to prevent and control pollution has been increased in recent years, the situation remains severe. The assessment of agricultural environmental pollution was explored by using fuzzy comprehensive evaluation and the data from the 11 provinces and cities in the Yangtze River Economic Belt in the period of 2008- 2016. The results show that agricultural environmental pollution in the Yangtze River Economic Belt is at a serious level on the basis of research on the current situation of such pollution, the use of relevant environmental pollution index data of the provinces and cities in the region from 2007 to 2016, and the performance of fuzzy comprehensive evaluation. Countermeasures to improve agricultural environmental pollution in the Yangtze River Economic Belt are proposed. They include strengthening the control of pollution caused by the three industrial wastes, pesticides, chemical fertilizers, and livestock) and the environmental education of farmers through various forms.
Показать больше [+] Меньше [-]Net Anthropogenic Nitrogen Input (NANI) Evolution and Total Nitrogen (TN) Concentration Response in Zhaoshandu Water Source
2020
A-long Li, Hai-tao Chen, Yuan-yuan Liu, Lin Qiu and Wen-chuan Wang
The nitrogen concentration/flux of water is very sensitive to the response of Net Anthropogenic Nitrogen Inputs (NANI), but the research on the dynamic response of nitrogen concentration to NANI is still rarely reported. In this study, the source of Zhaoshandu water source in Zhejiang Province, China, was used as the research object. The dynamic response of total nitrogen (TN) concentration to NANI in the basin was quantitatively analysed from 2005 to 2014. The results show that the NANI of the water source has a growing trend. It has increased by 6.73% in ten years. The average annual average of NANI is 85.76 kg (hm2·a-1), which is 1.7 times the national average of 2009. The average contribution rate of atmospheric nitrogen, chemical fertilizer nitrogen, food and feed nitrogen and crop fixed nitrogen is 40.98%, 34.06%, 20.25% and 4.7% respectively. The spatial difference of NANI is large, showing an increasing trend from the upstream mountainous area along the downstream. The sub-basin 2 is the key source of nitrogen pollution in this water source. NANI is the only independent variable of the TN concentration regression model with a variance interpretation rate of 55.4%. In the future, it is necessary to reduce the nitrogen input intensity of nitrogen, food and feed for chemical fertilizers as the main target, and to achieve the goal of water quality improvement by reducing the NANI intensity in the basin.
Показать больше [+] Меньше [-]Efficient Adsorptive Performance of Medical Stone Decorated by Carbon Dots
2020
Baolong Zhao, Leilei Hu, Hengjia Kang and Zhihong Zheng
Carbon dots could significantly change the property of a normal material and have received wide attention in the recent decade. In this research, glucose as a carbon source, carbon dots decorated medical stone (CD-MS) was successfully synthesized for efficient adsorptive removal of organic pollutants. Pyrolytic temperature and glucose concentration for the adsorbent preparation were proved to have a significant impact on the adsorptive performance. The optimal pyrolytic temperature and glucose concentration were found to be 300°C and 0.5 M, yielding the optimized adsorbent 0.5CD-MS-300 superior to other carbon dots decorated MS. Surface morphology analysis demonstrated that the carbon dots were successfully immobilized on the surface of MS while the atomic ratio of C increased from 2.6% of the raw MS to 11.25% of the 0.5CD-MS-300. Three organic pollutants including p-nitrophenol, orange II and methylene blue with different charge properties were employed to explore the adsorptive performance of the 0.5CD-MS-300. The results indicated that the surface of 0.5CD-MS-300 was negatively charged while carbon dots had significantly improved the adsorption capability of the raw MS. As such, the resulting adsorbent 0.5CD-MS-300 can be considered as a powerful adsorbent for the removal of some organic contaminants from wastewater.
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