Application of response surface methodology to optimize nitrate removal at low temperature by aerobic denitrificator Pseudomonas
 strain An-1

Abstract In this study, strain CC76, identified as Enterobacter sp., was tested for the reduction of Fe3+ and denitrification using immobilized pellets with strain CC76 as experimental group (IP) and immobilized pellets with strain CC76 and magnetite powder as experimental group (IPM) in the autotrophic denitrification immobilized systems (ADIS). Compared with IP, a higher nitrate removal rate was obtained with IPM by using three levels of influent Fe3+ (0, 5, and 10 mg/L), four levels of pH (5.0, 6.0, 7.0, and 8.0), and three levels of hydraulic retention time (HRT) (12, 14, and 16 h), respectively. Furthermore, response surface methodology (RSM) analysis demonstrated that the optimum removal ratios of nitrate of 87.21% (IP) and 96.27% (IPM) were observed under the following conditions: HRT of 12 h, pH of 7.0 and influent Fe3+ concentration of 5 mg/L (IP) and 1 mg/L (IPM).

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Aqueous nitrate removal by D417 resin: thermodynamic, kinetic and response surface methodology studies

Asia-Pacific Journal of Chemical Engineering ◽

10.1002/apj.650 ◽

2011 ◽

Vol 7 (6) ◽

pp. 856-867 ◽

Cited By ~ 7

Author(s):

Jinxing Ma ◽

Zhiwei Wang ◽

Zhichao Wu ◽

Tianye Wei ◽

Ying Dong

Keyword(s):

Response Surface Methodology ◽

Response Surface ◽

Nitrate Removal

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A response surface methodology approach to the optimization of controlled low-temperature vacuum dehydration

Food Research International ◽

10.1016/0963-9969(92)90019-2 ◽

1992 ◽

Vol 25 (1) ◽

pp. 1-8 ◽

Cited By ~ 22

Author(s):

V.A.-E. King ◽

R.R. Zall

Keyword(s):

Response Surface Methodology ◽

Low Temperature ◽

Response Surface ◽

Vacuum Dehydration

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Modeling of nitrate removal from aqueous solution by Fe-doped TiO2 under UV and solar irradiation using response surface methodology

Global NEST Journal ◽

10.30955/gnj.001577 ◽

2015 ◽

Vol 17 (2) ◽

pp. 379-388 ◽

Cited By ~ 3

Keyword(s):

Aqueous Solution ◽

Response Surface Methodology ◽

Solar Radiation ◽

Response Surface ◽

Removal Efficiency ◽

Nitrate Removal ◽

Operating Conditions ◽

Solar Irradiation ◽

Design Matrix ◽

Statistical Tool

<div> Nitrate is a common groundwater pollutant all over the world. In some regions of Iran, its levels are high enough to cause serious problems to human health and the environment. The objectives of this work were to evaluate the efficiency of Fe-doped TiO2 nanoparticles at removing nitrate from aqueous solutions under UV and solar radiation and to model nitrate removal using response surface methodology techniques. In this study, a response surface methodology based on the Box–Behnken design matrix was used to describe the process of nitrate removal from an aqueous solution with four independent parameters, namely Fe-doped TiO2 (dose 1-2 g l-1), nitrate concentration (25-100 mg l-1), contact time (10-120 min), and pH (4-9). The results indicated that the removal efficiency of nitrate in the presence of ultraviolet and solar radiation was 56.5 % and 21.8%, respectively. The removal efficiency of nitrate increased with time and initial concentration of nitrate. Analysis of variance (ANOVA) indicated that the proposed model was essentially in accordance with the experimental results with the correlation coefficient R2 = 0.9237 and Adj-R2 = 0.8347. Response surface methodology (RSM) proved to be a powerful statistical tool for investigating the operating conditions for nitrate removal under UV irradiation. </div>

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Comparison of Low-Temperature Alkali/Urea Pretreatments for Ethanol Production from Wheat Straw

Journal of Biobased Materials and Bioenergy ◽

10.1166/jbmb.2021.2062 ◽

2021 ◽

Vol 15 (3) ◽

pp. 399-407

Author(s):

Zahoor ◽

Wen Wang ◽

Xuesong Tan ◽

Qiang Yu ◽

Yongming Sun ◽

...

Keyword(s):

Response Surface Methodology ◽

Enzymatic Hydrolysis ◽

Low Temperature ◽

Ethanol Production ◽

Wheat Straw ◽

Response Surface ◽

Cellulosic Ethanol ◽

Enzymatic Saccharification ◽

Hydrolysis Of ◽

Bioethanol Yield

NaOH/urea (NU) pretreatment at lower than 0 °C has been frequently applied for improving bio-conversion of lignocellulose, but the wastewater generated from the pretreatment process is hard to dispose. KOH/urea (KU) pretreatment for enhancing bioconversion of lignocellulose has recently attracted researchers’ attention due to the recycling of wastewater for facilitating crops’ growth. This study compared the effects of NU and KU pretreatments at cold conditions on the enzymatic hydrolysis and bioethanol yield from wheat straw (WS). By using response surface methodology an optimal pretreatment with an equal ratio of alkali/urea (4% w/v) at −20 °C for 3 h was established. The enzymatic hydrolysis of KU-treated WS was 81.17%, which was similar to that of NU-treated WS (83.72%) under the same condition. It means that KU pretreatment has equal ability to NU pretreatment to improve enzymatic saccharification of lignocellulose. KU pretreatment has the promising potential to replace NU pretreatment for facilitating bioconversion of lignocellulose in cold conditions due to the clean way to recycle its wastewater as fertilizer for crop growth. Hence, KU pretreatment combined with enzymatic hydrolysis and fermentation could be a promising green way to cellulosic ethanol production with zero waste emission.

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