Rapid and efficient recovery of silver with nanoscale zerovalent iron supported on high performance activated carbon derived from straw biomass

This study proposed a sequential redox process to partially degrade tetrabromobisphenol A (TBBPA) within a reactor to a great extent. After 72 hours in an anoxic environment, 20 ppm of TBBPA could be effectively degraded by sulfurized zerovalent iron nanoparticles (S-nZVI) at concentrations of 2 g L-1 and 4 g L-1. Biphenol A (BPA) together with tri-, di-, and monobromobisphenol A was detected by high-performance liquid chromatography (HPLC) suggesting that TBBPA was debrominated by S-nZVI in a stepwise manner. Following the S-nZVI treatment, a persulfate-advanced oxidation process (PS-AOP) system with persulfate concentrations varied from 5 to 20 mM was incorporated to degrade the final debrominated byproduct, BPA, for 2 hours. The two-stage anoxic/oxic reactions at the same reactor with initial conditions (0.037 mM TBBPA, 4 g L-1 of S-nZVI, pH 6 in anoxic stage, 20 mM of PS in the latter oxic stage) were investigated. The sulfurized layer played an important role in such a system and hypothetically contributes to increasing electron transfer from Fe0 core as well as hydrophobicity of the NP surface. It was demonstrated that the S-nZVI/PS-AOP system could effectively remediate TBBPA and BPA and consequently provide a promising strategy to remedy brominated organic pollutants in the environment.

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Chromium (VI) removal from water using starch coated nanoscale zerovalent iron particles supported on activated carbon

Chemical Engineering Communications ◽

10.1080/00986445.2018.1521390 ◽

2018 ◽

Vol 206 (6) ◽

pp. 708-715 ◽

Cited By ~ 2

Author(s):

Bin Ji ◽

Yaorong Shu ◽

Yuexin Li ◽

Jiale Wang ◽

Yuting Shi ◽

...

Keyword(s):

Activated Carbon ◽

Zerovalent Iron ◽

Iron Particles ◽

Chromium Vi ◽

Nanoscale Zerovalent Iron

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Use of activated carbon to remove undesirable residual amylase from refinery streams

Sugar Industry ◽

10.36961/si18170 ◽

2017 ◽

pp. 96-103 ◽

Cited By ~ 1

Author(s):

Gillian Eggleston ◽

Isabel Lima ◽

Emmanuel Sarir ◽

Jack Thompson ◽

John Zatlokovicz ◽

...

Keyword(s):

Activated Carbon ◽

High Temperature ◽

High Performance ◽

Activated Carbons ◽

Amylase Activity ◽

Sugar Industry ◽

End User ◽

Customer Complaints ◽

Carry Over ◽

Very High

In recent years, there has been increased world-wide concern over residual (carry-over) activity of mostly high temperature (HT) and very high temperature (VHT) stable amylases in white, refined sugars from refineries to various food and end-user industries. HT and VHT stable amylases were developed for much larger markets than the sugar industry with harsher processing conditions. There is an urgent need in the sugar industry to be able to remove or inactivate residual, active amylases either in factory or refinery streams or both. A survey of refineries that used amylase and had activated carbon systems for decolorizing, revealed they did not have any customer complaints for residual amylase. The use of high performance activated carbons to remove residual amylase activity was investigated using a Phadebas® method created for the sugar industry to measure residual amylase in syrups. Ability to remove residual amylase protein was dependent on the surface area of the powdered activated carbons as well as mixing (retention) time. The activated carbon also had the additional benefit of removing color and insoluble starch.

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