Bioremoval of heavy metals by the use of microalgae pdf
Keywords Microalgae, Tetraselmis, Heavy metals, Bioremediation, Bioremediation INTRODUCTION Every day, industrial processes generate large amounts of contaminated water, which are discharged into the environment. EPS production and bioremoval of heavy metals by mixed and pure bacterial cultures isolated from Ankara Stream. With the use of clean electricity, electrocoagulation efficiently removes a wide range of contaminants with a single system. We are still far away from fully understanding how biotic and abiotic factors determine species occurrence, co-occurrence and distribution. How sublethal levels of antibiotics and heavy metals select for clinically important multidrug resistance plasmids is largely unknown. Bioremoval of metals by living algae 0 10 20 30 40 50 60 70 80 90 100 Cr Cu FeMnSe Zn Metals 10 mg/L 15 mg/L 20 mg/L 25 mg/L Percent Bioremoval 5 mg/L Fig.
accumulation of heavy metals  and can occur simultaneously for metals in different ionic states, cf. Abstract: Given that sustainable energy production and advanced wastewater treatment for producing clean water are two major challenges faced by modern society, microalgae make a desirable treatment alternative by providing a renewable biomass feedstock for biofuel production, while treating wastewater as a growth medium. The use of microalgae in biotechnological processes has received much attention worldwide. It is thought that tissues of some brown algae are able to tolerate relatively high levels of heavy metals and this increases their potential use as bio indicator for metal pollution. effective and environmental friendly approach like the use of biosorbents (such as the microalgae).
Microalgae can also serve as an indicator of water quality, with some strains proliferating in polluted water while others thrive in unpolluted water. Furthermore, the microalgae biosorbent was regenerated using 0.1 M HCl solution, with up to 80% In(iii) recovery, for several cycles. This encourages the investigation of biomolecular study of microalgae which absorb the heavy metals. Wastewater treatment method to remove heavy metal contaminants includes chemical precipitation, ion exchange, membrane, filtration, adsorption using activated carbon.
Heavy Metal Toxicity Heavy metals are elements having atomic weights between 63.5 and 200.6, and a specific gravity greater than 5.0.Most of the heavy metals are dangerous to health or to the environment. The use of higher plants and bacteria for bioextraction and bioremediation of heavy metals and organic pollutants have been extensively studied. Rising adoption of microalgae as supplements or natural colorants in various food products including, pizza, snack bars, drinks, and others is expected to aid the growth of microalgae food market. Compiled by a diverse team of experts, with experience in scientific and industrial fields, the Comprehensive Report for Wastewater Treatment Using Algae is the first report that provides in-depth analysis and insights on this important field. Furthermore, challenges and future prospects in bioremediation of heavy metals by microalgae are also explored. Textile industries consume an extensive and diverse array of chemicals in the form of dyes, dispersants, levelling agents, acids, alkalis, salts and sometimes heavy metals (7, 12).
They can serve as water bioremediation agents (), as feed for aquaculture (), as food for humans and animals (), in pigment production (), in bioremoval of heavy metals (), and in agriculture ().It is usually desirable to establish large populations of microalgae, especially in aquatic environments where they are often employed. Bioremoval of heavy metals from industrial effluent by fixed-bed column of red macroalgae. This review summarizes the current literature, highlighting the potential benefits and problems associated with the development of novel algal-based bioremoval processes for the abatement of heavy metal pollution. The discharge of untreated tannery wastewater containing biotoxic substances of heavy metals in the ecosystem is one of the most important environmental and health challenges in our society. This work confirms the potential use of a live microalgae Scenedesmus obliquus as an efficient technique for removing ions from wastewater. The persistence of heavy metals in the environment may pollute or contaminate soils and aqueous streams as both natural components or as the result of human activity. Phycoremediation has advantages over physic-chemical approaches as it is can completely degrade organic pollutants without destroy the surrounding flora and fauna. In appropriate conditions, 85% of copper(II), 70% of zinc(II) and 99% of aluminum(III) could be removed from solutions by tested microalgae within 20 minutes.
degree, the presence of heavy metals and high organic loads.
Biosorption using algae biomass can be an alternative method to eliminate heavy metals. Heavy metals contents resulted far below the threshold established by the European legislation on sludge spreading.
terms of environmental biotechnology, microalgae are useful for bioremediation of agro-industrial wastewater, and as a biological tool for assessment and monitoring of environmental toxicants such as heavy metals, pesticides and pharmaceuticals. The resulting biological ceramics (biocers) ought to combine the mechanical stability and porosity of the silicate matrix with the algae’s capability for the biosorption for heavy metals. This is primarily due to the fact that they are inexpensive to grow, requiring only sunlight and CO2, whilst lending themselves to a range of uses, such as to reduce CO2 levels, as fish feed, in biofuel production, for the generation of secondary metabolites of interest, and in bioremediation. The main mechanism to remove pollutants includes accumulating and/or using them in their cells (Hoffmann, 1998). Microalgae is generally produced in open ponds but for better control of the physical parameters closed photobioreactor is considered. In potato plants, we found the positive correlation between organ biomass and absorption and accumulation of heavy metals . Within this category, the use of microalgae has attracted the most attention , due to its ability to reduce the concentration of inorganic nutrients such as nitrogen and phosphorus    and decrease the concentration of dissolved heavy metals such as mercury , cadmium and copper , lead , aluminum , and chromium . This is due to affinity of algal surfaces for heavy metals leading to their adsorption and precipitation.
The aim of this study was to determine the growth efficiency and the bioremoval capacity of the green microalga, Botryococcus sp. Microalgae are so efficient at scavenging of metals from influent water, from contaminants in nutrients, or from atmospheric deposition into open ponds, that the biomass produced sometimes can contain amounts at the upper limit of metal content for food use (Kajan et al., 1992). Heavy metals also inhibit algal growth (Vasseur and Pandard, 1988) but this process was not . Algae fuel, algal biofuel, or algal oil is an alternative to liquid fossil fuels that uses algae as its source of energy-rich oils. The recycling of materials and use of wastes as sources of these key elements are not without problems. The use of microalgae for the bioremoval of heavy metals has been observed for last decades. Selectivity for In(iii) was also observed over other metals, such as Cu(ii), Zn(ii), and Al(iii).
Microalgae Heavy metals Bioremediation Mechanism abstract Biotechnology of microalgae has gained popularity due to the growing need for novel environmental technologies and the development of innovative mass-production. However, the usage of closed photobioreactor is expensive and consumes more energy. ABSTRACTThis study investigates the emission of a heavy-duty diesel engine generator fueled with waste cooking oil (WCO)-based biodiesel blends (W) and operated at 1.5 and 3.0 kW loads. Here, we review algal metabolism and cultivation; algal biomass conversion to biodiesel, bioethanol, biohydrogen, methane, electricity and fertilizers; and removal of metals with microalgae. CaCl2 pretreatment is the most suitable and economic method for activation of algal biomass. The structure, mechanical properties, and sorption capability of such algae-silicate materials were investigated.
The lower portions of the algal filaments attached to substrates allow regrowth to occur. It is essential to remove or reduce heavy metal contamination in order to prevent or reduce contaminating the environment. It enables you to deposit any research data (including raw and processed data, video, code, software, algorithms, protocols, and methods) associated with your research manuscript. When microalgae are on the stress of heavy metals, it will produce a series of physiological responses to response to environmental stress by itself.
Polyphosphate bodies have the ability to accumulate metals and also to protect algal cells from metal toxicity [8, 15]. heavy metals from aqueous solutions or from aqueous solutions that saturate soils; but yet, all of them remediate rather than prevent. Therefore it also has a detoxification mechanism in a certain concentration range, which has great significance for sewage treatment using microalgae. However, these wastewaters contained not only nutrients but also harmful heavy metals that threaten the aquatic life and public health. Conventional techniques to remove heavy metal are often ineffective and very expensive. Heavy metals constitute toxic, non-degradable and persistent environment pollutants which adversely affect the growth, development and survival of all life forms.
Removal of heavy metals from wastewaters using microalgae is gaining interest because microalgae also assimilate carbon, nitrogen and phosphorus. Via photosynthesis it could produce oxygen required for biological oxidation of organic matter. Read as many books as you like (Personal use) and Join Over 150.000 Happy Readers. We analyzed the resistance to some heavy metals by dry weight and plate: the fungus grew in 2000 ppm of zinc, lead, and mercury, 1200 and 1000 ppm of arsenic (III) and (VI), 800 ppm of fluor and cobalt, and least in cadmium (400 ppm).
Citations Publications citing this paper.
Uptake of metals by living microalgae occurs in two steps: one takes place rapidly and is essentially independent of cell metabolism – “adsorption” onto the cell surface. Of these chemicals, the most common nutrient limiting ones are nitrogen and phosphorus (Larsdotter 2006). Removals of nitrogen, phosphorus and heavy metals from hy wastewater by bioremvoal.
The major drawback in the production of biofuels from the microalgae is the limited amount of algal biomass is produced. International Journal of Phytoremediation 18 4: Handbook of microalgal culture: Bioremoval, the use of biological systems for the removal of metal ions from polluted waters, has the potential to achieve greater performance at lower cost than conventional wastewater treatment technologies for metal removal.
The use of biological methods such as bioaccumulation and biosorption is suitable for the removal of pollutants from wastewaters. Bioremoval of heavy metals by the use of microalgae International Journal of Phytoremediation 18 4: Advances in Experimental Medicine and Biology Although microalgae are not unique in their bioremoval capabilities, they offer advantages over other biological materials in some conceptual bioremoval process schemes. other heavy metals such as nickel, mercury, copper, zinc, and chromium that inhibit algal alkaline phosphatase. Tolerance and response of different microalgae strains to heavy metals and their bioaccumulation capability with value-added by-products formation as well as utilization of non-living biomass as biosorbents are discussed. As discussed previously, conjugation of heavy metals to phytochelatin is a primary means of detoxifying heavy metals in plants and algae. The alternative to current system could be microalgae treatment step, which would use green algae to consume pollutants present in the waste water, namely nitrogen, phosphorus and heavy metals. The results indicated some potential differences in the Cr(VI) removal mechanism at different experimental conditions. These tolerant algae protect themselves from metal toxicity by producing access amount of some secondary metabolites and fatty acids, amino-acids and hydrocarbons.
The exact role of vacuoles in heavy-metal detoxification is not yet clear, but vacuolation could contribute to compartmentalization of toxic metals, as suggested by Davies et al. The book is about Microalgae Biotechnology for development of biofuel and wastewater treatment.
Heavy metals are usually present in wastewaters in dilute quantities (1 - 100 mg/L) and at neutral or acidic pH values (< 7.0). Discharging wastewater containing heavy metals of Cu, Pb, Zn and Cd into water bodies can cause toxicity in plants and aquatic animals and some of them will be unable to survive except algae. Saline wastewater contains numerous pollutants such as nutrients, heavy metals, micropollutants, and organic pollutants. A brand of pure fossil diesel was adopted as the base fuel, with 20% and 40% WCO-based biodiesel added into the based fuel to form W20 and W40 blends, respectively. Bioremediation process in this regards is an option that offers the possibility to destroy or render harmless various contaminants using plants and microbes. Another advantage of the use of the algae in phytoremediation is the high biomass production by these species leading to high absorption and accumulation of heavy metals. 33 Microalgae for Aquaculture: The Current Global Situation and Future Trends 615 Arnaud Muller-Feuga.
These organisms often exhibit specificity for particular metals.
and microalgae, have been tested for their ability to accumulate heavy metals or dyes. Bioremediation of heavy metals by using the microalga Desmodesmus subspicatus Bachelor´s Thesis, 91 pages, appendices 17 pages August 2014 All around the world natural water bodies are contaminated with heavy metals from previous and recent mining activities. The mechanism of heavy metals uptake through water may explain this influence of pH and salinity on the lethal toxicity detected. Algae-silica hybrid materials for biosorption purposes were prepared using sol-gel technology. Some contaminants, present accidentally in drinking water, are very difficult to remove, such as heavy elements that are products of industrial waste.