Nitrogen doped char from anaerobically digested fiber for phosphate removal in aqueous solutions

Mood, Sohrab Haghighi; Ayiania, Michael; Jefferson-Milan, Yaime; Garcı̀a-Pèrez, Manuel

doi:10.1016/j.chemosphere.2019.124889

Cited by 41 publications

(26 citation statements)

References 65 publications

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“…The proximate composition of the N-doped char studied (moisture, fixed carbon, volatiles, and ash) was determined by using a thermogravimetric analyzer (TGA) SDTA851e (Mettler-Toledo, USA) according to ASTM standards E 871, E 1755, and E872 and Mood et al [36]. The elemental composition (CHNS-O) of the N-doped char was carried out using a TRUSPEC-CHN® (LECO, St. Joseph, MI, USA) elemental analyzer.…”

Section: Analysis Of Resulting Carbonmentioning

confidence: 99%

“…Introducing nitrogen functionalities in char structures, as a form of functionalization of a carbon surface, has been studied for several decades [23,32,36]. The production mechanism is also well understood [44].…”

Section: Catalytic Oxidation Testsmentioning

confidence: 99%

“…Activated carbons (ACs) have long been applied as inexpensive filtration adsorbents in wastewater treatment [6]. More recently, ACs produced from waste materials such as anaerobically digested fiber, rice straw, and woody wastes, referred to as chars or biochars, are being developed as catalytically active nanomaterials [19,31,36]. Like activated carbon, chars contain intersecting graphitic layers, each consisting a honeycomb of carbon atoms [16].…”

Section: Introductionmentioning

confidence: 99%

“…These layers can contain nitrogen and other heteroatomic defects, allowing for tunable surface chemistry [7,16,56,57]. Notable applications of these engineered carbonaceous materials include heterogeneous catalysts and adsorbents for pollutants such as H 2 S and CO 2 [1,4,8,36,38].…”

Section: Introductionmentioning

confidence: 99%

“…The use of active carbons in catalytic wet oxidation of phenol is not new and was well described by Santiago et al [46]. However, nitrogen doping-the act of introducing nitrogen groups in carbonaceous materials-has been shown to result in novel adsorptive and catalytic capabilities [11] not yet applied to CWO of phenol [4,36,51]. Among these are inexpensive and highly active oxidative catalysis thought to benefit from the improved electron donor/acceptor capability of nitrogen functionalities present on the catalyst surface [26].…”

Section: Introductionmentioning

confidence: 99%

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Nitrogen-doped char as a catalyst for wet oxidation of phenol-contaminated water

Tews

Garcia²,

Ayiania

et al. 2021

Biomass Conv. Bioref.

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Catalytic wet oxidation (CWO) of aqueous effluents rich in organic compounds is a very promising technology for the treatment of liquid wastes from biomass conversion processes. CWO reactions occur through the formation of free radical species, produced in the presence of an oxidant, which act on organic contaminates in the effluent. Although the reaction is well known, there exists a lack of affordable catalysts to conduct this process at the lower temperatures and pressures in novel bioenergy processes. This study assessed the catalytic effect of nitrogen-doped chars as such an option. Phenol in aqueous solution was used as a model waste effluent. Treatment was conducted at moderate temperatures (190 to 260°C), oxygen partial pressure of 1 MPa, and reaction times of 15, 30, and 45 min in stainless steel and glass-lined tube reactors. High pressure liquid chromatography (HPLC) analyses of the products quantified phenol and by-product concentrations used in the calculation of reaction activation energy. The char catalyst was studied by X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), and scanning electron microscopy (SEM) in order to gain insight into its structure and surface composition. The results indicate that nitrogen-doped char catalysts accelerate the oxidation of phenol by decreasing its reaction activation energy from 82.2 kJ/mol (non-catalyzed) to 40.4 kJ/mol (catalyzed). An analysis from first principles using density functional theory (DFT) was conducted to ascertain which N functional group has the most significant impact on free radical formation in the presence of oxygen. Among all the N functional groups studied, the dipyridinic functional groups showed the most promising characteristics to facilitate the formation of hydroxyl free radicals.

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Section: Analysis Of Resulting Carbonmentioning

confidence: 99%

Section: Catalytic Oxidation Testsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Nitrogen-doped char as a catalyst for wet oxidation of phenol-contaminated water

Tews

Garcia²,

Ayiania

et al. 2021

Biomass Conv. Bioref.

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Iron–ozone catalytic oxidation reactive filtration of municipal wastewater at field pilot and full‐scale with high‐efficiency pollutant removal and potential negative CO₂e with biochar

Baker

McCarthy²,

Taslakyan

et al. 2023

Water Environment Research

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Iron–ozone catalytic oxidation (CatOx) shows promise in addressing challenging wastewater pollutants. This study investigates a CatOx reactive filtration (Fe‐CatOx‐RF) approach with two 0.4 L/s field pilot studies and an 18‐month, 18 L/s full‐scale municipal wastewater deployment. We apply ozone to leverage common sand filtration and iron metal salts used in water treatment into a next‐generation technology. The process combines micropollutant and pathogen destructive removal with high‐efficiency phosphorus removal and recycling as a soil amendment, clean water recovery, and the potential for carbon‐negative operation with integrated biochar water treatment. A key process innovation is converting a continuously renewed iron oxide coated, moving bed sand filter into a “sacrificial iron” d‐orbital catalyst bed after adding O3 to the process stream. Results for the Fe‐CatOx‐RF pilot studies show >95% removal efficiencies for almost all >5 × LoQ detected micropollutants, with removal rates slightly increasing with biochar addition. Phosphorus removal for the pilot site with the most P‐impacted discharge was >98% with serial reactive filters. The long‐term, full‐scale Fe‐CatOx‐RF optimization trials showed single reactive filter 90% TP removal and high‐efficiency micropollutant removals for most of the compounds detected, but slightly less than the pilot site studies. TP removal decreased to a mean of 86% during the 18 L/s, 12‐month continuous operation stability trial, and micropollutant removals remained similar to the optimization trial for many detected compounds but less efficient overall. A >4.4 log reduction of fecal coliforms and E. coli in a field pilot sub‐study suggests the ability of this CatOx approach to address infectious disease concerns. Life cycle assessment modeling suggests that integrating biochar water treatment into the Fe‐CatOx‐RF process for P recovery as a soil amendment makes the overall process carbon‐negative at −1.21 kg CO2e/m3. Results indicate positive Fe‐CatOx‐RF process performance and technology readiness in full‐scale extended testing. Further work exploring operational variables is essential to establish site‐specific water quality limitations and responsive engineering approaches for process optimization. Practitioners Points Adding ozone to WRRF secondary influent flows into tertiary ferric/ferrous salt dosed sand filtration amplifies a mature reactive filtration technology into a catalytic oxidation process for micropollutant removal and disinfection. Expensive catalysts are not used. Iron oxide compounds used to remove phosphorus and other pollutants act as sacrificial catalysts with ozone, and these rejected iron compounds can be returned upstream to aid in secondary process TP removal. Biochar addition to the CatOx process improves CO2e sustainability and phosphorus removal/recovery for long‐term soil and water health. Short duration field pilot scale and 18‐month full‐scale operation at three WRRFs with good results demonstrate technology readiness.

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Preferential capture of phosphate by an Enteromorpha prolifera–based biopolymer encapsulating hydrous zirconium oxide nanoparticles

Zhong

Shen

Zhao

et al. 2021

Environ Sci Pollut Res

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Nitrogen doped char from anaerobically digested fiber for phosphate removal in aqueous solutions

Cited by 41 publications

References 65 publications

Nitrogen-doped char as a catalyst for wet oxidation of phenol-contaminated water

Nitrogen-doped char as a catalyst for wet oxidation of phenol-contaminated water

Iron–ozone catalytic oxidation reactive filtration of municipal wastewater at field pilot and full‐scale with high‐efficiency pollutant removal and potential negative CO₂e with biochar

Preferential capture of phosphate by an Enteromorpha prolifera–based biopolymer encapsulating hydrous zirconium oxide nanoparticles

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Nitrogen doped char from anaerobically digested fiber for phosphate removal in aqueous solutions

Cited by 41 publications

References 65 publications

Nitrogen-doped char as a catalyst for wet oxidation of phenol-contaminated water

Nitrogen-doped char as a catalyst for wet oxidation of phenol-contaminated water

Iron–ozone catalytic oxidation reactive filtration of municipal wastewater at field pilot and full‐scale with high‐efficiency pollutant removal and potential negative CO2e with biochar

Preferential capture of phosphate by an Enteromorpha prolifera–based biopolymer encapsulating hydrous zirconium oxide nanoparticles

Contact Info

Product

Resources

About

Iron–ozone catalytic oxidation reactive filtration of municipal wastewater at field pilot and full‐scale with high‐efficiency pollutant removal and potential negative CO₂e with biochar