Basic Dyes Research Articles

Synthesis of boron carbon nitride layers for the adsorption of hazardous basic dye from aqueous solutions

Synthesis of boron carbon nitride layers for the adsorption of hazardous basic dye from aqueous solutions

Application of polyurethane foam/zinc oxide nanocomposite for antibacterial activity, detection, and removal of basic dyes from wastewater

In this paper, a new multifunctional nanocomposite was synthesized to combine both the advantages of sorption properties and antibacterial efficiency. The thiourea polyurethane/zinc oxide nanocomposite was prepared by coupling thiourea polyurethane foam and zinc oxide nanoparticles. The thiourea polyurethane/zinc oxide was characterized using several tools. The change in the surface chemistry of the thiourea polyurethane/zinc oxide nanocomposite (surface area was increased from 2.8 to 10.6 m2/g), due to the attached functional groups, increased its sorption properties. Also, the thiourea polyurethane/zinc oxide showed a crystalline phase, embedded inside the amorphous structure, with good thermal stability to 230 °C. The pore volume and radius of thiourea polyurethane/zinc oxide were 0.017 cm3/g and 3.4 nm with mesopores/micropores ratio of 11:1. It combines collecting pollutants on its surface, the ability to degrade these pollutants, and a good antibacterial effect. Thiourea polyurethane/zinc oxide was applied for the removing toluidine blue and brilliant green basic dyes from the wastewater. Several parameters such as pH, dye concentration, temperature, and time were studied. The removal percentages of brilliant green and toluidine blue dyes from the wastewater were 92.4–98.2% at pH 3–12. Also, the removing rate of the dyes was very fast (3–5 min) at 25 °C. The estimated capacities of new nanocomposite for toluidine blue and brilliant green were 92 and 227 mg/g. The removal process was spontaneous (ΔG was − 7.3 and − 8.6). As a result, the applicability of thiourea polyurethane/zinc oxide as an effective renewable antibacterial sorbent for removing cationic dyes was maintained.

A Study on Dye Inclusion Complex, Adsorption, and Kinetic of Silk Floss Sheet Modified with β‐Cyclodextrin as a Biodegradable Adsorbent

AbstractIn this study, the silk floss sheet (SFS) modified with β‐cyclodextrin (β‐CD) is used to adsorb various dyes (anionic: Acid Red 33/ AR33, cationic: Basic Blue 9/ BB9, and non‐ionic: Disperse Yellow 26/ DY26) from colored solutions. The various analyses (fourier transform infrared spectroscopy (FTIR), X‐ray diffraction (XRD), ultraviolet‐visible spectroscopy (UV‐Vis), and elemental analysis) are used to study the inclusion complex between β‐CD and the mentioned dyes. In addition, the influence of experimental parameters on the adsorption process (such as dye molecular size, adsorbent dosage, initial dye concentration, contact time, and pH) is assessed. The results show that the molecular size and pH have more effect on the adsorption capacity of SFS. It is found that optimum adsorption of acid and disperse dyes occurrs at pH 4, while basic dye can adsorb at around pH 10. Also, the experimental data have a good fit with the Langmuir equation and the kinetic data can correlate with the second‐order equations. Finally, the desorption studies show that this natural adsorbent can be reused many times without any change in its adsorption capacity.

Green synthesis of magnetic iron-coated mint leaves based carbon adsorbent for acid and basic dye adsorption

In this study, magnetic iron-coated mint leaves based carbon adsorbent (MMC) was synthesized by the green synthesis method and the characterization of MMC was determined by SEM-EDX, FTIR and Raman analyses. In the study, to determine the adsorption capacities of MMC adsorbent for acid blue 193 and basic violet 7 dyes, studies were carried out at different pH, adsorbent dose, dye concentration and adsorption times, and the conditions for the best dye removal were determined. The highest acid blue 193 dye removal was achieved to 79.8% at pH 2 and 10 g/L MMC and the highest basic violet 7 dye removal was obtained as 98.6% at 5 g/L MMC and pH 11 using MMC adsorbent. The adsorption of dyes with MMC was by the pseudo second order kinetics and was more suitable for the Langmuir isotherm. In the adsorption of acid blue 193 and basic violet 7, the qmax values with Langmuir isotherm were calculated as 15.55 and 27.55 mg/g, respectively. As a result, it has been thought that this MMC adsorbent, which is synthesized as a low-cost and environmentally friendly adsorbent, can be efficient in the acid and basic dyes removal from wastewater.

Functionalized magnetic biocomposite based on peanut husk for the efficient sequestration of basic dyes in single and binary systems: Adsorption mechanism and antibacterial study

In this study, an efficient and highly recyclable magnetic biocomposite based on peanut husk (labeled as MPN-Cit) was synthesized for the adsorption of Methylene Blue (MB) and Rhodamine B (RhB) dyes in single and binary systems. MPN-Cit was found to be a crystalline magnetic adsorbent with mesoporous structure and acidic functional groups based on the results obtained from the characterization studies carried out. Adsorption study via the batch method showed that the maximum monolayer adsorption capacity of MPN-Cit for MB and RhB was 245 and 57.3 mg g−1 at 303 K, respectively. The chemisorption process dominated the uptake of MB onto MPN-Cit whereas the physisorption process largely dominated by the hydrogen bonding was the major mechanism underlying the uptake of RhB. MPN-Cit in the binary system exhibited greater affinity towards MB as compared with RhB in all of the competitive systems and in actual wastewater. Another significant feature of this study is the ability of the loaded adsorbents (i.e. MPN-Cit-MB and MPN-Cit-RhB) to exhibit antibacterial properties; which our search shows has not been fully investigated. These results coupled with the high recyclability of MPN-Cit for further adsorption cycles and its ease of separation enhance its practical prospects.

Conventional and molecular identification of Brucella isolates from livestock in Turkey

The main object of the study is to demonstrate that Bruce-ladder multiplex PCR, which is capable of identify all Brucella species including vaccinal strains, is a safe and practical method that is alternative to bacteriological culture methods. Brucellosis is a zoonosis of great socio-economic importance which is endemic in Turkey. In three-year period from 2009 to 2011, a total of 281 Brucella spp. isolates from cattle, sheep and goats were identified and characterized by both conventional biotyping procedures and the PCR based method called Bruce-ladder. Species identification from both phenotypic testing and Bruce-ladder was concordant for all isolates tested. The results showed preferred host pattern in B.abortus isolates. In terms of species identity, it was found that 94% of the isolations derived from cattle were B.abortus and were exclusively biotype 3. B.melitensis biotype 3 and biotype 1 were the prevelant biotypes in sheep and goats. Two isolates from sheep were identified as B.melitensis Rev.1 vaccine strain. Surprisingly, one of the goat isolates was identified as B.abortus S19 vaccine strain. Other interesting observations were the isolation of penicilin-sensitive non vaccine strains of B.abortus and B.melitensis as well as an isolation of an atypical B.abortus biotype 3 strain on the basis of growth inhibition in the presence of basic fuchsin dye. At the end of this study, it was concluded that monitoring Brucella isolates and identify them are indispensable epidemiological tool for brucellosis control

Removal of a basic textile dye by releases of djebel onk phosphates

Removal of a basic textile dye by releases of djebel onk phosphates

EVALUATION OF MARGINAL ADAPTATION AND MICROLEAKAGE OF DIFFERANT ALL-CERAMIC PORCELAIN SYSTEMS

ABSTRACT Purpose: This study evaluated the marginal adaptation and microleakage of the İn-Ceram Alumina, In-Ceram Zirconia and Finesse press all-ceramic porcelain systems. Material and methods: Thirty maxillary Central teeth extracted for periodontal reasons without caries and cracks were divided equally into three group and there was no control group; only the three systems were compared. Sample teeth cemented were stored in distile water for 24 hours. Then, they were applied to a repeated thermal cycle for 500 times. The samples were left in %5 of basic fuchsin dye for 24 hours. For the marginal adaptation rankings, all of the sample teeth for which cross-sections were made were moved into the metal microscope (Scherr Turico St. James/ Minn./ USA) and the marginal adaptation degrees were measured in both the palatinal and vestibul regions by measuring twice with x10 enlargement at micron level. For the statistical evaluations of marginal adaptation and microleakage values, Kruskal Wallis test has been used (p>0.05). Results: The differences between the three all-ceramic porcelain systems are not significant (p>0.05), α=0.05). Conclusion: The Finesse porcelain system caused the least leakage in both regions. In second place in both regions was In-Ceram Alumina, In-Ceram Zirconia caused the most leakage in both regions. The biggest margin gap in the palatal region was seen in the Finesse porcelain system, In-Ceram Zirconia in second place. The least marginal gap was caused by the In- Ceram Alumina porcelain system.

Removal of methylene blue (basic dye) by coagulation-flocculation with biomaterials (bentonite and Opuntia ficus indica)

The use of conventional chemical coagulants and flocculants to treat pollutant-laden effluents generates residues with harmful effects on the environment. This has led us to think through this study of their replacement by more ecological natural products. The present work focuses on the use of a bentonite-based coagulant and a cactus-based flocculant (Opuntia ficus indica (OFIP)) in the elimination of a methylene blue (MB), a basic textile dye. The biomaterials are characterized by FTIR, XRD, SEM and pHPZC. To estimate the performance of the biomaterials in the coagulation-flocculation process, jar-test work was performed on the MB dye in aqueous solution. The monitoring of the variation of MB removal rates was performed by UV–visible spectroscopy. The effect of biomaterial masses, stirring time and speed and settling time on the dye removal process were studied. In addition, the effects of pH and initial MB concentration were also studied. The results show that a mass of 0.9 g of bentonite and 0.4 g of OFIP are the optimal quantities, giving a dye removal rate of 98.29 % during 19 min, at a stirring speed of 180 rpm and 40 rpm for coagulation and flocculation, respectively. These optimum values are obtained with a settling time of 15 min. However, pH does not have a significant influence on the MB removal rates. These biomaterials gave excellent results with 98.99 % dye removal rates at an initial MB concentration of 90 mg/L. In addition, for the purpose of testing the performance of the biomaterials, a comparative study using conventional chemicals was performed.

Comparative analysis of aged documents by desorption electrospray ionization-Mass spectrometry (DESI-MS) imaging.

Document dating is an important and challenging task in the field of forensic science. With the development of analytical techniques, related methods are emerging for document dating studies. Desorption electrospray ionization-mass spectrometry (DESI-MS) is an ambient ionization-MS technique that has been applied in the forensic discrimination of inks. This study focused on utilizing DESI-MS to distinguish between ink entries of different ages. Blue ballpoint ink and black gel ink samples were artificially aged by heat and light exposure and then screened by DESI-MS in the positive ion mode, with a methanol-water-formic acid solution (90:10:0.1%, v/v/v) as the desorption solvent. As a result, the artificially aged ink samples were directly differentiated from the reference ones in the chemical images of age-dependent compounds such as basic dyes or polyethylene glycol derivatives. The amount of ethoxylated fatty amine surfactants in copy paper was also found to decrease after artificial aging. Moreover, this method enabled us to visualize the differences between the composition of naturally aged and fresh ink samples. It has been proven to cause no apparent destruction of the samples. The identification of chronological changes in document materials suggests that the DESI-MS method is a promising approach for relative document dating.

Development of adsorbent rigid structure based on Spirulina sp./chitosan bioblends coatings for dye adsorption in fixed bed column.

The glass particles were coated with Spirulina sp. LEB-18 and bioblends of Spirulina sp. LEB-18/chitosan by casting technique and, afterward, it was verified its potential as adsorbents for basic and acid dyes. Nine Spirulina sp. suspensions with different components were used to coat the glass particles, and in the best condition of coating were prepared the bioblends with chitosan. The coated glass particles with Spirulina sp. and its bioblends with chitosan were applied in adsorption of the allura red (acid) and methylene blue (basic) dyes in a batch operation evaluate the pH effect, and a fixed bed column operation, being evaluated to the removal percentage and adsorption capacity of the column. The glass particles coated with Spirulina sp. applied in batch adsorption showed the highest removal percentages for allura red dye (35 to 45%) at pH 4.0, and for methylene blue dye (35 to 80%) at pH 6.0 and 8.0. In fixed bed column using glass particles coated with bioblends were reached the amount dye of 54.2mg of adsorbed allura red dye and 60.2mg of the of adsorbed methylene blue dye, respectively. Moreover, it was found good dye adsorption capacities, around 89mgg-1, for both dyes, in acidic and basic pH values. Based on these results, these bioblends coated glass particles can be applied as an adsorbent for different types of dyes in adsorption column.

Efficient use of agricultural wastes as Biosorbent in the removal of Fuchsin basic dye from aqueous solutions

Batch mode adsorption studies of Fuchsin basic (FB) on different agricultural waste materials were carried out using parameters including initial FB concentration, adsorbent dosage, agitation time, particle size of adsorbent and temperature. The best fitting isotherm model is elucidated using linear regression coefficient (R2). Both Langmuir (R2?0.998) and Freundlich (R2 = 0.968 to 0.986) isotherms were found to be best fitting model for the adsorption studies. The monolayer (maximum) adsorption capacities were found to be between 142.857 to 250 mg/g of given adsorbents. Lagergren pseudo -second order model best fits the kinetics of adsorption as qe(the) values are in consistent with qe(exp) with whole range of agitation time. Adsorption process was found to be directly proportional to temperature but inversely proportional to particle size of adsorbent. Thermodynamic analysis showed that adsorption was favourable, spontaneous, increased disorder and randomness at the solid- solution interface of FB with adsorbents. Mangrove plant leaf powder was found to have greater adsorption capacity towards FB amongst the adsorbents under study.

Rendering Viscose Fabrics Dye-able with Basic and Acid Dyes Using Citric Acid and Chitosan Nano Particles Based Finishing Formulation

ABSTRACT The innovation anticipated here is the use of our previously prepared chitosan nanoparticles in conjunction with citric acid and sodium hypophosphite for rendering viscose fabrics dyed and finished concurrently in one step with dual classes of dyes, namely basic and acid dyes, using a pad-dry-cure process. This was done to see the effect of the aforementioned eco-friendly finishing formulation on creating dual anchoring sites onto finished fabrics for dye-ability using Basic Red 2 and Acid Orange 7, which have no direct affinity to viscose fabric. So, different concentrations of CA, CNPs, and dyes were mixed into a viscose fabric cross-linking formulation together with a set concentration of SHP (50% based on weight of CA concentration) and cured at 170°C for 2 minutes. Citric acid is predicted to react with the hydroxyl groups in viscose and CNPs to produce ester crosslinking and/or to form an inter-ionic attraction with the amino groups of CNPs. The latter was responsible for viscose fabrics dye ability with Basic Red 2 by anchoring the free carboxyl groups in citric acid, as well as their dye ability with Acid Orange 7 by anchoring the residual amine groups in CNPs.

Sorption of BB41 dye molecules using chitosan based particles from aqueous solutions: A kinetic and thermodynamic evaluation

In this study, starting from chitosan is a hydrophilic polymer with positively charged, it was aimed to produce chitosan-based particles and to be evaluated as a sorbent. Chitosan-based polymeric particles production was carried out by the precipitation-collection method from chitosan. Chitosan and chitosan-based sorbent were characterized. For this purpose, SEM and FTIR analyzes were used. Sorption activities of the chitosan-based polymeric particles were investigated for basic dye (basic blue 41, BB41). The effect of various sorption parameters (temperature, initial pH value, chitosan amount, initial dye concentration, contact time, etc.) on the sorption efficiency of BB41 dye molecules was investigated. The optimum sorption conditions were determined. The optimum temperature of solution, initial pH value, chitosan amount, contact time and initial BB41 dye concentration were determined as 25 °C, 10.5 ± 0.02, 1 g/L, 240 min and 50 ppm, respectively. Sorption capacities at 25, 35, 45, and 55 ℃ were determined as 1.710, 1.410, 1.360, and 1.200 mg/g, respectively. In addition, the sorption yields were determined as 85.00%, 73.21%, 67.86%, and 60.00%, respectively. Experimental results were evaluated by applying Langmuir, Freundlich, Temkin, and Dubinin-Radushkevich's (DR) isotherm models. It was determined that the obtained data fit well with the Langmuir isotherm model. The maximum sorption capacity (qmax) was calculated to be 1.920 mg/g. To calculate kinetic parameters, pseudo-first-order, pseudo-second-order, Elovich, and intraparticle diffusion kinetic model equations were used in the study. It was determined that the pseudo-second-order model was better suited to explain the experimental data. Using the pseudo-second-order kinetic model equation, the maximum sorption capacities (qc,h) for 25, 35, 45, and 55 °C were calculated to be 1.720, 1.490, 1.380, and 1.240 mg/g, respectively. It was determined that the desorption activities of chitosan particles were over 99.5%. The chitosan particles retained their physical stability under the specified desorption conditions. It was decided that it was a suitable sorbent for reuse.

Alginate/ZnO beads doped with radiation‐induced silver nanoparticles for catalytic degradation of binary mixture of basic and acidic dyes

AbstractBecause of the increased activities of industrial areas, especially textiles, a huge amount of toxic waste has been accumulated, which badly affects the ecosystem. For decades scientists have tried to find an effective solution for this problem. The main objective of this work was to prepare and characterize easily handled nanocomposite beads composed of alginate/ZnO doped with radiation‐induced Ag nanoparticles to study the competitive degradation of basic and acidic dyes in one mixture to evaluate its degradation ability for divers dyes. Fourier transform infrared spectroscopy, X‐ray diffraction, and transmission electron microscopy studies have helped to characterize nanocomposite hybrid beads with morphological evaluation. The effectiveness of alginate/ZnO/Ag as a catalyst in the degradation of a mixture of basic and acidic dyes was also verified. The main experimental factors such as time, the initial concentration of binary dye mix, and the amount of catalyst were studied to determine the best degradation conditions. The results show that a high percentage of degradation of the dye mixture occurred within 75 min. The amount of ALG/ZnO/Ag beads was optimized as 0.5 g for complete degradation of the dye mixture at concentration of 100 mg/L. The study's results demonstrate that the ALG/ZnO/Ag hybrid nanocomposite catalyst has great ability for the catalytic degradation of a binary mixture of basic and acidic dyes where increasing the amount of catalyst increased the degradation to 95% for basic dye and 85% for acidic dye. In addition, monitoring the degradation process showed that the degradation percentage of basic dye was higher than that of acidic dye in the same mixture.

Synthesis and Structural, Optical and Photocatalytic Properties of Erbium doped Silica Nanocomposites

Nowadays, increasing population and advanced industrialization have extended the use of synthetic dyes in day-to-day life which further results in dye pollution. Large numbers of photocatalysts are being used in industry to reduce pollution. In the present study, the Erbium doped silica nanocomposites were synthesised by sol gel method and used for photocatalytic applications. The characterization of catalysts was carried out by Powder X-ray diffraction analysis (XRD), Flame Emission scanning electron microscopy (FESEM), Energy-dispersed X-ray analysis (EDX), High Resolution transmission electron microscopy (HR-TEM), Ultra Violet Spectroscopy (UV) and Fourier Transform Infra-Red Spectroscopy (FTIR). The photocatalytic response of nanocomposites was evaluated for different synthetic dyes. Acidic dyes like methyl orange, methyl red, congo red and basic dyes such as methylene blue, rhodamine B and crystal violet were studied in aqueous solution under visible light irradiation. The composite showed enhanced photocatalytic activity for these synthetic dyes.

Comparative Evaluation of the Adsorption Performance of Citric Acid-Treated Peels of Trapa natans and Citrullus lanatus for Cationic Dyes Degradation from Water

Various chemicals were explored in chemical combinations with two selected agrowastes in order to optimize, enhance, and improve their biosorption potential for the optimal and effective eradication of noxious, carcinogenic, and malignant cationic and basic dyes from wastewater. In this project, environmentally safe, economic, inexpensive, and widely available peels of Trapa natans (TP) and Citrullus lanatus (CP) were collected, dried, and pretreated with citric acid, revealing promising results. FT-IR and SEM characterizations of chemically changed biosorbents (C-TP and C-CP) have evidenced the presence of more secondary adsorption sites on their surfaces. These acid-modified biosorbents were employed to eliminate the hazardous and toxic basic dyes such as Rhodamine B (RAD) and Brilliant Green Dye (BLG) in batch mode processing. The Langmuir model was best fitted to equilibrium experimental data as compared to Freundlich and Temkin isothermal mathematical models with Qmax of 15.63 and 27.55 mg/g for RAD using C-TP and C-CP, respectively, whereas, for BLG on C-TP and C-CP, it was 128 and 189 mg/g, respectively. Therefore, the mechanism is related to chelation and ion exchange modes between adsorbate molecules and adsorbent surfaces, leading to homogeneous and monolayer adsorption and following pseudo-2nd-order kinetics in the best way. Thermodynamic parameters such as ΔG0, ΔS0, ΔH0, and ΔE0 are determined statistically for the adsorption performance of both novel chemically mutant biosorbents, which reflect that biosorption mechanisms are exothermic as well as spontaneous.

Megaporous monolithic adsorbents for bioproduct recovery as prepared on the basis of nonwoven fabrics.

Megaporous adsorbents were prepared based on nonwoven polyethylene terephthalate (PET) fabrics and functionalized by covalent modification with polyvinylamine (PVAm) or monotriazinyl-β-cyclodextrin-substituted polyvinylamine (PVAm-MCT-β-CD). Mechanical properties of the resulting fabrics were maintained, as judged by tensile strength tests and scanning electron microscopy. Exceptional porosity (≥82%) and preserved hydrodynamic characteristics (Pe≥63) indicated excellent structural stability when packed. The performance of the constructed adsorbents was evaluated with high molecular weight (proteins) and low molecular weight (dyes) model compounds. The static binding capacity (SBC) for bovine serum albumin (BSA) was 79.7±1.3 and 92.9±8.2mg/g for PVAm-modified and PVAm-MCT-β-CD-modified fabrics, respectively. The mentioned materials also adsorbed Orange II, an acidic dye (92.4±2.6 and 101.9±2.6mg/g, respectively), indicating that the hydrophobicity was a prevailing binding mechanism operating at a pH close to isoelectric point. SBC for lysozyme and toluidine blue O (TBO, a basic dye) onto PVAm-MCT-β-CD functionalized PET was 52.7±5.1 and 73.3±0.6mg/g, respectively. TBOs have also shown some affinity for PVAm functionalized PET, but this was most likely to be mediated by hydrophobicity. On the other hand, operating at a superficial velocity of 90cm/h, dynamic binding capacity for BSA was 11.4±3.5 and 2.5±0.6mg/g indicating the importance of possible aggregation mechanisms during protein binding at equilibrium. Thus, PET-based adsorbents require further functional improvement for chromatography applications. However, the easy-to-construct, scalable nonwoven adsorbents deserve further attention as a potential alternative to packed-bed-chromatography adsorbents.

Removal of color and COD from textile dyeing effluent by adsorption technique using montmorillonite clay

AbstractThe study involves the removal of color and COD from textile dyeing effluents using the method of adsorption. Montmorillonite clay is used as an adsorbent. The surface area of the adsorbent is increased using acid treatment techniques with Para Toluene Sulfonic Acid (PTSA) and Phenol Di‐Sulfonic Acid (PDSA) solutions. In addition, the dosage of adsorbent for maximum removal of color and COD, the effect of contact time on adsorption, and the treatment cost of montmorillonite clay with PTSA and PDSA were determined. From the results, the surface area of montmorillonite clay increased from 30 to 119 m2/g and 246 m2/g upon treating it with PTSA and PDSA solutions, respectively. Raw montmorillonite clay was able to adsorb 89% of acid dye with a dosage of 1.8 g/100 ml and 93% of basic dye with a dosage of 1.0 g/100 ml for a dye having an initial concentration of 2000 mg/L. With an increase in the surface area of modified montmorillonite clay, it was able to adsorb about 95% of acid dye with a dosage of 1.2 g/100 ml and 96% of basic dye with a dosage of 0.5 g/100 ml. Concerning Acid Blue1 dye, about 86%, 90%, and 93% of the dye were adsorbed in the initial 2 min for raw montmorillonite clay, modified montmorillonite clay treated with PTSA, and PDSA solution, respectively. In the case of Basic Yellow2 dye, about 86% of the dye was adsorbed in the initial 2 min for raw montmorillonite clay and the clay treated with PTSA solution, whereas about 96% of the dye was adsorbed onto clay treated with PDSA. Regarding Basic Violet1, about 98%, 96%, and 99% of the dye were adsorbed in the initial 2 min for raw montmorillonite clay, clay treated with PTSA, and clay treated with PDSA solution, respectively. The cost of treatment of clay with PTSA and PDSA solutions is found to be Rs. 1.70/g or 0.023 $ per gram and Rs. 6.6/g or 0.089 $ per gram of clay, respectively. Therefore, considering the cost of treatment, clay treated with PTSA is preferred over clay treated with PDSA solution.

Biosorption Study of Methylene Blue (MB) and Brilliant Red Remazol (BRR) by Coconut Dregs

Water pollution has become a major issue in many countries, including Malaysia. Malaysia is one of the countries that suffers from this detrimental influence on water resource sustainability. Adsorption has been discovered to be a cost-effective and efficient method of removing contaminants such as pigments, dyes, and metal impurities. Many biomass-based adsorbent materials have been successfully used for the removal of dyes from aqueous solutions. In this study, the potential use of coconut dregs as the new biosorbent for the removal of Methylene Blue (MB) (basic dye) and Brilliant Red Remazol (BRR) (acidic dye) was investigated. The effects of adsorption time, adsorbent dosage, pH, and initial dye concentration on coconut dregs adsorption for MB and BRR dye were investigated using 2-Level Factorial Design of Design-Expert 7.1.5. The results indicated that the amount of dye adsorbed on the coconut dregs increased with increasing dye concentration, adsorbent dosage, and adsorption time. However, both MB and BRR dyes favor different pH for the adsorption process. The adsorption capacity of MB dye increased with increasing pH, while the adsorption capacity of BRR dye increased with decreasing pH. Removal of MB was optimum at pH 11, contact time of 240 min, a dosage of 0.25 g adsorbent, and an initial dye concentration of 50 mg/L. Meanwhile, for BRR dye, the optimum condition was pH 2, contact time of 180 min, the dosage of 0.25 g adsorbent, and an initial dye concentration of 50 mg/L. The equilibrium data for both dyes fitted very well with the Langmuir Isotherm equation giving a maximum monolayer adsorption capacity as high as 5.7208 mg/g and 3.7636 mg/g for Methylene Blue Dye and Brilliant Red Remazol dye, respectively. This study shows that coconut dregs can be one of the potential and low-cost biosorbents for the treatment of industrial dyes soon.