Application of response surface methodology for optimization of Co(II) removal from synthetic wastewater by adsorption on NiO nanoparticles

This paper proposes an improved optimisation of sequencing batch reactors (SBR) for aerobic granular sludge (AGS) at high temperature-low humidity for domestic wastewater treatment using response surface methodology (RSM). The main advantages of RSM are less number of experiment required and suitable for complex process. The sludge from a conventional activated sludge wastewater treatment plant and three sequencing batch reactors (SBRs) were fed with synthetic wastewater. The experiment were carried out at different high temperatures (30, 40 and 50°C) and the formation of AGS for simultaneous organics and nutrients removal were examined in 60 days. RSM is used to model and to optimize the biological parameters for chemical oxygen demand (COD) and total phosphorus removal in SBR system. The simulation results showed that at temperature of 45.33°C give the optimum condition for the total removal of COD and phosphorus, which correspond to performance index R<sup>2</sup> of 0.955 and 0.91, respectively.

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Experimental study and parameters optimization of microalgae based heavy metals removal process using a hybrid response surface methodology-crow search algorithm

Scientific Reports ◽

10.1038/s41598-020-72236-8 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

N. Sultana ◽

S. M. Zakir Hossain ◽

M. Ezzudin Mohammed ◽

M. F. Irfan ◽

B. Haq ◽

...

Keyword(s):

Heavy Metals ◽

Response Surface Methodology ◽

Response Surface ◽

Removal Efficiency ◽

Search Algorithm ◽

Synthetic Wastewater ◽

Order Kinetic ◽

Optimum Conditions ◽

Microalgal Biomass ◽

Multiple Heavy Metals

Abstract This study investigates the use of microalgae as a biosorbent to eliminate heavy metals ions from wastewater. The Chlorella kessleri microalgae species was employed to biosorb heavy metals from synthetic wastewater specimens. FTIR, and SEM/XRD analyses were utilized to characterize the microalgal biomass (the adsorbent). The experiments were conducted with several process parameters, including initial solution pH, temperature, and microalgae biomass dose. In order to secure the best experimental conditions, the optimum parameters were estimated using an integrated response surface methodology (RSM), desirability function (DF), and crow search algorithm (CSA) modeling approach. A maximum lead(II) removal efficiency of 99.54% was identified by the RSM–DF platform with the following optimal set of parameters: pH of 6.34, temperature of 27.71 °C, and biomass dosage of 1.5 g L−1. The hybrid RSM–CSA approach provided a globally optimal solution that was similar to the results obtained by the RSM–DF approach. The consistency of the model-predicted optimum conditions was confirmed by conducting experiments under those conditions. It was found that the experimental removal efficiency (97.1%) under optimum conditions was very close (less than a 5% error) to the model-predicted value. The lead(II) biosorption process was better demonstrated by the pseudo-second order kinetic model. Finally, simultaneous removal of metals from wastewater samples containing a mixture of multiple heavy metals was investigated. The removal efficiency of each heavy metal was found to be in the following order: Pb(II) > Co(II) > Cu(II) > Cd(II) > Cr(II).

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OPTIMIZATION OF ACTIVATED CARBON SYNTHESIS USING RESPONSE SURFACE METHODOLOGY TO ENHANCE H2S REMOVAL FROM REFINERY WASTEWATER

Journal of Chemical Engineering and Industrial Biotechnology ◽

10.15282/jceib.v1i1.3715 ◽

1970 ◽

Vol 1 (1) ◽

pp. 1-17

Author(s):

Omar Abed Habeeb ◽

Ramesh Kanthasamy ◽

Gomaa A. M. Ali ◽

Rosli Mohd Yunus

Keyword(s):

Response Surface Methodology ◽

Activated Carbon ◽

Response Surface ◽

Chemical Activation ◽

Synthetic Wastewater ◽

Quadratic Model ◽

Activation Time ◽

Activation Temperature ◽

Impregnation Ratio ◽

Influential Variable

The main point of this study is to investigate the optimal conditions for preparation of activated carbon from wood sawdust (ACWSD) for removal of hydrogen sulfide (H2S) from wastewater. The response surface methodology (RSM) was employed to prepare the ACWSD by chemical activation with potassium hydroxide (KOH). The threepreparation variables impact of activation temperature (724 – 1000 °C), KOH: precursor (wt%) impregnation ratio (IR) (2:1 – 4:1) and activation time (60 – 120 min) on removal efficiency (RE, %) of H2S and activated carbon yield (ACY, %) were investigated. The preparation parameters were correlated by developing a quadratic model depend on the central composite design (CCD) to the two responses. The analysis of variance (ANOVA) was identified the most influential variable on each experimental design responses. The results showed that the temperature of 854 °C, chemical impregnation ratio of 2.95 wt% and activation time of 80 min were the optimum conditions for preparation of ACWSD with responses of RE and ACY of 72.88 % and 31.89 %, respectively. It is concluded that the ACWSD was appeared to be a favorable substance for removal of dissolved H2S from synthetic wastewater.

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