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Biochar is a stabilized, carbon-rich by-product derived from pyrolysis of biomass. Recently, biochar has received extensive attentions because of its multi-functionality for agricultural and environmental applications. Biochar can contribute to sequestration of atmosphere carbon, improvement of soils quality, and mitigation of environmental contaminations. The capability of biochar for specific application is determined by its properties which are predominantly controlled by source material and pyrolysis route variables. The biochar sorption potential is a function of its surface area, pores volume, ash contents, and functional groups. The impacts of each production factors on these characteristics of biochar need to be well-understood to design efficient biochars for pesticides removal. The effects of biomass type on biochar sorptive properties are determined by relative amounts of its lingo-cellulosic compounds, minerals content, particles size, and structure. The highest treatment temperature is the most effective pyrolysis factor in the determination of biochar sorption behavior. The expansion of micro-porosity and surface area and also increase of biochar organic carbon content and hydrophobicity mostly happen by pyrolysis peak temperature rise. These changes make biochar suitable for immobilization of organic contaminants. Heating rate, gas pressure, and reaction retention time after the pyrolysis temperatures are sequentially important pyrolysis variables effective on biochar sorptive properties. This review compiles the available knowledge about the impacts of production variables on biochars sorptive properties and discusses the aging process as the main factor in post-pyrolysis alterations of biochars sorption capacity. The drawbacks of biochar application in the environment are summarized as well in the last section.

Changes in crude oil production and distribution have increased the incidence of oil spills throughout the world. Oil spills often cause destructive effects on aquatic and land ecosystems. The oil spill cleanup and recovery techniques are challenging and usually involve complex mechanical, chemical, and biological methods. Usually, mechanical removal of free oil is utilized as an effective strategy for cleanup in aquatic and terrestrial environments; however, they are expensive and need specialist personnel and equipment. The other commonly used method is the application of chemical materials such as dispersants, cleaners, demulsifiers, biosurfactants, and soil oxidizers. Nevertheless, these reagents can have potential harmful environmental impacts, which may limit their application. As an alternative, bioremediation can offer reduced environment risk; however, the limitations of microbial activity in the soil can make this option unsuitable. One area of bioremediation is phytoremediation, which offers potential for restoring large areas of contaminated ground. Plants are able to remove pollutants through processes such as biodegradation, phytovolatilization, accumulation, and metabolic transformation. This review presents the fate of crude oil spills in aquatic and land ecosystems and their environmental effects. Furthermore, the paper focuses on crude oil phytoremediation and its applications in polluted ecosystems.

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Characteristics and efficiency of wasted black tea (WBT) were investigated as a low-cost sorbent in removal of Ni 2+ and Zn 2+ ions from aqueous solution. Initial findings showed WBT potential to be applied as an effective sorbent due to high concentrations of carbon and calcium and high porosity and availability of functional groups. Sorption dynamics were studied with varying pH, contact time, and adsorbent dose. Maximum percentages of metal ions removal were recorded at pH 5, contact time 250 min, and 20 g/L of adsorbent concentration. Binary metal sorption studies showed that Ni 2+ and Zn 2+ do not compete with each other for available sorption sites, so the adsorption trend in binary system appears similar to monocomponent metal adsorption. Evaluation of the isotherms confirmed that WBT has high value of adsorption capacity. Sorption data fitted well with both Freundlich and Langmuir models. In the optimum conditions, maximum capacity of WBT could reach up to 90.91 mg-Ni/g adsorbent and 166.67 mg-Zn/g adsorbent. This experiment demonstrated the ability of tea waste as an effective, sustainable, and low-cost adsorbent for removal of the heavy metal ions.

Problem statement: In many countries such as Malaysia, it is increasingly more difficult to find suitable locations for landfills, which are accepted by the population. These circumstances are to be found all over the world and make new strategies for waste management necessary. Approach: Integrated Solid Waste Management (ISWM) systems are one of the greatest challenges for sustainable development. But for any ISWM system to be successful, the first step is to carry out waste characterization studies. Therefore, the study was conducted to characterize the quality and quantity of generated solid waste at University Technology PETRONAS (UTP) academic buildings to suggest a recycling system with emphasis on recycling container size and arrangement. Results: Initially, a survey was conducted to highlight the existing situation of recycling activities and recycle bins condition in the campus. Then, six different sampling points were selected at campus academic complex and solid waste from those points was characterized for both term-time and semester break periods. Procedure of sampling involved unloading and analyzing a quantity of produced daily waste at each building in a controlled area. The integrity of all received waste was maintained regardless of the odor or physical decay. While survey outcomes shows that 80% of students and staff were interested to take part in recycling activities only 53% of them have practiced in it and the main reasons were that 75 and 83% of them could not find suitable and enough number of recycle bin, respectively. In another development it was obtained that up to 80% of produced materials at academic building are recyclable while paper percentage is predominant with 40% and 33% during term-time and semester break, respectively. Food waste was detected in all samples which could lead cross contamination, value drop and development of odor and flies. The solid waste generation was varied between 8.8-2.4 kg day^-1 in term-time and semester break, respectively. Conclusion/Recommendations: These results showed providing suitable and enough number of recycling bins would encourage more people to participate in recycling activities. This will lead to more efficient waste segregation and reduction of waste load to the landfills. Therefore, a small or medium size three-compartment container system is suggested to be used in academic building of the campus which collects all paper and cardboard in first container, all plastic, glass, tin cans, aluminum and any other metals in second container and food waste in the third container

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