Powder Surface Area and Porosity (Environmental Resource Management Series)

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Seller Inventory GRP Lastly, the pressure difference between the laboratory and corridor was also measured using a pocket manometer Furness Controls Ltd. In order to facilitate the mold identification, colonies with different morphology were separated and sub-cultured on PDA plates until sporulation. The spore forming structure was examined under a microscope to identify the mold to the genus level, if possible, to narrow down the selection of species-specific primers for further identification [ 9 , 10 ].

Shenzhen, China. Primers used in this study are listed in Table 1. Primers used for mold identification in this study [ 9 , 10 ]. The mold speciation is an indication of the diversity of the physical environment e. Combining the mold information and the on-site environmental features, different contamination scenarios were deduced. Dew point was calculated to predict the temperature and RH conditions that cause condensation [ 11 ].

Other experimental data and models for mold growth, e. Information about the contaminated areas and their environmental conditions are presented in Figure 2 and Table 2. In total, eight contaminated areas were identified, and all the contaminated surfaces had a higher a w than the room RH In aggregate, seven species were isolated—two Cladosporium spp.

Cladosporium cladosporioides and Cladosporium halotolerans , two Aspergillus spp. Except for C. Laboratory layout and sample sites. The arrows in the laboratory indicate the air flow direction. The downward arrow on the left indicates the supply air coming out from the air diffusers and the upward arrow on the right points to the direction of the return air into the air-cooling units. The arrows shown outside the laboratory indicate the movement of the air into the laboratory.

The room on the left of the laboratory is for the lab attendant and on right for the scientific officers. There are windows at the back of the laboratory. The windows are always kept closed. A total of cm 2 mold patch area was observed on the anti-mold painted cement brick wall M The wall surface had the highest a w of 0. The surface temperature was The light level on the wall surface was dim because the wall is under a wall cabinet Figure 2.

According to the laboratory user, a larger contaminated surface than that we reported was observed before cleaning with diluted household chlorine bleach about 2—3 months ago. According to the Estate Office, an anti-mold paint was applied onto the wall, but our results show that this paint could not guarantee a mold free environment.

The mold density was relatively low 0. The room behind the wall is occupied by a laboratory attendant. Due to its functional purpose, this room is always air-conditioned to maintain a stable temperature at The door of the laboratory is also located on this side and faces a corridor that is used by the laboratory and office users.

The door of the corridor opens to the outdoor environment. At the time of the investigation, the RH of the corridor outside the laboratory was The air pressure in the corridor was 5 Pa higher than that in the laboratory indicating air infiltrated from the corridor into the laboratory. Part of the bench surface M close to the contaminated wall M was infested as well cm 2 with the second highest a w of 0.

It was dominated by C. Figure 3. Two metal surfaces, water bath M and shaker M had the lowest surface temperature of Both surfaces had a water activity level of 0. These instruments were located on the left and middle benches and received a similar room light level Figure 2. The water bath was used occasionally and thus dusty. The molds on the metal surface had been cleaned with bleach before but molds were found again at the time of sampling. The mold density was the lowest 0.

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Two species of molds, A. The mold density was about 0. The other two contaminated objects near the shaker were the packing film plastic material wrapped around a Benchguard box M and a plastic mineral oil box M The packing film had a water activity of 0. It was hidden under a cupboard and had never been used, hence it was very dusty. Isolates included C. The mineral oil box M had a similar a w 0. It was placed in the same cupboard as the packing film and was dusty.

A low mold density 0. A plastic toolbox M located the back of a bench and next to a window was also contaminated by molds on the top surface Figure 2. Due to its placement, the toolbox received room light and sunlight. The box was covered by dust since it was rarely used.

The highest number of molds 5 species was isolated including C. Finally, molds contaminated the back of an analytical balance M The balance was the only mold-contaminated item on the right side of the laboratory Figure 2. It had the lowest a w 0. Tritirachium sp. On the right side of the laboratory, there is an office for 10 people and the air conditioning was operated in the same pattern as the laboratory 18 h operation and turned off throughout the weekend. Figure 4 summarizes the occurrence percentage of the isolated molds in the laboratory.

Both Cladosporium spp. Together with A. Table 3 presents the ecological niches and growth requirements of the isolated species which provided information to develop the mold contamination scenarios in each contaminated area. It was reported that C. Aspergillus spp. There are limited studies about the ecological and physiological features of Tritirachium. It has been isolated from the sea, plant and soil [ 22 ]. It is not a common indoor mold.

Rhizopus is a genus that generally needs a a w of above 0. Rhizopus spp. Isolation from aluminum foil in water-damaged building was also reported [ 24 ], which implies that T. Apart from the surface texture of building materials, it was pointed out that a poor state of maintenance, aging, loading wear and tear on the material , limited cleaning access and dirt are indicators of the capability of a material to support mold growth [ 26 ].

Gravesen et al. Based on the mold speciation and environmental conditions, the mold contamination scenarios were deduced. The presence of T. Water condensation was likely on this wall because the adjacent room kept air-conditioning while the air-conditioning was off after working hours in the laboratory. This cooler wall surface as compared to the room air was prone to condensation. The laboratory door is near to this wall. The infiltrated hot and humid air could easily condense on this surface.

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Powder Surface Area and Porosity S. Lowell PhD Quantachrome Corporation, USAJoan E. Shields PhD C. W. Post Center of L. ykoketomel.ml: Powder Surface Area and Porosity (Environmental Resource Management Series) () by Seymour Lowell and a great selection .

The high abundance of Cladosporium spp. This may be associated with the lower a w of the bench surface than the wall a w 0. The bench was dusty which may support the mold growth even at a low a w because the dust may create a hygroscopic environment to absorb moisture and provide nutrients. The water bath M was slightly contaminated by C. Organic matter on the water bath surface is one of the important requirements for mold growth on metal surface. In addition, the water bath was close to the door and its position increased the chances of condensation on the water bath surface.

Interestingly, the shaker M was the only area that without Cladosporium spp. These results imply that this contamination area had a low a w that can only support the primary colonizer. Metal surface is unfavorable for mold growth because of the non-porous texture and lack of nutrients. Therefore, the presence of organic matter is critical to support the mold growth. The shaker did not look dusty but the flasks placed in the shaker could carry dirt that provided nutrients to certain areas.

The process of removal of adsorbed substance from the surface on which it is adsorbed is called desorption. It is the reverse of adsorption and can be brought about by heating or by reducing the pressure. Adsorption is quite different from another similar sounding process called absorption in which substances diffuse into some bulk phase-solid, liquid or gaseous Adsorption, as a process has wide industrial applications and is even operative in many physical, chemical, biological and natural systems.

It is a surface phenomenon and occurs due to the unbalanced forces on the surface of the solids and liquids. If we consider a solid, it is examined that a molecule present in the bulk of the solid is being uniformly engrossed from all sides by the neighboring molecules As a result, there is no net attraction on this molecule. However, a molecule which lies near the surface known as a surface molecule is attracted only by molecules below it.

Therefore, surface molecules experience a resultant downward attractive force within the solid or liquid As a result, the surface of solid or liquid tends to satisfy their residual forces by attracting and retaining the molecules of other species a gas or dissolved substance when brought in contact with them.

Thus the phenomenon of higher concentration of molecular species gases or liquids on the surface of a solid than in the bulk is called adsorption 65 Table 2. Various researcher primed starch-based polymers by a cross linking reaction of starch-enriched flour using epichlorohydrin as a cross linking agent in the presence of NH 4 OH. The yield, mobility and structural properties of cross linked starch materials with various compositions were investigated and found a correlation between the structure, mobility and degree of cross linking of these sorbents.

The cross linked starch-based materials, containing tertiary amine groups were used for the recovery of various dyes from wastewater. It is recommended that the sorption mechanism was correlated to the structure of the polymer. One of the most important characteristics of an adsorbent is the quantity of solute it can be accumulated which was usually calculated from the adsorption isotherms. Dyes that are difficult to breakdown biologically, can often be removed by using the various adsorbent.

A good adsorbent should generally possess a porous structure which resulting in high surface area and the time taken for adsorption equilibrium to be established should be as small as possible so that it can be used to remove dye wastes in lesser time. Alumina has been tested by various workers for the removal of dyes Silica gel, prepared by the coagulation of colloidal silicic acid resulted in the formation of porous and noncrystalline granules of different sizes.

Adsorption capacity of adsorbent is defined as mass of solute adsorbed per unit mass of adsorbent and nature of adsorption can be described by relating the adsorption capacity to equilibrium concentration of the solute remaining in the solution using various isotherms Data were tested for suitability of isotherms such as Langmuir, Freundlich and Temkin.

Langmuir isotherm assumes that the adsorption takes place at specific homogeneous sites within the adsorbent. Additionally, isotherm may be expressed in terms of separation factor R L which is a dimensionless constant and can be determined by the following Eq. Freundlich isotherm is derived by assuming heterogeneous surface with a non-distribution of heat of adsorption over the surface.

The linear form of the Freundlich isotherm is expressed by Eq. Temkin isotherm suggested that the heat of adsorption of all molecules in layer decreases linearly with coverage due to adsorbent-adsorbate interactions and the adsorption is characterized by a uniform distribution of the bonding energies, upto maximum binding energy.

Temkin isotherm is represented by Eq. Controlling parameters during adsorption process Effect of temperature: The adsorption process for dye removal is dependent on an important variable called temperature. Nigam et al. This might be due to rise in the motion of dye molecules. Akhtar et al. This might be attributed to the alterations in the structure of the biomass. Bulut et al. The process was endothermic in nature. Temperature has two main effects on the surface adsorption process. Increasing the temperature is thought to accelerate the rate of diffusion of the adsorbate molecules across the external boundary layer and within the internal pores of the adsorbent particles as results of the reduced viscosity of the solution Furthermore, changing the temperature, changes the point of equilibrium of the reaction between adsorbent and the selected adsorbate.

Studying the dependence of the adsorption processes on the temperature variation has considerable importance regarding the physical property and entropy changes related to surface assimilation Gundoan et al. Upto the point of equilibrium rate of dye removal showed a direct relation with increase in temperature indicating a kinetically controlled process, as found in many other systems The mobility of molecules increases normally with increase in temperature, thus facilitating the formation of surface monolayer.

They found an inverse relation between adsorption of dye and increase in temperature, establishing that adsorption process was unfavorable at higher temperatures. Decreased sorption capacity of the adsorbent with increasing temperature was an indication of the exothermic nature of the adsorption process. Sharma and Bhattacharyya studied the effect of temperature on the removal of congo red dye by Azadirachta indica leaf powder.

With an increase in temperature, the adsorption of the dye molecules decreased, as the adsorbate separated from the solid surface to enter the liquid phase thereby decreasing the adsorption capacity. Effect of pH of the solution: The pH of the aqueous solution has been established as one of the most important factors influencing the adsorption kinetics.

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It influences not only the degree of ionization of the solute, the surface charge of the adsorbent and dissociation of functional groups on the active sites of the adsorbent, but also dye chemistry in the solution Chowdhury and Saha investigated the pH dependency of MG adsorption by alkali treated fly ash.

The initial pH of the solution was adjusted by using 0. The maximum adsorption capacity was obtained at pH 6. The profile of pH indicates that MG is one of the cationic dyes, it adsorbs to the adsorbent surface at higher pH values. The protonation of the dye takes place at low pH which results in low adsorption of dye in acidic medium. The removal of dye is inhibited at low pH values, mainly due to the increased competition between protons and dye molecules for the same binding sites.

With an increase in pH of the solution, the dye becomes more deprotonated; thereby increasing the negative charge density on the surface of the adsorbent thus, efficient removal of dye is observed when the pH of the solution is increased The pH of the solution substantially influences the adsorption of dye molecule due to change in the surface properties of the adsorbent. The solubility of dye is mainly affected by change in pH concentration of the solution.

Namasivayam and Kavitha examined the effect of pH on the removal of direct dye Congo red by using orange peel as an adsorbent. The maximum removal It is concluded that more removal is obtained in acidic pH of the direct dye solution. In another study, Namasivayam and Kavitha utilized activated carbon prepared from coir pith as a suitable adsorbent for the removal of congo red dye. They studied the effect of varying pH on the rate of removal. In highly acidic condition pH 2. At pH 4. The researchers explained that the observed effects could be attributed to the electrostatic attraction between positively charged binding sites on the adsorbent and negative charge bearing dye molecules or to a chemical reaction between biomass and dye.

At high pH values, the binding sites of the adsorbent become negatively charged which did not allow the adsorption of dye due to repulsion. Sharma and Bhattacharyya studied the removal of congo red dye by neem leaf powder. Their findings showed that the uptake of the congo red dye increased when the pH of the solution was increased from 4.

They also concluded that maximum interaction between the surface of neem leaf powder and dye molecules was observed near pH 7. The effect of pH variation on adsorption of three dyes namely: Amaranth, sunset yellow and fast green FCF by powdered peanut hull was studied by Gong et al. Gupta et al.

Toxicity of Disperse Dyes and its Removal from Wastewater Using Various Adsorbents: A Review

They observed a significantly high electrostatic repulsion existing between the positively charged surfaces of the adsorbent and dye molecules in acidic conditions. This considerably decreased the adsorption capacity of the adsorbent at low pH values, especially at values lower than 6. When the pH of the solution was increased from 6. Increasing the pH beyond 7. Effect of adsorbent dose: The methylene blue adsorption at a contact time of 2 h was studied by varying the adsorbent montmorillonite clay MC dose from 1. It is observed that the percentage removal of methylene blue increased with the increasing adsorbent concentration.

An increase in concentration of MC facilitated increased adsorption of methylene blue due to the availability of a greater number of possible binding sites resulting from increased surface area of MC. Tor et al. The percentage removal increased when the adsorbent dose was increased and equilibrium was attained at the adsorbent dose of 1. A possible explanation for this increase in adsorption capacity comes from the increase in the number of available adsorption sites that allow the binding of a greater number of dye molecules onto the surface of adsorbent.

Since, increasing the adsorbent dose beyond 1. Variation in adsorbent dose is an important factor because it explains the removal capabilities of adsorbent for a meticulous dye concentration. The effect of varying the adsorbent dose on the removal of congo red direct dye was evaluated by Namasivayam et al. The results showed that when adsorbent dose was increased, the percent uptake of dye also increased. The optimum dose 0. This can be attributed to the presence of large surface area of the adsorbent for the given mass.

Sharma and Bhattacharyya also studied the effect of adsorbent dose on the removal of congo red dye. The dye removal was maximum at low adsorbent dose of neem leaf powder because the low amount of neem leaf powder showed good relations with dye molecules. Namasivayam et al. They also showed that the maximum percentage removal was obtained at a high adsorbent dose.

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Gong et al. The rate of dye removal was found to increase with increase in the adsorbent dose.

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It was due to the presence of more exchanging sites on the adsorbent surface which facilitated greater removal of dyes. On the other hand, Namasivayam et al. In case of high adsorbent dose, the maximum percentage removal was observed. Effect of adsorbate concentration: The concentration of adsorbate is also an important variable affecting the adsorption process.

In general, an increase in the adsorption of dyes with increase in dye concentration is observed. This demonstrates that the increase or decrease of dye adsorption depends on the initial dye concentration. They observed that the removal percentage decreased from Such accumulation decreases the total surface area of the adsorbent particles available for adsorption of dyes. Mall et al. They observed an increase in the amount of dye adsorbed with the increasing initial dye concentration due to increase in the driving forces to overcome mass transfer resistance of the dye between the aquatic and solid phases.

However the study also concluded that the percentage removal of congo red dye decreased with the increase in dye concentration. The effect of varying the initial concentration of 2,4-dichlorophenol onto rice husk was illustrated by Akhtar et al. The initial dye concentration was increased from 0.

This might be attributed to the smaller number of binding sites available for the adsorption of a huge number of dye molecules. They supported their observations explaining that the binding sites on the surface of the adsorbent remain unsaturated during the initial stages of the adsorption process. The effect of initial dye concentration on the removal of direct red 80 by almond shells was investigated by Ardejani et al. It is showed that the percentage removal of direct red 80 dye decreased from Jain and Sikarwar also concluded that amount of dye adsorbed per unit mass of the biomass increased with increase in the dye concentration.

However, the percentage removal was higher at low initial dye concentration, indicating that the initial dye concentration significantly affected the adsorption of direct yellow 12 dye. In yet another study different concentration of direct brown and direct brown 2 dyes were used 85 to analyze the effect of initial dye concentration on the amount of dye adsorbed.

They observed that with the increase in the initial dye concentration, the amount of dye adsorbed also increased. It is proposed that the initial dye concentration significantly affected the adsorption potential of MC. At maximum solution concentrations, viz. These changes in equilibrium indicate the occurrence of a chemisorptions process at the surface of the MC in the initial stages of the experiment, followed by a second adsorbate layer in the later stages, whereas the adsorption capacity decreases in the final stage, thus resulting in dimerization of methylene blue dye at high concentrations.

The ionic nature of methylene blue dye could be responsible for the observed behavior, leading to one or more reactions over and above the primary adsorption phenomena Chowdhury and Saha found that absorption potential of treated fly ash was a function of dye concentration. The sudden profile of the curves obtained at the beginning of the experiment showed that the rate of adsorption was high, suggesting the appropriateness of Ca OH 2 treated fly ash for the treatment of very dilute dye solutions.

It was also observed that the rate of adsorption increased quickly in the starting and became slow in the end. Initial faster rates of adsorption were due to the availability of more binding sites for adsorption and the slower rates of adsorption at the end were due to the saturation of the binding sites and attainment of equilibrium.

However, the percentage of sorption decreases with the increase in initial dye concentration. It is explained that the limited number of active sites on the adsorbent become saturated at a definite concentration. This establishes that the adsorption capacity is bound to increase with the increase in initial dye concentration mainly due to the rise in mass transfer from the concentration gradient.

Effect of agitation speed: The strong dependence of adsorption process on agitation speed emanates from the facilitated mixing of solute in the solvent and the formation of the external boundary film. Shiau and Pan 88 studied the effect of agitation speed on film thickness for adsorption process. They conducted a series of experiments at various agitation rates rpm to study the adsorption of Basic green 5 on activated clay and observed that the rate of adsorption was highly affected by the degree of agitation when the agitation speed was increased from rpm.

On increasing the agitation rate beyond rpm, the adsorption rate showed slight variations indicating that the film thickness had no significant effect beyond the agitation speed of rpm. Patel and Vashi 35 predicted that the continuous increment in percentage removal of dye was observed with increasing agitation speed up to rpm and equilibrium was achieved at rpm. Increasing the agitation speed beyond rpm showed no effect on rate of adsorption. An increased adsorption rate at higher agitation speeds was probably due to increased mobility of adsorbate molecules.

This can be explained by the fact that increasing the agitation speed increases the external film transfer coefficient by reducing the film boundary layer between dye molecules and surrounding particles Kisku et al. The rate of removal for both dyes increased as agitation speed was increased up to rpm.

Disperse blue and disperse orange 25 both showed maximum removal at rpm. However, the net removal i. Tiwari et al. Both the dyes showed maximum removal at rpm. The net removal i. Albroomi et al. They conducted a number of experiments at various degrees of agitation rpm for the adsorption of methylene blue and azo dye tartrazine on activated carbon. The results indicated that the rate of agitation influenced the removal efficiency when the agitation speed was increased from rpm.

At agitation rates higher than rpm the removal efficiency showed very slight variation for the adsorption of methylene blue dye, indicating the negligible effect of film thickness beyond the agitation speed of rpm, therefore, the agitation rate of rpm was selected as the optimum value for all the future experiments.

Effect of contact time: Contact time is another important parameter which has been found to affect the sorption process significantly. It is revealed that the percentage adsorption increased initially for first 60 min and thereafter rate of removal slowed down.

The equilibrium was seen at 90 min. The equilibrium condition was achieved at contact times in between min. Thereafter with further increase in contact time the removal 2,4-dichlorophenol was almost stagnant. Ahmad et al. The equilibrium condition was achieved after 1 h of contact time. At first, rate of adsorption was high due to adsorption of dye molecules on the upper surface of palm ash. Then the rate decreased as the dye molecules penetrated into the inner porous structure of the palm ash. Wheat shells have also been used as an adsorbent for the uptake of direct blue 71 dye to find the effect of agitation time Bulut et al.

The equilibrium condition was found after 36 h. Ardejani et al. The percent removal was initially fast and then became almost stagnant as the time passed. Mohan et al. The uptake of dye was rapid in the beginning and then became almost constant at equilibrium point.

The removal of dye was rapid in the initial stages of the process due to association of binding sites on the biomass. Khaled et al. In the beginning, the high rate of adsorption might be ascribed to the presence of positive charge on the orange peel carbon which developed an interaction with negatively charged direct yellow 12 dye.

Finally, the rate of adsorption began to slow down after 20 min due to slow movement of dye molecule into the interior of bulk of the orange peel carbon and equilibrium condition was reached after 2 h. The adsorption of direct N-blue dye was studied by El Nemr et al. Kurniawan et al. The equilibrium adsorption capacity of direct brown dye remained constant after 2 h upto 3 h and for direct brown 2, the adsorption capacity remained constant after 3 h upto 5 h.

The adsorption rate was found to increase quickly in the initial stages. Ho et al. A rapid initial removal of dye was reached within 30 min of contact time and adsorption capacity at equilibrium increased from The rapid removal of dye molecules was due to solute transfer, as there were only adsorbate-adsorbent interactions with almost no interference from solute-solute interactions by Kaczmarski and Bellot The initial rate of removal was therefore greater for high initial methylene blue dye concentrations, the resistance to the dye removal losing as the mass transfer driving force increased.

The significant removal of dyes was observed in the first 20 min and equilibrium condition was reached in min. However, for the sake of combined experiments, an equilibrium time of 90 min was measured to be optimum in further experiments. Effect of particle size: The fact that there exists a direct relation between the surface area of adsorbent and its adsorption capacity makes particle size of adsorbent a very important parameter. The relation between particle size and the percent removal of direct dyes was studied by Gong et al.

They examined that adsorption capacity of the adsorbent increased with decrease in particle size. The effect of different sizes of the adsorbent particles on the removal of Congo red dye was analyzed by Jain and Sikarwar They found that adsorption increased with the decrease in adsorbent particle size for both activated carbon and sawdust biomass. The maximum adsorption This may be attributed to the increased surface area offered by the smallest particle size of adsorbent. The percentage removal at equilibrium decreased with increase in particle size and increased with increasing adsorbent dosage.

With smaller adsorbent particle the rate of adsorption is relatively higher and this is because smaller particles offer larger surface areas and more adsorption sites or in other words surface to mass ratio increases. Sutar and Ranade also found an inverse relation between particle size of adsorbent and rate of adsorption. The removal percentage of As size Disperse blue DB and disperse orange 25 DO dyes, having an azo group are toxic when they enter the environment in a quantity or concentration that has direct or enduring harmful effect on the environment as well as aquatic ecosystem.

These dyes are also used for sublimation printing of synthetic fibers and are the colorant used in crayons, inks and commercially sold as "Iron-on transfers". Mostly, mixture of different dyes is used for final color of textile Many dyes often contain not only the main component, but also several impurities Colored substances present in aquatic living organisms have been associated with changes in protozoan colonization rate, phytoplankton species composition and primary productivity.

In addition, secondary production, macro-invertebrate behavior and macro-invertebrate community system can also be affected. Ions of disperse dyes in the water streams either reflect back the solar radiation or scatter in the water bodies. The entire ecological cycle including self-purification system of water stream is disturbed due to lack of dissolved oxygen. Dye is also associated with other organic toxins such as wood extracts and chlorinated organic substances formed during the bleaching stages.

The specific surface area can be calculated using BET method having saturated pressure mmHg. High surface area of adsorbents has the structures of small particle sizes, with medium surface areas and whose mesopores are the principal contribution to their porosity. Overall, for more adsorption occurs on the surface of adsorbent, the surface to mass ratio should be more, which provided more site of adsorption of pollutants.

A good adsorbent should generally possess a porous structure resulting in high surface area and the time taken for adsorption equilibrium to be established should be as small as possible so that it can be used to remove dye wastes in lesser time. Presently wastewater treatment is emerging field for research due to increasing rate of population with respect to limited resources. Water pollution is heavily generated by anthropogenic activity including industrial discharge which are unable to treat the colored wastewater coming out from various process outlets due to high cost of treatment.

Wastewater treatment and reuse is necessarily in regards to water balances and management. In this study, we attempted to summarized the use various adsorbents, abundantly available and modified precursors for adsorption of disperse dyes from aqueous solution. It is great challenges to treat textile wastewater, especially when the wastewater have more than one component and study of the possible interactions between different chromophores is very useful for the treatment of real effluents.

During the investigation, decolorizing efficiencies based on various essential factors like pH, agitation speed, adsorbent dose, adsorbate concentration, temperature, contact time were noted. Due to the anticipated water scarcity, the concern must be taken up on priority for wastewater treatment. An effort has been made to review the efficiency of various adsorption techniques used for dye removal from colored wastewater and the use of economical techniques for successful wastewater treatment and management.

The first author is highly grateful to Mr. Ramesh Pandey and Ms. Vibhuti Mishra for supporting this study. Subscribe Today. Science Alert. All Rights Reserved. Review Article. Markandeya , S. Shukla and D. Similar Articles in this Journal. Search in Google Scholar. How to cite this article: Markandeya , S. Mohan, Research Journal of Environmental Toxicology, DOI: Table Aad, G. Abajyan, B. Abbott, J. Abdallah and S. Abdel Khalek et al. B, Zablouk and A. Abid-Alameer, Experimental study of dye removal from industrial wastewater by membrane technologies of reverse osmosis and nanofiltration.

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Hameed and N. Aziz, Adsorption of direct dye on palm ash: Kinetic and equilibrium modeling. Bhanger, S.

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Iqbal and S. Hasany, Sorption potential of rice husk for the removal of 2,4-dichlorophenol from aqueous solutions: kinetic and thermodynamic investigations. Mater, Isoglu, Alshirifi, Effect of different parameters on the adsorption of textile dye maxilon blue GRL from aqueous solution by using white marble. Asian J. ElSayed, A. Baraka and M. Abdelmaged, Factors affecting the removal of a basic and an azo dye from artificial solutions by adsorption using activated carbon. A: Chem. Demirbas, S. Celikcapa and M. Dogan, Sorption of acid red 57 from aqueous solution onto sepiolite.

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