Weizhao Yin

• Doctor of Philosophy
• Professor (Associate) at Jinan University

Zero-valent iron (Fe0) is restricted in phosphate removal due to the formation of a passive P-Fe layer on its surface. A micro-electric field (0.20 mA cm-2) was employed in Fe0 column to facilitate iron corrosion for enhanced phosphate removal with a Fe0 column as the control. The performance of two columns was compared by batch experiment at a Fe0...

Tetrasphaera-enhanced biological phosphorus removal (T-EBPR) was developed by augmenting conventional EBPR (C-EBPR) with Tetrasphaera to improve phosphorus removal from anaerobic digestate of swine wastewater. At influent total phosphorus (TP) concentrations of 45 to 55 mg/L, T-EBPR achieved effluent TP concentration of 4.17 ± 1.02 mg/L, 54% lower...

The removal of Cr(VI) from groundwater by zero-valent iron (Fe0) and microorganisms under different nutrients and electron-accepting conditions was investigated using continuously-flowed column reactors with an abiotic Fe0 column as the control. Both abiotic and biotic Fe0 columns were operated at low and relatively high concentrations of organic s...

Mercury speciation in groundwater affects its removal effectiveness and methylation potential. Yet, most studies focus on the removal of inorganic dissolved Hg(II) and few studies explored the mercury methylation before and after the treatment. This study comprehensively explored the removal performance of three model mercury species, namely, disso...

In this work, zero-valent iron (ZVI) combined with anaerobic bacteria was used in the remediation of Cd(II)-polluted soil under the mediation of sulfate (SO42-). Owing to hydrogen-autotrophic sulfate reduction, serious corrosion occurred on sulfate-mediated biotic ZVI in terms of solid phase characterization as massive corrosive products (e.g., goe...

Trichloroethylene (TCE) is a notorious persistent pollutant in groundwater, while most reductive dechlorination processes result in the formation of toxic less-chlorinated by-products. In this work, adsorbed atomic hydrogen (H*) was produced by Pd(II) doped Fe(OH)2, which was used for ultra-fast reductive dechlorination of TCE without the formation...

In this study, an integrated system of Fe⁰ and hydrogenotrophic microbes mediated by nitrate (nitrate-mediated bio-Fe⁰, NMB-Fe⁰) was established to remediate Cd(II)-contaminated sediment. Solid phase characterization confirmed that aqueous Cd(II) (Cd(II)aq) was successfully immobilized and enriched on iron surface due to promoted iron corrosion dri...

In this study, nano-sized silver oxides were loaded on activated carbon (nAg2O/AC) through a facile impregnation-calcination method for enhanced bacterial inactivation from drinking water, in which Escherichia coli (E. coli) was used as target bacteria. XRD and SEM characterization confirmed that nano-sized Ag2O particles (50–200 nm) were successfu...

Green rust and bone char (GR-BC) mixture is reported as an effective reducing reagent for chlorinated ethenes dehalogenation. However, surfactant amendment might be required before the injection of GR-BC into the contaminated sites, which could enable better distribution of the reagent and even better dehalogenation performance. In this study, diff...

Activated carbon-supported goethite (α[email protected]) was prepared by a simple impregnation method to catalyze hydrogen peroxide (H2O2) for effective inactivation of Escherichia coli (E. coli) with α-FeOOH and AC as controls. As expected, α-FeOOH particles were uniformly distributed on AC surfaces and surface-bound Fe(III) was partially converte...

The prevailing view is that dehalogenation of chlorinated ethene by Fe(OH)2 or adsorbed Fe²⁺ alone is extremely slow or impossible. In this study, a novel composite was prepared by facile mixing of Fe²⁺, NaOH, and bone char (BC) at room temperature, providing an unprecedented trichloroethene (TCE) dechlorination rate. In the fastest dehalogenation...

In this study, hydrogen-autotrophic microorganisms and zero-valent iron (Fe⁰) were filled into columns to investigate hydrogenotrophic denitrification effect on cadmium (Cd(II)) removal and column life-span with sand, microorganisms, Fe⁰ and bio-Fe⁰ columns as controls. In terms of the experiment results, the nitrate-mediated bio-Fe⁰ column showed...

Green rusts (GRs) are materials with strong reducing ability useful for soil and groundwater remediation. In this study, we synthesized GRCl-Si with green rust chloride (GRCl) by using silicate for stabilization and evaluated its capacity for simultaneous removal of Cr(VI) and carbon tetrachloride (CT). Cr(VI) acted as a promoter to accelerate CT r...

The removal of Cr(VI) from groundwater by zero-valent iron (Fe ⁰ ) and microorganisms under different nutrients and electron-accepting conditions was investigated using continuously-flowed column reactors with an abiotic Fe ⁰ column as the control. Both abiotic and biotic Fe ⁰ columns were operated at low and relatively high concentrations of organ...

In this study, oxidants including hydrogen peroxide (H2O2), hypochlorite (ClO⁻) and persulfate (S2O8²⁻) were employed to promote zero-valent iron (ZVI) corrosion and enhance phosphate (P) removal from water through batch and breakthrough experiments. Characterization results indicated that the addition of oxidant can cause large-scale corrosion of...

Antimony (Sb) and arsenic (As) pollution in water has become a major concern in the world due to their toxicity and adverse effects to environmental quality and human health. Among the existing remediation technologies for Sb and As pollution control, sorption via iron-based materials has attracted increasing attention since they possess advantages...

A biotic iron (Fe0) treatment system combined with mixed microorganisms was applied to remediate cadmium (Cd)-contaminated groundwater under the intervention of sulfate. Due to hydrogenotrophic desulfuration effect, severe iron corrosion was observed in this microbe-collaborative Fe0 system according to surface morphology analysis as lots of second...

In this study, a collaborative system of Fe⁰ and mixed anaerobic microorganisms was established for remediating chromium (Cr)‐contaminated soil and restraining the translocation of Cr from soil to swamp cabbage (Ipomoea aquatica Forssk.). Solid phase characterization demonstrated that more reactive secondary minerals such as green rust, magnetite,...

Electrochemical dechlorination is a prospective strategy to remediate trichloroethylene (TCE)-contaminated groundwater. In this work, iron-nitrogen-doped carbon (FeNC) mimicking microbiological dechlorination coenzymes was developed for TCE removal under environmentally related conditions. The biomimetic FeNC-900, FeNC-1000, and FeNC-1100 materials...

Bone char catalyzed dechlorination of trichloroethylene (TCE) by green rust (iron(II)-iron(III) hydroxide, GR) has introduced a promising new reaction platform for degradation of chlorinated solvents. This study aimed to reveal whether a broader class of biochars are catalytically active for the dechlorination reaction and to identify which biochar...

In this study, nano α-FeOOH (nFeOOH, 100–500 nm) was coated onto activated carbon ([email protected]) through a dipping means for enhanced Cr(VI) immobilization from drinking water. The [email protected] significantly improved the Cr(VI) removal from 19.9% (AC control) to 93.4%. XPS spectra and chromium speciation demonstrated that about 90% of ads...

A novel macroporous strong acidic cation exchange resin (D001) modified by nano-sized goethite (nFeOOH@D001) was fabricated by using a facile ethanol dispersion and impregnation method, and its efficiency for Cr(VI) removal was tested thereafter. Due to the dispersing effect of ethanol, FeOOH particles of 20–150 nm were coated on the D001 surfaces....

In this study, carboxymethyl cellulose (CMC) was employed to stabilize zero-valent iron nanoparticles (CMC-nFe⁰) to improve their dispersity and antioxidation for enhanced hexavalent chromium (Cr(VI)) removal. Scanning electron microscope (SEM) observation revealed that the nFe⁰ agglomerated in clusters, while the CMC-nFe⁰ connected as chains and p...

Green rusts (GRs) are redox active towards contaminants but they are not stable for long distance transport during the soil and groundwater remediation. In this study, green rust chloride (GR) was stabilized by selected regents, including silicate (Si), phosphate (P), fulvic acid (FA), carboxymethyl cellulose (CMC) and bone char (BC), then these st...

In this study, nitrate mediated biotic zero-valent iron (Fe⁰) corrosion was employed to enhance cadmium (Cd) removal from groundwater. In comparison with a 17.5% Cd(II) removal treated with abiotic Fe⁰, a 3.9 times higher Cd(II) removal of 86.2% was recorded in the nitrate-mediated biotic Fe⁰ system. Solids phase characterization confirmed that bio...

Continuous‐flow iron and bio‐iron columns were used to evaluate the effects of seepage velocity and concentration on Cr(VI) removal from groundwater. Solid‐phase analysis showed that microorganisms accelerated iron corrosion by excreting extracellular polymeric substances and generated highly reactive minerals containing Fe(II), which gave the bio‐...

Biochars function as electron transfer mediators and thus catalyze redox transformations of environmental pollutants. A previous study has shown that bone char (BC) has high catalytic activity for reduction of chlorinated ethylenes using layered Fe(II)-Fe(III) hydroxide (green rust) as reductant. In the present study, we have studied the rate of tr...

A collaborative system of carboxymethyl cellulose stabilized nanosized zero-valent iron (CMC-nFe0) and microorganisms was set up to enhance the stabilization of Cr(VI) in soil. In comparison with an aqueous-bound Cr(VI) removal of 18.9% in the nFe0 system, a higher Cr(VI) removal of 68.9% was achieved in the nFe0 and microorganisms system after 14...

Layered iron(II)-iron(III) hydroxides (green rusts, GRs) constitute fast reductants for chlorinated methanes while most studies of GRs reaction with chlorinated ethylenes (CEs) have reported little or no reduction. In this work, we demonstrate that bone char (BC) can break the kinetic hindrance of CEs dehalogenation by GR. Dechlorination of perchlo...

Activated carbon-coated α-Fe2O3 nanoparticles (nFe2O3@AC) were synthesized by a facile impregnation method to enhance hexavalent chromium (Cr(VI)) removal from water. The SEM images confirmed that α-Fe2O3 particles ranging from 90 to 500 nm were dispersedly loaded on the AC, which successfully amended Cr(VI) removal. The nFe2O3@AC was able to remov...

Currently, black-odor river has received great attention in China. In this study, the micro-nano bubble technology (MBT) was used to mitigate the water pollution rapidly and continuously by increasing the concentration of dissolved oxygen (DO) in water. During treatment, the concentration of DO increased from 0.60 mg/L to over 5.00 mg/L, and the ox...

Metal-activated persulfate is an efficient reagent for the oxidative degradation of organic contaminants. However, homogenous catalytic activation of persulfate has the drawbacks of narrow pH range and metal ion contamination. Here, we designed a heterogeneous system for persulfate activation by green rust irradiated with ultraviolet light-emitting...

In this study, activated carbon (AC) was modified with micro-sized geothite (mFeOOH) using a facile and cost-effective impregnation method for enhanced Cr(VI) removal from aqueous solutions. X-ray diffraction (XRD) and scanning electron microscope (SEM) analysis showed that FeOOH particles with a diameter of 0.1-1 μm were dispersed homogeneously on...

Layered FeII-FeIII hydroxide chloride (chloride green rust, GRCl) has high reactivity towards reducible pollutants such as chlorinated solvents. However, this reactive solid is prone to dissolution, and hence loss of reactivity during storage and handling. In this study, adsorption of silicate (Si) to GRCl was tested for its ability to minimize GRC...

In this study, a sequential Fe0/H2O2 reaction and biological process was employed as a low-cost depth treatment method to remove recalcitrant compounds from coal-chemical engineering wastewater after regular biological treatment. First of all, a chemical oxygen demand (COD) and color removal efficiency of 66 and 63% was achieved at initial pH of 6....

A layered Fe(II)-Fe(III) hydroxide (green rust, GR) was intercalated with dodecanoate (known as GRC12) and then amended with Cu(II) (GRC12(Cu)) before reaction with chloroform (CF), carbon tetrachloride (CT), trichloroethylene (TCE) or tetrachloroethylene (PCE). Reduction of CT by GRC12(Cu) was 37 times faster than with GRC12 alone before the activ...

In this study, Fe⁰ and mixed anaerobic culture were integrated in one column to investigate the coupled abiotic and biotic effects on hexa-valent chromium (Cr(VI)) removal and column longevity with an abiotic Fe⁰ column in the control experiments. According to the breakthrough study, a slower Cr(VI) breakthrough rate of 0.19 cm/PV was observed in t...

Layered FeII-FeIII hydroxides (green rusts, GR) are promising reactants for reductive dechlorination of chlorinated solvents due to high reaction rates and the opportunity to inject reactive slurries of the compounds into contaminant plumes. However, it is necessary to develop strategies that reduce the formation of toxic by-products such as chloro...

A one-pot bio-iron system was established to investigate synergetic abiotic and biotic effects between iron and microorganisms on Cr(VI) removal. More diverse iron corrosion and reactive solids, such as green rusts, lepidocrocite and magnetite were found in the bio-iron system than in the Fe⁰-H2O system, leading to 4.3 times higher Cr(VI) removal e...

Layered FeII–FeIII hydroxides (green rusts, GRs) are efficient reducing agents against oxidizing contaminants such as chromate, nitrate, selenite, and nitroaromatic compounds and chlorinated solvents. In this study, we adopted a buffered precipitation approach where glycine (GLY) was used in the synthesis of sulfate-interlayered GR (GRSO4) by aeria...

This study investigated the effects of varying nitrobenzene (NB) loadings via increasing flow rate or influent NB concentration mode on the removal efficiency in zero-valent iron (ZVI) columns sterilized (abiotic) or preloaded with acclimated microorganisms (biotic). It was shown that physical sequestration via adsorption/co-precipitation and reduc...

Pure zero-valent iron (ZVI) has poor catalytic capacity due to its agglomeration and slow corrosion rate in neutral solution and hence requires acid condition for heterogeneous Fenton reaction. In this study, we develop an activated carbon (AC)-supported ZVI catalyst (AC-Fe0) that was prepared with a one-step reductive roasting method by employing...

Batch experiment was conducted to evaluate the capability of a biotic Fe0–H2O for nitrobenzene (NB) removal from groundwater. In this study, iron dosage was 0.25 g L−1 throughout the whole experiment and the Fe0–H2O system was amended with 180 mg L−1 VSS of mixed culture. The biotic system was tested at low concentrations (50 mg L−1 as COD) of orga...

Nitrobenzene (NB) infiltrated in groundwater has caused serious threats to the safety of drinking water due to its persistence and high toxicity. In this study, abiotic zero-valent iron (ZVI) column and biotic ZVI column were employed to investigate abiotic and biotic effects between iron and microorganisms on NB removal and column longevity. Physi...

Sequential upflow anaerobic filter (UAF)/air lift (ALR) reactors were employed to investigate the effects of hydraulic retention time (HRT) and nitrobenzene (NB) concentration on treatment of NB-containing wastewater. The results showed that NB was effectively reduced to aniline (AN) with glucose as co-substrate in the UAF reactor. The AN and the r...

Nitrobenzene (NB) in groundwater has posed significant health risks because of its persistence and high toxicity. In this study, batch experiments were performed to evaluate the effects of initial pH, iron dosage, oxygen and common dissolved anions including Cl−, SO42−, NO3−, HCO3−, PO43− and humic acid on the NB reduction by zero-valent iron (ZVI)...

The decoloration of an azo dye reactive brilliant orange (X-GN) by a heterogeneous Fenton system using activated carbon-FeOOH catalyst (AC-FeOOH) and H(2)O(2) was studied. Under typical conditions (pH 7.0, H(2)O(2) 10 mmol/L, AC-FeOOH 1.0 g/L and 30 °C), 98% decoloration rate of X-GN was achieved in 240 min. The decoloration efficiency of X-GN incr...