Removal of two cationic dyes from a textile effluent by filtration-adsorption on wood sawdust

BACKGROUND: Wastewater from textile industry contains various contaminants such as dyes, surfactants and heavy metals. Textile dyes have synthetic origin and complex aromatic molecular structures that make them difficult to biodegrade when discharged in the ecosystem. The objective of this study was to examine the decolourisation of textile effluents containing cationic dyes by filtration-adsorption on wood sawdust from two different origins; fir as an example of a conifer tree, and beech as an example of a deciduous one, and to explain the adsorption mechanism. METHODS: The process of dye removal was applied to a synthetic effluent in batch mode. Adsorption experiments were performed by suspending sawdust in the effluent and analyzing the supernatant by spectrophotometry. The effectiveness of the treatment process was evaluated by measuring coloration. RESULTS AND DISCUSSION: Experimental results showed a significant potential for wood sawdust, especially coniferous sawdust, to remove cationic dyes from textile effluents. Adsorption kinetics was influenced by the initial dye concentration, nature and amount of sorbent as well as sorbent particle size. The adsorption followed a pseudo first-order kinetics. For both basic dyes, the Langmuir adsorption equation showed a better fit than the Freundlich equation. CONCLUSION: Filtration-adsorption using an inexpensive and readily available biosorbent provided an attractive alternative treatment for dye removal, and it does not generate any secondary pollution. Recommendations and Perspectives. Laboratory studies provide promising perspectives for the utilization of wood sawdust as renewable adsorbent for reducing pollution while enhancing the reuse of textile effluents. However, the treatment process needs to be applied to the other textile dye classes in order to be used on an industrial scale.     

Economic potential of recycling business in Lahore, Pakistan

The state of household waste recycling in Lahore city, Pakistan with a population of 7.2 million was analyzed. Data on solid waste recycling were gathered from residents of low-, middle- and high-income groups, as well as from scavengers and junkshops. The recycling activities in Lahore exert a significant impact on resource conservation, creation of jobs, provision of economic opportunity and reduction in the magnitude of waste disposal problems. A cost analysis is presented to show the income that can be generated through a well-planned recycling program. It is shown that 21.2% of all recyclable waste in Lahore is recycled, and it generates an amount of Rs. 271 million (US dollars 4.5 million) per year through the informal sector. However, if the recycling practice is owned by the formal sector, it can save an amount of Rs. 65 million by reducing the collection cost. If recycling is adopted as an industry, it can generate revenues of Rs. 530 million (US dollars 8.8 million) per year and can also save enormous amount of energy, as well as the natural resources.     

Effect of chromium on growth attributes in sunflower (Helianthus annuus L.)

Heavy metal soil pollution takes place when the metal concentration of soil exceeds natural background level and causes ecological destruction and deterioration of the environment.In the present study,a pot experiment was conducted to evaluate the effect of chromium-contaminated soil in sunflower(Helianthus annuus L.)growth attributes.Three different levels of chromium(Cr)i.e.,20, 40,and 60 mg/kg were applied to three varieties of sunflower(G-3,G-9,and G-59).The results of morphological,chemical,and yield p...     

The mediating role of ICTs in the relationship between international tourism and environmental degradation: fit as a fiddle

Environmental Science and Pollution Research - The United Nations sustainable development goals (SDGs) proposed 17 effective plans linked with three principal aims, i.e., eradicating poverty,...     

Analysing economic impact on interdependent infrastructure after flood: Pakistan a case in point

A disaster such as floods can have a drastic impact on interdependent infrastructure and economic sectors. The resilience or the ability of the critical sector to recover quickly from the disruption can also reduce the consequences of the disaster. In this paper, through resilience and recovery time Dynamic Inoperability Input-Output model (DIIM) is applied. Thus, Input-Output (I-O) table is constructed for Pakistan's economic system and a case study is performed on the flooding in Pakistan 2011–12. The purpose of this study is to provide a ballpark estimate of the system-wide impact and ripple effect on the sectors that lasted for several days after the disruption. Furthermore, to analyze the inoperability and economic loss in the sectors caused by the disaster in a developing country. The findings of the research show that most of the critical sectors are associated with agriculture and service sector in terms of inoperability and economic loss respectively. The outcome of the study will be essential for the policy makers, disaster management authorities and health departments to respond accordingly.     

Modeling a sustainable Saudi Arabian economy: the real issues

This paper develops a macroeconomic framework for creating a competitive and sustainable Saudi Arabian economy, taking into account the interrelationships among social, environmental, and economic factors. The objective of the research is to build a model that will allow for evaluating the effects of a wide range of emissions abatement policies on economic growth and development. The research methodology is grounded in econometric modeling of the Saudi economy over the period 1980–2010. The estimated parameters of the model were used to project long-term gross domestic product (GDP) growth paths based on three environmental degradation abatement scenarios. The results suggest that the sustainability of economic growth in Saudi Arabia critically depends on aggressive emissions-reduction policies since policy scenarios corresponding to higher pollution cuts yielded higher, sustained long-term GDP. The results also broadly reject the Environmental Kuznets Curve (EKC) hypothesis, implying that a turning point in the relationship between CO₂ emissions and per capita GDP is yet to be attained.     

The relationship between air pollution,fossil fuel energy consumption,and water resources in the panel of selected Asia-Pacific countries

The objective of the study is to examine the relationship between air pollution, fossil fuel energy consumption, water resources, and natural resource rents in the panel of selected Asia-Pacific countries, over a period of 1975–2012. The study includes number of variables in the model for robust analysis. The results of cross-sectional analysis show that there is a significant relationship between air pollution, energy consumption, and water productivity in the individual countries of Asia-Pacific. However, the results of each country vary according to the time invariant shocks. For this purpose, the study employed the panel least square technique which includes the panel least square regression, panel fixed effect regression, and panel two-stage least square regression. In general, all the panel tests indicate that there is a significant and positive relationship between air pollution, energy consumption, and water resources in the region. The fossil fuel energy consumption has a major dominating impact on the changes in the air pollution in the region.     

Epoxidised Natural Rubber Filled Spent Coffee Ground Green Biocomposites

Journal of Polymers and the Environment - This study investigates the influence of spent coffee (SC), and potassium hydroxide (KOH) modified spent coffee (ACT-SC) as fillers on the mechanical and...     

Does globalization affect the green economy and environment? The relationship between energy consumption,carbon dioxide emissions,and economic growth

Environmental Science and Pollution Research - This study analyzes the relationship between globalization, energy consumption, and economic growth among selected South Asian countries to promote...