1 Introduction

Water is paramount and important for the sustainable development of healthy life throughout the world [1,2,3,4,5,6]. However, water pollution with numerous industrial noxious elements is recently considered as the greatest stimulating substances throughout the world, particularly in developing countries like Ethiopia [7, 8]. Now a day, the presence of various contaminants including toxic inorganic nutrients, different organic species, and fuel related products have been reported throughout the world in aquatic systems [8, 9]. As a result of their noxiousness and bioaccumulation, the stated above pollutants pose prodigious hazards for individuals and other environments [10,11,12,13]. The increasing of widespread pressure on industry is due to the increase in world population and expansion. Particularly, requirements on textile industries to meet the human requests for industry have been facing a challenge in many countries [1,2,3, 14]. These industrial processes put away great amounts of water and yield enormous quantities of wastewater that are full of organic and inorganic chemicals such as dyes [15, 16]. Currently, for one kilogram of fabric production 95–400 L of water was consumed [2]. Generally, dyes are more soluble and easily discharge effluents to the environment, which makes serious dangers to the environment [7,8,9].

Methylene blue (MB), is a cationic soluble dye in the dissociation reaction in aqueous solutions producing chloride ions and cations. From its application point of view, it encompasses a number of research fields including biomedicine, applied biology, and applied chemistry [17]. In general, the definition of MB (3,7-bis(Dimethylamino)-phenothiazin-5-iumchloride) dye is a thiazine soluble cationic dye that is broadly used to dye textiles, such as cotton, cellulose, wood, and silk [2]. Besides the significance of MB dye in these disciplines, it has toxic effects on human beings and the surroundings in arrears of MB’s solubility nature from top to bottom in aqueous system. These dyes can cause cancer, skin irritation, allergic dermatitis, and mutations [18]. Because of this, eliminating cationic MB dye from wastewater before its harm has become very essential aspect. For an increased period of time, several methods are situated for the elimination of toxic pollutants including adsorption, coagulation, precipitation, filtration, solvent extraction, reverse osmosis, and ion exchange [19,20,21,22,23,24,25,26,27].

No matter how, most of the above stated methods require high cost, with relatively low eradication capacities and require extra price for remediation [28], amongst these methods, adsorption appears to be the most alternative owing to its less price, greatest economic output, eradication of contaminants with very decreased level, greatest uptake capacity as well as obtainability of widespread variety of sorbent resources including carbon activated material, nanotubes of carbon based material, as well as Nano composites [29]. Due to the low price and easily reusing of adsorbent resources, natural-based resources (resources from cellulose, resources from chitin, resources from chitosan, resources from gelatine, and resources from others) are the current choosen for the elimination of noxious dyes from water.

From these polymeric materials, cellulose takes the enhanced merits of comparative, simply obtainable, not toxic, as well as reach in hydroxyl functional groups accessible for different chemical amendment reactions [18]. Despite their marked features, the disadvantages of cellulose based materials in contaminated water cleaning is that it takes delayed hydrophilicity, less physical and chemical stability, and limited pollutants uptake competence [29]. Due to this reason now a day, the synthesis of nanomaterials for adsorbing adsorbates are growing [30]. No matter how, nanomaterials, including titania doped nanocomposite nanotubes of carbon-based materials, as well as iron nanomaterials with zero oxidation number are termed as noxious and improper to pollutant elimination [30]. The drawbacks stated above can be situated simply resolved synthesizing adsorbent materials by disintegrating cellulose materials into cellulose nanoparticles (CNPs) using different preparation methods [31]. Regarding to its synthesis methods and origin materials, nanocellulose could be categorized into cellulose nano-fibers (CNFs), cellulose nanocrystals (CNCs), and bacterialcellulose (BC) [26]. In this study, cellulose nanocrystal (CNC) was prepared due to the preparation method used here in sulphuric acid hydrolysis.

A number of investigations were performed previously using nano-cellulose resourced adsorbent materials prepared using diverse natural-based resources such as date palm (Phoenix dactylifera L.) [32], residues from cotton [33], banana linter [34], husk obtained from corn [35], and others. As per knowledge of the researcher, few works were reported using cellulose nanomaterials (CNMs) prepared from the fibers of cotton collected from Adama region, Zekala market. The reason for the selection of cotton fiber than others was due to the presence abundance cellulose content in cotton than other polymeric materials [33]. Additionally, for improvement of CNPs surface area chemical amendment of CNPs surface was done by using different oxidizers, such as perchlorate, perbromate sodium periodate, etc. chemicals. Among these, sodium periodate was selected due to it has an exceptional reactivity and selectivity in the direction of 1,2-diols, whereas presenting a greater acceptance for many common functional groups at appropriate solution pH and temperature. Furthermore, its reduction is kinetically favored in comparison to perchlorate and perbromate [36]. In addition to this, to the greatest of the researcher knowledge, most of the researches carried out in the reported references were using aqueous solution merely, but there is a research gap on real wastewater treatment. Therefore, this study aims at looking CNP prepared from the fibers of cotton collected from Adama region, Zekala market for the elimination of cationic MB dye found in textile SERWW.

2 Equipment’s and techniques

2.1 Different chemicals

The analytical grade chemicals were purchased and used for the experiments. They were namely, NaClO2 (80%, Shanghai ZZ New Material Tech. Co., Ltd., China), CH3CH2OH (97%, Tradewell International Pvt. Ltd, India), toluene (99%, Loba Chemie Pvt. Ltd, India), NaOH (99%, Shraddha Associates (GUJ) Pvt. Ltd., India), conc. HCl (35%, Loba Chemie Pvt. Ltd., India), conc. H2SO4 (69%, Loba Chemie Pvt. Ltd., India), conc. HNO3 (69%, Loba Chemie Pvt. Ltd., India), Methylene Blue trihydrate (MB) (C16H18ClN3S⋅3H2O, Consolidated Chemical and Solvents LLC, USA) and sodium bicarbonate (99%, Shraddha Associates (GUJ) Pvt. Ltd., India).

2.2 Sample collection and cellulose nanomaterial preparation

The fiber of cotton for cellulose nanoparticle fabrication was collected from Adama region, Zekala market, Ethiopia. Next, the textile secondary runoff industrial wastewater (SERWW) was acquired from Addis Ababa, Ethiopia. After this, the collected fiber of cotton sample was cleaned by deionized water many times as well as it was dried out with the help of air at 25 °C and grinded with a clean mill. Then cellulose was fabricated by taking 10 g of carefully dried stem of fiber of cotton plus a combination of 1:1.5 toluene in ethanol solvent for about 46 h at 65 °C followed by cleaning it through heated water and dried out within the oven for 10 h at 50 °C. Then, the fabricated and dried out fibres can be situated and adjusted into roughly 5 mm in length. Followed, the adjusted cellulose, fibers were cured with 90 mL of 2.25 M NaOH solution at 60 °C until 2.5 h and finished for elimination of lignin and hemicellulosis found in the fiber of cotton. This solution was cleaned carefully with deionized water repetitively till to get a solution with pH of 7. Again, the obtained solution with pH of 7 was clarified, separated, and became dry out in the oven at 60 °C for 12 h. At this stage, the solutions became a pulp form through carefully grinding procedure and the bleaching procedure was performed with a 3.5:1.5 combination of sodium chlorite (NaClO2) and glacial acetic acid for 5 h at 70 °C through stirring mechanically. Then, the obtained residue solution was constantly centrifuged, clarified, and dried out to get the suspension of cellulose. The suspension of cellulose was cleaned from lignin, hemicellulose, fluid, etc., due to the carefully treatment of it by 90 mL of 2.25 M NaOH solution. In order to obtain cellulose with free from any non-cellulose components, this trial would be reiterated by one over two of the starting quantity of bleaching reagent. Subsequently, to this solution 90 mL of 6.5 M H2SO4 was added and hydrolyzed until 3 h finished in order to carefully breakdown the cell wall to smaller fibers and to isolate the fibrils from each other. At this stage the white suspension of cellulose nanoparticles (CNP) was rotated at 12,000 rpm to isolate the cellulose nanomaterial and standardized with the help of homogenizer about 12,000 rpm for 3 h. Lastly, the fabricated CNP was stored in appropriate place and taken for characterization of different required techniques. These experimental steps were taken from Kara et al. [18] through slight modification.

2.2.1 Preparation of chemically amended cellulose nanoparticles

For the fabricated CNP surface amendment, 20 g of CNP suspension was taken and reacted with 0.19 L of NaOH solution (19 wt.%) at 25 °C for 17 h through stirring magnetically. After this, the basic CNP obtained was isolated from the mixture solution through a centrifuge and cleaned by deionized water until the solution gets a pH of 7, clarified and dehydrated to dry it. Followed, 10 g of isolated CNP and 20 g of succinic anhydride were reacted in the flask for 18 h. The chemical amended suspension of CNP was stirred and clarified, cleaned by using dimethylformamide (DMF), ethanol, 95%, distilled water, HNO3 (0.01 mol/L), and acetone sequentially. Lastly, the carefully cleaned chemically amended CNP was reacted with a saturated sodium hydrogen carbonate solution for 45 min through a fixed magnetic stirrer and next it was filtered at the end, cleaned with the help of deionized water and then acetone and dried out at room temperature to produce S-CNM. This experimental step was adapted from the study reported by Hokkanen et al. [26] with a minor amendment. Then the chemically amended CNP was stored in suitable place until the end of experimental work. Also, the reaction mechanism of CNP with NaIO4 is given in Fig. 1.

Fig. 1
figure 1

The oxidation reaction mechanism of CNP with NaIO4

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2.2.2 Preparation of synthetic methylene blue stock solution

For 1000 mg L−1 synthetic MB stock solution preparation, a suitable amount of grams of MB was added in a 1000 mL volumetric flask and distilled water was added to this flask. This flask was shaken carefully to dissolve the solutes and distilled water was added up to the mark of the flask. The standard series solutions were prepared from this stock solution through the dilution method. The concentration of MB solution was measured by using UV–VIS spectrometer (SM-spectrophotometer UV–Vis 1600, MaaLab Scientific Equipment Pvt. Ltd, India). The calibration curve was obtained using the maximum absorbance at λmax 664 nm by using MB standard series in the range of 10.0 and 40 mg L−1.

2.3 Characterization

The crystallite size of the NaIO4-CNP adsorbent was analyzed through the help of XRD instrument (Cu-Kα radiation (λ = 0.154 nm) at 40 kV and 40 mA under a 2θ diffraction angle from 0° to 40° at a scan rate of 2°/min). The functional group found on the fabricated NaIO4-CNP adsorbent was recognized through the help of FTIR (Perkin-Elmer, RXI model). The morphology characteristic of the fabricated NaIO4-CNP adsorbent surface was observed through the use of a Hitachi S-4100 scanning electron microscopy (SEM). The precise surface area determination was performed through the use of Brunauer Emmett Teller (BET) analysis. The particle size of the NaIO4-CNP adsorbents was determined using Transmission electron microscope (TEM).

2.4 Adsorption experiments

Firstly, the 1000 ppm stock solutions of MB dye ions were prepared from their soluble salt solutions and the necessary amount of the synthesized and characterized adsorbent (NaIO4-CNP) dose was mixed in a 100 mL flask and stirred with a shaker known as orbital until 60 min. completed. The solution pH of MB solution was justified with the help of non-concentrated NaOH and HCl solutions through the use of a pH meter. By using one separation technique, namely, filtration separates the solid/liquid phases of solution. After this, the absorbance measurement of MB dye was performed by UV–VIS spectrometer (SM-spectrophotometer UV–VIS 1600, MaaLab Scientific Equipment Pvt. Ltd., India) at a λmax of (664 nm). Above all, experiments were performed through measuring of different constituents affecting the cationic MB dye removal capability, including, contact time ranged from 10 to 90 min, solution pH found in the range of 3–12, NaIO4-CNP dose found in the range of 0.4–3.0 g, and initial MB dye ions levels found in the range of 10–40 mg/L. The influences of every one constituent on the MB cation day removal capability were performed through putting the reinto constituents at constant system.

2.4.1 Adsorption isotherms

Isotherms performed for the uptake of MB dye by the adsorbent (NaIO4-CNP) are the most imperative scientific exemplary to explain the appliance of metal ion adsorption on the solid and liquid phases of the sorbent based on a set of imaginations related to the kind of occupancy, how heterogeneous or homogeneous the solid NaIO4-CNP surface and the chance of communication between MB dye. Therefore, the concentration of MB dye eradication by the mechanism known as adsorption was anticipated through the use of a mass balance in the eradication practice. This balance indicates that the quantity of MB dye ions uptake by the NaIO4-CNP adsorbent is proportional to the quantity of MB dye ions that were removed from the textile SERWW. The illustration of the process can be accessible in Eqs. (1) and (2).

$$q_e = \frac{C_i MB - C_e MB}{S}$$
(1)
$$q_t = \frac{C_i MB - C_t MB}{S}$$
(2)

Here, qe and qt characterize the quantity of MB dye cations adhered on the adsorbent (NaIO4-CNP) apparently at optimum (equilibrium) and at the specified period of time (mg g−1), correspondingly. CiMB dye ions and CeMB dye ions signify the initial and equilibrium levels of the MB dye ions in the textile SERWW sample (mg L−1), correspondingly and Ct is the levels of MB dye ions in the textile SERWW sample (mg L−1) at a specific time. S tells the suspension dose giving information as the S-CNP adsorbent mass (g) to the initial volume of water sample (L) ratio. Initially calculated and calculated at equilibrium concentration were ready to describe the MB dye ions percent removal (Eq. 3).

$$\% {\text{R}} = \frac{C_i - C_t }{{C_i }} \times 100$$
(3)

2.4.2 Adsorption kinetics

The rate of the adsorption process is termed as a period of time dependent and is termed the most significant parameter providing valuable data for the velocity of sorption as well as evaluating the NaIO4-CNP eliminating the competences of MB dye ion from textile SERWW. Thus, MB dye ions elimination kinetics progression from textile SERWW was done through the use of the interaction periods of time as 10–90 min. by putting the entire other constituents including pH of the solution, NaIO4-CNP dose, and MB dye ions starting levels at the optimum system.

2.5 Regeneration experiment

The reusability trial of the previously used NaIO4-CNP adsorbent in the adsorption of MB dye cations in the textile SERWW was accomplished through duplicating the trial procedures through the use of similar NaIO4-CNP adsorbent for 4 consecutive rounds. Desorption of MB dye ions was performed through the addition of the optimum NaIO4-CNP CNP value (1 g) previously used as eradicating MB dye cations from textile SERWW to an conical flask with 10.5 mL of 0.1 M HCl solution for 19.5 min and sonication for 60 min. was formed. Afterwards, the material (NaIO4-CNP) was easily alienated from the mixture through the use of centrifugation. The alienated material (NaIO4-CNP) was washed away with the help of distilled water for six times, dried out, and reapplied for four succeeding rounds.

3 Results and discussion

3.1 Characterization

The chemical amended cellulose nanoparticle (CNP) adsorbent was analyzed through the help of FTIR, XRD, SEM, BET, as well as TEM modern instrumental techniques. The powerful tool termed as FTIR spectrometry tells the presence of different functional groups for the fabricated NaIO4-CNP adsorbent as well as its spectra previously and afterwards adsorption is shown in Fig. 2a. The peak shown at 3416 cm−1 previously and afterwards sorption tells the confirmation of cellulose O–H stretching vibration, the peak appears at 2852–2925 cm−1 previously and afterwards sorption showed the occurrence of C–H stretching, the peak appears at 1731 cm−1 before and after adsorption showed the occurrence of C–O stretching vibration of carboxyl groups because of the surface amendment of CNP by succinic anhydride, the peak appears at 1058 cm−1 and 1040 cm−1 previously and afterwards sorption, correspondingly, showed the occurrence of C–O–C stretching of cellulose I [18]. The broad peak and the strident peak previously and afterwards sorption, correspondingly, at 670 cm−1 resemble to ß-glycosidic associations amongst cellulose glucose units. The occurrence of this peak in this study is stimulating; meanwhile it is a suggestion that the acid hydrolysis process may have not been lost the cellulosic material nature. The appearance of the extra peak at 611 cm−1 might be because of the reaction occurring between NaIO4-CNP/metal ions. This is a confirmation of the sorption of MB dye cations on the surface of NaIO4-CNP adsorbent [18]. As a conclusion, NaIO4-CNP adsorbent contains abundantly of carbonyl and hydroxyl functional groups that have large vacant spaces to adsorb MB dye cations by electrostatic reaction made among the negative surface charge of NaIO4-CNP and the positive surface charge of MB dye cations [18].

Fig. 2
figure 2

NaIO4-CNP adsorbent FT-IR spectra (a), NaIO4-CNP adsorbent XRD Spectra (b), NaIO4-CNP adsorbent SEM images (c), NaIO4-CNP adsorbent TEM images (d), and NaIO4-CNP adsorbent EDX spectrum (e), respectively

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Figure 2b shows the X-ray diffractometer spectra of the manufactured cellulose nanoparticles (CNP) to govern the crystallinity size. As it can be seen in the spectral highest peaks at 15.99°, 22.22° and 34.97° specified Cellulose-I structural compounds and resemble the crystals of the representative plane description of 110, 200, and 004, respectively [18]. The size of crystallite was obtained and the value was found 2.45 nm. Likewise, its width of NaIO4-CNP was 3.65 nm. In line with this, Andreas et al. [37] described similar results that entitled on the correlation of nanocrystalline cellulose particle size and its surface area. In general, as seen from the peaks, a semicrystalline with unstructured broadened hemp and crystalline peaks was observed. The finding is owing to the circumstance that the NaIO4-CNP was fabricated from natural-based materials, which could not show 100% crystallinity environment. Additionally, the oxidation process of the cellulose was achieved with the reaction of NaIO4 to form aldehyde cellulose nanoparticle (NaIO4-CNP). The semicrystallinity look as if in the bands possible to the application of sulfuric acid hydrolysis technologies, thus leding a damage of amorphous assembly in the cellulose chain [38].

The spectrum of EDX was given in Fig. 2e revealed carbon, oxygen, chlorine, and sulfur peaks matching to their atomic weights, respectively. The NaIO4-CNP sorbent encompasses 0.83 wt% & 0.08 wt% elemental impurity of sulfur and chlorine sideways with the core constituents such as carbon (52.68%) and oxygen 44.65 as presented in Fig. 2e. The impurity appeared here is may be resulted from the acid hydrolysis of cellulose suspension.

Figure 2c, d indicate the morphology of NaIO4-CNP adsorbent material. As it can be seen, the spectral peak showed the rod-like shape, which exhibited an organized and importantly penetrable cooperated assembly with indelicately even pore size with augmented definite surface area, was detected. This consequently resulted that due to the extremely homogenization of the adsorbent constituents throughout the fabrication development and this meaningfully increased the surface area to volume ratio for NaIO4-CNP adsorbent. Additionally, the fibers of NaIO4-CNP were particularly disconnected from each other. The sodium periodates modification process showed the actual rough surface NaIO4-CNP adsorbent detected by SEM micrographs. As a result, the surface area of NaIO4-CNP augmented through the NaIO4-CNP adsorbent roughness of the surface and reduces the particle size [38, 39]. Therefore, excess vacant sites are exists for MB dye cations adsorption. The morphological feature of NaIO4-CNP was measured by TEM interpretations, and given in the Fig. 2d. The image was shown the nanosized fibril with wide heterogeneous distribution both in width and in length was observed.

Data analysis of BET is able conferring to its linear equation given in Eq. (4) for the description of the NaIO4-CNP adsorbent specific surface area (SSA). This determination was performed at a temperature of 77 K through the use of and adsorbate termed N2 gas.

$$\frac{{{\text{p/p}}_{\text{o}} }}{{n(1 - {\text{p/p}}_{\text{o}} )}} = \frac{C - 1}{{(X_m C)}}({\text{p/p}}_{\text{o}} ) + \frac{1}{X_m C}$$
(4)

In the above Eq. 4, Po and P represent the saturated and partial vapor pressure of N2 gas at steady state value in pa, correspondingly, n represents the N2 gas volume sorbed at STP by using mL as a unit; Xm represents BET monolayer capability; C represents a dimensionless fixed value connected to the enthalpy of N2 gas sorption on the NaIO4-CNP.

Nanoparticles with C value ≥ 80 were considered as a respectable BET monolayer capability [40]. As seen from the findings, NaIO4-CNP adsorbent value for C is 190.6, this indicates the value showed a respectable BET monolayer capability. After this, the linear plots of [(P/Po)/(n(1 − P/Po))] versus P/Po are indicated in Fig. 3a, and make available a straight line with estimated comparative value for pressure presented in the range between 0.05 and 0.3. From the regression result (0.9982), which is greater than 0.995 indicated that the confirmation of the satisfactory level of regression value. Based on Eq. (5), the SSA of m2·g–1 value is obtained.

$$a_s = \frac{X_m L\sigma_m }{{mx22400}}$$
(5)
Fig. 3
figure 3

The NaIO4-CNP linear plot (a) and the NaIO4-CNP BET plot (b)

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In the above equation, 5 L equal to value of 6.022 × 1023 mol−1, as represents the NaIO4-CNM adsorbent specific surface area of the of mass m in grams for BET analysis, σm represents N2 gas molecular adsorptive cross-sectional area in the complete monolayer (equal to 0.162 nm2 for N2 gas) analysis, the 22,400 represents the amount of employed volume in mL by 1 mol of N2 gas at STP.

The cylindrical shape of NaIO4-CNP adsorbent was observed from the BET plot (Fig. 3b). Findings showed that the synthesized NaIO4-CNP adsorbent has a higher SSA of 124.82 m2g−1. Therefore, NaIO4-CNP adsorbent has shown the higher methylene blue dye adsorption competence owing to the decline and increase of NaIO4-CNP adsorbent particle size and SSA, respectively observed from BET data analysis.

3.2 Treatment of the real textile wastewater (WW) relative to synthetic solution

The collected SERWW physicochemical analysis values were showed in the Table 1. As seen in the Table 1, the pH average value was indicated nearly acidic nature. Subsequently, the SERWW average values for COD, BOD, EC, NO3−, SO42−, PO43−, Cl−, Ca2+, Mg2+, Cu2+ were indicated that there are the presence of positively and negatively charged species that were found in the collected SERWW and reacts with the MB day cations in the adsorption mechanisms. The adsorption procedures were accomplished through the use of 30 mL of SERWW with 0.07, 0.4, 0.9, 1.4, and 2 g of NaIO4-CNP adsorbent dose for 50 min. of reaction time at room temperature. From equilibrium condition, the equilibrium value for the NaIO4-CNP dose were 0.9 g, this is due to at this dose the greater value were perceived. Figure 4 be necessary been revealed that the absorbance spectra of MB solution (a) and real SERWW (b), respectively, previously and subsequently action and the appraisal study for the adsorption ability of MB from synthetic solution and real textile industrial SERWW(c).

Table 1 The SERWW physico-chemical analysis study
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Fig. 4
figure 4

UV–Visible spectra of synthetic MB (a) real textile wastewater (b) before and after 60 min. of treatment at λmax of 664, and the comparison study for the uptake capacity of MB from synthetic wastewater and real textile industrial WW solutions (c)

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The UV–Vis spectra indicated that the percent removal (%R) of synthetic solution was advanced relative to that of the real textile industrial SERWW. The conclusion might be resulted; the real system was slowed down by the existence of diverse conditions that participates with the MB dye. The reduced results was observed after treatment and given in Table 1. In conclusion, the levels of COD, Cl−, Mg2+, and Cu2+ reduced by nearly 95%, 100%, 93%, and 95% correspondingly. Additionally, the appraisal study was accompanied and accessible in Fig. 4c. The results indicated that a very high %R (99.99%) of MB cations was removed from standard solution and relatively less %R (78.5%) of MB cations was removed from real textile industrial SERWW by using 0.9 g NaIO4-CNP and 30 mg/L initial concentration and 50 min. interaction period of time. The high differences observed between the results arise from the presence of competing cations in the collected SERWW.

3.3 Adsorption experiments

3.3.1 Effect of interaction periods of time

Studying the effect of contact time on the adsorption of MB day cations in the SERWW was very important because, it governs the degree of an adsorption process [39]. The effect of interaction periods of time on the adsorption of MB day cations in the SERWW was accompanied through varying the interaction periods of time from 10 to 90 min. at optimum dosage of 0.5 g for NaIO4-CNP, 25 °C of temperature (T), and MB cations initial concentration of 30 mg L−1 can be given in Fig. 5a. The greater adsorption processes were perceived by increasing the interaction periods of time ranged from 30 to 180 min for S-CNP adsorbent. This is due to the availability of large number vacant spaces in the NaIO4-CNP adsorbent [38, 39]. The NaIO4-CNP adsorbent maximum % removal (%R) of MB cations were 84% and 95.0%, respectively, was perceived at the optimum periods of time equal to 120 min for MB cations, in that order. Beyond this, the MB dye uptake processes attempts the equilibrium position and proceeded with a fixed manner. This result agrees with findings informed by Mohammad et al. [3], on MB dye adsorbed onto cellulose based material.

Fig. 5
figure 5

Effect of interaction periods of time (a) and NaIO4-CNP adsorbent dose (b) for the removal of MB dye cations from SERWW, correspondingly, at optimum (temperature of 25 °C, MB dye concentration of 30 mg/L, and solution pH of 8.5)

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3.3.2 Effect of adsorbent dose

As seen in the Fig. 5b, the effects of NaIO4-CNP dosage on the (%R) of MB dye from the SERWW showed that 85.2% can be eliminated from SERWW through the use of NaIO4-CNP adsorbent with optimum NaIO4-CNP dose of 1 g at room temperature. The relatively greater %R for MB dye was observed through the use of NaIO4-CNP adsorbent than S-CNP adsorbent used previously [18] may be because of the NaIO4 nature. After the optimum NaIO4-CNP adsorbent, the adsorption competence declined. This is predicted as a result of the fact that at augmented concentration levels of nanosorbent (NaIO4-CNP) large number of vacant spaces available for the metal ions. No matter how, at augmented concentration levels there is no additional augmentation in adsorption mechanism because of the amount of MB dye ions bonded to the NaIO4-CNP adsorbent and the number of movable ions in the SERWW turn into fixed even by extra accumulation of the NaIO4-CNP adsorbent dose [41].

3.3.3 Effect of solution pH and initial levels

Studying the effect of solution pH on the adsorption of MB day cations in the SERWW was very important because, it provides the information for adsorption mechanism [26]. As seen in the Fig. 6a, the influences of solution pH and initial levels of MB dye cations on the %R of MB dye in the SERWW through the use of NaIO4-CNP adsorbent. NaIO4-CNP adsorbent showed increasing adsorption capabilities in the range of solution pH between 2 and 5. Correspondingly, the higher %R competence of NaIO4-CNP adsorbent was 85.5 at pH equal to 8.5. At acidic pH, the reaction of MB dye cations with NaIO4-CNP adsorbent is diminished as a result of the interference of H+ ions to the NaIO4-CNP adsorbent surfaces. Conversely, as the SERWW pH approaches to neutral level, MB dye adsorption to the NaIO4-CNP adsorbent surface increases. Beyond this point, increase in pH value was recorded because of the increased concentration of OH− ions and as result the reduced %R of MB dye observed. Supporting this result Kara et al. [18] reported the higher %R of MB ions at closely comparable values of pH. At basic pH values, the MB dye was precipitated as their hydroxides.

Fig. 6
figure 6

Effect of solution pH (a) and initial concentration (b) for the removal of MB dye from SERWW, correspondingly, at optimum (temperature of 25 °C, NaIO4-CNP dose of 1 g, and interaction periods of time equal to 60 min.)

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MB dye ions initial concentration (Ci) effect for the adsorption mechanism by NaIO4-CNP adsorbent was represented (Fig. 6b). At the starting point, the adsorption reaction going as fast as and in a very short periods of time it attains the equilibrium value of 30 mg L−1. The quicker metal uptake processes at starting point, was as a result of the large unoccupied spaces of the NaIO4-CNP adsorbent surface. At this stage, the NaIO4-CNP adsorbent clearly displayed higher MB dye cations uptake competence. This is happen as a result of the comparatively augmented SSA of NaIO4-CNP adsorbent which was observed by the reaction of CNP with carbonyl group providing chemical [18].

3.4 Adsorption isotherms

The adsorption mechanisms fits well to Freundlich isotherm model for MB dye cations removal (Fig. 7a, b). Obviously, these isotherm models tells the spreading of the MB dye cations amongst the fluid and crystalline states on the basis of prospects associated upon the varied or unvaried situations of the NaIO4-CNP spaces, the assembly of exposure, and the panorama of interaction. Linear equations of the Langmuir isotherm and Freundlich isotherm was exemplified in (Eqs. 4 and 5), respectively. Moreover, the value for a dimensionless equilibrium parameter (KL) is measured through the use of Eq. 6 for the confirmation of feasibility for MB dye cations sorption on NaIO4-CNP sorbent. Table 2 indicated the measured Langmuir and Freundlich isotherm constituent values. As seen in the Table 2, the regression values for Langmuir and Freundlich isotherm model through the use of NaIO4-CNP sorbent was 0.962 and 0.980, respectively, for MB dye cations removal. From this value the adsorption mechanisms fits to the Freundlich isotherm model. Furthermore, the measured amounts of the Langmuir constant b of NaIO4-CNP sorbent for MB dye cations uptake were 0.589 Lmg−1, respectively. As conclusion, it recommends the opportunity of adsorption mechanisms. Additionally, the quantity of Kf and n of NaIO4-CNP adsorbent for MB dye adsorption was 1.032 and 1.033, respectively. From the findings, one can conclude that the improved MB dye adsorption capability as well as intensity, respectively. The higher MB dye adsorption efficiency (qmax) of the NaIO4-CNP adsorbents in the given unit mass was 62.91. The results showed that the NaIO4-CNP adsorbent used have high pollutant removal capacity in general and MB dye cations removal efficiency in particular.

$$\frac{C_e }{{Q_e }} = \frac{1}{{bQ_{\max } }} + \frac{C_e }{{Q_{\max } }}$$
(4)
$$logqe = \log k_f + \frac{1}{n}\log Ce$$
(5)
$$R_L = \frac{1}{1 + bC_0 }$$
(6)
Fig. 7
figure 7

Langmuir (a) and Freundlich (b) adsorption isotherm for the MB dye removal, respectively, at Ci = 30 mg/L, pH = 8, adsorbent dose = 1 g and contact time = 60 min

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Table 2 Langmuir and Freundlich isotherm constants for cationic MB dye uptake by NC and NaIO4-NC sorbent at 25 °C
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3.5 Rate of adsorption

The rates of MB dye cations adsorption by NaIO4-CNP adsorbent was performed through the use of linear pseudo-first order (Eq. 7) and linear pseudo second order (Eq. 8), correspondingly. Its plot was plotted through Ce vs. Ce/qe and log qe versus log Ce plot was given in Fig. 8a, b, correspondingly.

$$\log (qe - qt) = \log qe - \frac{K_1 t}{{2.303}}$$
(7)
$$\frac{t}{q_t } = \frac{1}{K_2 q_e^2 } + \frac{t}{q_e }$$
(8)
Fig. 8
figure 8

Plot of the PFO (a) and PSO (b) kinetics model at Ci = 30 mg/L, pH = 8.5, adsorbent dose = 1 g and contact time = 60 min for cationic MB dye removal, respectively

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The regression investigational data found through the use of pseudo-first order (PFO) kinetics model was invalid for the sorption procedure due to the investigational qe number was much dissimilar than the measured qe value for NaIO4-CNP adsorbent. The findings specified that the rate of adsorption mechanism not fit PFO kinetics. Thus, Fig. 8a, b showed a pseudo second order (PSO) kinetics model fits the study data well for MB dye adsorption on NaIO4-CNP sorbent.

In line with this similar research was reported by Kara et al. [18] on cationic MB dye from wastewater through the use of CNMs prepared from Eichhornia crassipes. The kinetic data was found from Fig. 8a, b and given in Table 3. The kinetics study provides higher regression values (R2 = 0.985 and 0.991, for PSO) and below satisfactory regression values (R2 = 0.764 and 0.972, for PFO) in NaIO4-CNP adsorbent for MB removal, correspondingly.

Table 3 The values of parameters and correlation coefficients of Pseudo second order (PFO) and Pseudo second order (PSO) kinetics
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3.6 Regeneration

NaIO4-CNP adsorbent regeneration investigation was accomplished to substantiate the reusability of the NaIO4-CNP adsorbent for actual application and given in Fig. 9. This experiment was done firstly by desorbing the MB dye from NaIO4-CNP adsorbent with the help of ethanol desorption eluent through batch experiment. From the experiment, the findings shown that the NaIO4-CNP adsorbent MB dye uptake competence gradually reductions with increasing rounds of recyclable experimental. The reduction in uptake competence of the NaIO4-CNP adsorbent with augmented recyclable periods of times is customarily owing to the decrease of specific surface area found for the NaIO4-CNP adsorbent. Satisfied recyclability by increasing MB dye uptake competence for the used sorbent postulates the operative sorbent of NaIO4-CNP sorbent for manipulating in the uptake of contaminants. From this, one can easily understood that the adsorption competency of the NaIO4-CNP sorbent does not meaningfully alter afterward 5th rounds of experiment as the %R is still high. Results indicated that reduces in %R for the 5 uninterrupted rounds were no more than 5%. From this point of view, one can concluded that NaIO4-CNP adsorbent can be used as contaminant removals for extended time with an increasing opportunity. This conclusion is in line with research conducted by Kara et al. [42] for the uptake of cadmium metal ions from actual wastewater through the use of CNMs adsorbent.

Fig. 9
figure 9

Percentage removal of cationic MB dye after different cycles (1st, 3rd and 5th) by NaIO4-CNP sorbent

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4 Conclusion

The NaIO4-CNP adsorbent was fabricated through chemically and makes use of a low-cost, renewable, and high uptake competences adsorbent for the adsorption of methylene blue dye in SERWW. The removal competence of this sorbent toward MB dye cations from real wastewater in comparison with synthetic solution was less may be the presence of other interferences present in real wastewater. The anticipated pollutant uptake mechanism for the study under optimized condition of NaIO4-CNP sorbent mostly incorporated the reaction of carbonyl and hydroxyl groups of NaIO4-CNP adsorbent and MB dye cations. From this point view, the recycled sorbent displayed the higher MB dye cation adsorption competence. The MB dye cations adsorption mechanisms for NaIO4-CNP sorbent system was fitted with Frindlich isotherm. Also, the kinetics of the reaction between the MB dye cation and NaIO4-CNP sorbent was expressed by PSO kinetics model. The regeneration experimentation result revealed that the recycled adsorbent was easily generable and cautiously welcoming used for consecutive 5th rounds as sorbent for contaminant removals without greater loss.