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Phosphogypsum (PG) contains a lot of soluble phosphate (PO43--P) and fluorine ion (F-), which seriously has hindered the sustainable development of the phosphorous chemical industry. In this study, a new burning raw material (BRM) as an intermediate product in the cement production process was used for PO43--P and F- stabilize in PG. The stabilizing mechanism of PO43--P and F- were investigated by Fourier Transform infrared spectroscopy (FT-IR), X-ray diffractometer (XRD), Scanning Electron Microscopy (SEM), X-ray fluorescence (XRF) and X-ray spectroscopy system (XPS). The effect of PG and BRM weight ratio, solid-to-liquid ratio, reaction time, and reaction temperature on the concentrations of PO43--P and F- were studied. The results showed that the concentration of F- in the PG leaching solution was 8.65 mg/L and the stabilizing efficiency of PO43--P was 99.78%, as well as the pH of the PG leaching solution was 8.12 when the weight ratio of PG and BRM was 100:2, and the solid to liquid ratio was 4:1, reacting for 24 h at the temperature of 30 ℃. PO43--P and F- were mostly solidified as Ca5(PO4)3F, CaPO3(OH), Ca5(PO4)3(OH), Ca2P2O7·2H2O, CaSO4PO3(OH)·4H2O, CaF2, and CaFPO3·2H2O. Leaching test results indicated that the concentrations of PO43--P, F- and heavy metals were less than the integrated wastewater discharge standard (GB8978–1996). This study provides a new harmless treatment method for PG.

Solidification/stabilization (S/S) is an option for the treatment of electrolytic manganese residue (EMR). Basic burning raw material (BRM) could successfully solidify/stabilize EMR, though heavy metals S/S mechanism and long-term stability remain unclear. Herein, Mn 2+ and NH 4 + S/S behavior, hydrated BRM and S/S EMR characterization, Mn 2+ long-term leaching behavior, phase and morphology changes for long-term leaching were discussed in detail to clarify these mechanisms. Mn 2+ and NH 4 + leaching concentrations as well as pH value in S/S EMR were respectively 0.02 mg/L, 0.68 mg/L and 8.75, meeting the regulations of Chinese standard GB 8978-1996. Long-term stability of EMR was significantly enhanced after S/S. Mn 2+ leaching concentration, Mn 2+ migration, Mn 2+ cumulative release, Mn 2+ apparent diffusion coefficient and conductivity of EMR reduced to 0.05 mg/L, 5.5 × 10 -6 mg/(m 2 ·s), ~ 9 mg/m 2 , 6.30 × 10 -15 m 2 /s and 435 μs/cm. Mechanism studies showed that the hydration of BRM forms OH - , calcium silicate hydrate gels (C-S-H) and ettringite. Therefore, during S/S process, NH 4 + was escaped as NH 3 , Mn 2+ was solidified/stabilized as tephroite (Mn 2 SiO 4 ), johannsenite (CaMnSi 2 O 6 ) and davreuxite (MnAl 6 Si 4 O 17 (OH) 2 ), and Pb 2+ , Cu 2+ , Ni 2+ , Zn 2+ were solidified/stabilized by C-S-H and ettringite via substitution and encapsulation. This study provides a good choice for EMR long-term stable storage., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Electrolytic manganese residue (EMR) contains high concentrations of NH 4 + and heavy metals, such as Mn 2+ , Zn 2+ , Cu 2+ , Pb 2+ , Ni 2+ and Co 2+ , while carbide slag (CS) contains high amount of OH - and CO 3 2- , both posing a serious threat to the ecosystem. In this study, EMR and CS synergistic stabilization/solidification (S/S) was discussed science CS could stabilize or solidify EMR and simultaneously reduce its corrosive. The results showed that after the synergistic S/S for 24 h when liquid-solid ratio was 17.5% and CS dosage was 7%, Mn 2+ and NH 4 + leaching concentrations of the S/S EMR were below the detection limits (0.02 mg/L and 0.10 mg/L) with a pH value of 8.8, meeting the requirements of the Chinese integrated wastewater discharge standard (GB 8978-1996). Mn 2+ was stabilized as MnFe 2 O 4 , Mn 2 SiO 4 , CaMnSi 2 O 6 , and NH 4 + escaped as NH 3 . Zn 2+ , Cu 2+ , Pb 2+ , Ni 2+ and Co 2+ in EMR can also be stabilized/solidified because of the react with OH - and CO 3 2- in CS. Chemical cost was only $ 0.54 for per ton of EMR synergistic harmless treatment with CS. This study provided a new idea for EMR cost-effective and environment-friendly harmless treatment., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Electrolytic manganese residue (EMR) has become a barrier to the sustainable development of the electrolytic metallic manganese (EMM) industry. EMR has a great potential to harm local ecosystems and human health, due to it contains high concentrations of soluble pollutant, especially NH 4 + and Mn 2+ , and also the possible dam break risk because of its huge storage. There seems to be not a mature and stable industrial solution for EMR, though a lot of researches have been done in this area. Hence, by fully considering the EMM ecosystem, we analyzed the characteristics and eco-environmental impact of EMR, highlighted state-of-the-art technologies for EMR reduction, pretreatment, and reuse; indicated the factors that block EMR treatment and disposal; and proposed plausible and feasible suggestions to solve this problem. We hope that the results of this review could help solve the problem of EMR and thus promote the sustainable development of EMM industry., (Copyright © 2021 Elsevier B.V. All rights reserved.)

In this study, electric field and ball milling were used to leach Mn 2+ from low-grade pyrolusite (LGP). The effects of current density, reaction time, reaction temperature, ball-to-powder weight ratio, and ball milling time on the leaching efficiency of Mn 2+ from LGP as well as the leaching mechanism were systematically studied. The results showed that the combined use of electric field and ball milling enhanced the leaching of Mn 2+ from LGP. The leaching efficiency of Mn 2+ reached 97.79% under the optimum conditions of LGP-to-pyrite mass ratio of 1:0.18, current density of 30 mA/cm 2 , LGP-to-H 2 SO 4 mass ratio of 1:0.4, liquid-to-solid ratio of 5:1, ball-to-powder weight ratio of 1:1, ball milling time of 2 h, temperature of 80 °C, and leaching duration of 120 min. This value was 25.95% higher than that attained without ball milling and 41.45% higher than that attained when neither ball milling nor electric field was employed. Pyrite was fully oxidized to generate additional SO 4 2- and Fe 3+ , and was further hydrolyzed to form jarosite (KFe 3 (SO 4 ) 2 (OH) 6 ) and hydronium jarosite (Fe 3 (SO 4 ) 2 (OH) 5 ·2H 2 O) via ball milling and electric field application. Moreover, the electric field changed the surface charge distribution of the mineral particles and promoted collisions between them as well as the collapse of the crystal lattice, further improving the leaching efficiency of Mn 2+ from LGP. This study provided a new method for leaching Mn from LGP., (Copyright © 2021 The Authors. Published by Elsevier Inc. All rights reserved.)

In this study, a new electrochemical method was used to simultaneously efficient removal of Mn 2+ and NH 4 + -N in wastewater with Cu plate as cathode. The effects of various reaction parameters on the concentrations of Mn 2+ , NH 4 + -N and by-products (NO 3 - -N and NO 2 - -N, free chlorine and residual chlorine), as well as the removal mechanism were investigated. The results showed that the removal efficiencies of Mn 2+ and NH 4 + -N were 99.1% and 92.9%, and the concentrations of NO 3 - -N, NO 2 - -N, free chlorine and residue chlorine were 0.73 mg/L, 0.15 mg/L, 0.13 mg/L and 0.63 mg/L reacting for 3 h at room temperature, respectively, when the current density was 10 mA/cm 2 , the mass ratio of ClO - and Cl - was 1:1, the initial pH was 9. The concentrations of Mn 2+ , NH 4 + -N and by-products in wastewater met the integrated wastewater discharge standard (GB8978-1996). In addition, spherical manganese oxide was deposited on the anode plate, and spherical manganese oxide collapsed over electrolysis time. Manganese was mainly removed in the form of MnO, Mn(OH) 2 and MnO 2 . NH 4 + -N was mainly oxidized to N 2 . Economic evalution revealed that the treatment cost was 2.93 $/m 3 ., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Electrolytic manganese residue (EMR) is a solid waste remained in filters after using sulfuric acid to leaching manganese carbonate ore. EMR contains high concentration of soluble manganese (Mn 2+ ) and ammonia nitrogen (NH 4 + -N), which seriously pollutes the environment. In this study, a low cost of phosphate based binder for Mn 2+ and NH 4 + -N stabilization in EMR by low grade-MgO (LG-MgO) and superphosphate was studied. The effects of different types of stabilizing agent on the concentrations of NH 4 + -N and Mn 2+ , the pH of the EMR leaching solution, stabilizing mechanisms of NH 4 + -N and Mn 2+ , leaching test and economic analysis were investigated. The results shown that the pH of the EMR leaching solution was 8.07, and the concentration of Mn 2+ was 1.58 mg/L, both of which met the integrated wastewater discharge standard (GB8978-1996), as well as the concentration of NH 4 + -N decreased from 523.46 mg/L to 32 mg/L, when 4.5 wt.% LG-MgO and 8 wt.% superphosphate dosage were simultaneously used for the stabilization of EMR for 50 d Mn 2+ and NH 4 + -N were mainly stabilized by Mn 3 (PO 4 ) 2 ·2H 2 O, MnOOH, Mn 3 O 4 , Mn(H 2 PO 4 ) 2 ·2H 2 O and NH 4 MgPO 4 ·6H 2 O. Economic evaluation revealed that the treatment cost of EMR was $ 11.89/t. This study provides a low-cost materials for NH 4 + -N and Mn 2+ stabilization in EMR., (Copyright © 2020. Published by Elsevier Inc.)

The Langmuir equation, the best known adsorption model in the past century, was extensively applied to describe adsorption isotherms. The saturated adsorption amount (Q m ) obtained from the Langmuir model is an essential index to evaluate the maximum adsorption capacity of the adsorbent, which was assumed to be irrelevant to the aqueous concentration of the adsorbate. Adsorption isotherms of cadmium onto soil and biochar were performed in the current study, and the regression Langmuir Q m was demonstrated to be highly dependent on the aqueous concentration. The regression Q m increased from 0.066 to 2.17 mg·g -1 (by ~3-fold) for the selected soil, and from 2.12 to 48.4 mg·g -1 (by ~23-fold) for the chosen biochar when the highest initial aqueous concentration increased from 2.34 to 887 mg·L -1 . One inappropriate application for comparison of the regression Langmuir Q m as the adsorption capacity is found, i.e., it is difficult to directly compare the regression Q m without neither a saturated isotherm nor considering the experimental conditions. It is also very hard to accurately predict adsorption behavior by the regressed Langmuir model obtained from a partial adsorption isotherm. It is suggested to pay more attention to the difference between the saturated adsorption capacity and the regression Q m value derived from one unsaturated isotherm., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Electrolytic manganese residue (EMR) contains large quantities of manganese (Mn 2+ ) and ammonia nitrogen (NH 4 + -N). Phosphogypsum (PG) contains plenty of phosphate (PO 4 3- ), fluorine (F - ) and some heavy metals. Separate storage of EMR and PG could seriously damage the ecological environment. In this study, synergistic stabilization/solidification (S/S) of EMR and PG was studied. The effects of EMR:PG mass ratio, S/S pH, solid-liquid ratio and temperature on the concentrations of NH 4 + -N, PO 4 3- , Mn 2+ and F - in the leaching solution, and the characteristics of EMR and PG were studied. Meanwhile, the synergistic S/S mechanisms of EMR and PG, and leaching test were investigated. The results showed that the concentrations of F - , PO 4 3- , NH 4 + -N and Mn 2+ in the leaching solution were 4.5 mg/L, 13.6 mg/L, 55.5 mg/L and 0.8 mg/L, respectively, when the mass ratio of EMR to PG was 1:2 and the pH was 9.0 adjusted by MgO after 20 days S/S. Manganese was mainly solidified as Mn 3 (PO 4 ) 2 ·7H 2 O and Mn(OH) 2 , and ammonia nitrogen was mainly stabilized as struvite; fluorine was mainly stabilized as (Mn, Ca, Mg)F 2 , and phosphate was mainly solidified as (Mn, Ca, Mg) 3 (PO 4 ) 2 and (Mn, Ca, Mg)HPO 4 . The leaching test results showed that PO 4 3- and NH 4 + -N were reduced to 13.6 mg/L and 55.5 mg/L, respectively, and the concentrations of all the measured heavy metals and F - were within the permitted level for the GB8978-1996 after 20 days S/S., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Electrolytic metal manganese residue leachate (EMMRL) was produced from long-term deposition of electrolytic metal manganese residue. EMMRL contains huge amount of manganese and ammonia nitrogen which could seriously damage the ecological environment. In this study, a chemical equilibrium model-Visual MINTEQ was used to simultaneously optimize removal of manganese and ammonia nitrogen from EMMRL with chemical precipitation methods. In the laboratory experiment, the effect of different N: P ratios and pH were investigated, and the characterization of the precipitates was characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscope (SEM). The results showed that over 99.9% manganese and 96.2% ammonia nitrogen were simultaneously removed, respectively, when molar ratio of N:P was 1:1.15 at pH 9.5. Moreover, the experimental results corresponded well with the model outputs with respect to ammonia nitrogen and manganese removal. Manganese was mainly removed in the form of MnHPO 4 ·3H 2 O and manganite, and ammonia nitrogen was mainly removed in the form of struvite. Economic evaluation indicated the chemical precipitation methods can be applied in the factory when the price of precipitation was higher than 0.295 $/kg., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Electrolytic manganese residue (EMR) is a solid waste generated in the process of producing electrolytic metal manganese and contains a lot of manganese and ammonia nitrogen. In this study, electrokinetic remediation (EK) of manganese and ammonia nitrogen from EMR were carried out by using pulse electric field (PE) in different agents, and sodium dodecyl benzene sulfonate (SDBS), citric acid (CA) and ethylene diamine tetraacetic acid (EDTA) were used as enhancement agents. The removal behavior of ammonia nitrogen and manganese under direct current field (DC) and PE, and the relationship between manganese fractionation and transport behavior, as well as the energy consumption were investigated. The results demonstrated that the removal efficiency of ammonia nitrogen and manganese using PE were higher than DC. SDBS, EDTA and CA could enhance electroosmosis and electromigration, and the sequence of enhancement agent effects were CA, SDBS, EDTA, distilled water. The highest removal efficiency of manganese and ammonia nitrogen were 94.74% and 88.20%, and the effective removal amount of manganese and ammonia nitrogen was 23.93 and 1.48 mg·wh -1 , when CA and SDBS+CA was used as the enhancement agents, respectively. Moreover, electromigration was the main removal mechanism of manganese and ammonia nitrogen in the EK process., (Copyright © 2019 Elsevier Inc. All rights reserved.)

With the rapid development in kinescope technologies, Cathode Ray Tubes (CRTs) now are almost completely replaced by thinner and lighter flat panel displays, such as liquid crystal displays (LCD), plasma display panels (PDP) and light emitting diode (LED) displays. Waste CRT glass contains many poisonous and harmful substances, especially lead. If it is not properly disposed of, it would pose a serious threat to the environment and human health. This paper reviews the existing waste CRT glass recycling technologies, analyses the obstacles that hinder their industrial application, pinpoints its future directions. This paper also points out the academic conflict in the risk of lead contained CRT glass and proposes a basic rule for waste treatment and disposal: the lower risk principle. The results of this study could help to understand waste CRT glass recycling and guide its future research and development., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Critical water system used for decomposition and debromination of waste printed circuit board (PCBs) has two disadvantages: low value-added oil phase products and halfway debromination at low temperature condition. In this study, critical water-alcohol composite medium was found to be a promising method to surmount these disadvantages. Critical water-ethanol (CWE) and critical water-methanol (CWM) were selected as the composite medium. The temperature of CWE and CWM had a significant effect on the oil phase composition. At low temperature CWE/CWM of 300°C, 4-(1-methylethyl)-phenol with high concentration could be recovered. CWM of 400°C was beneficial to the generation of ether compounds and high level of anisole could be obtained, while 450°C was beneficial to the generation of high level of multi-alkyl substituted phenol derivatives or benzene derivatives such as p-xylene. Br-free oil phase products could be obtained when the temperature of CWE/CWM ≥300°C. Different oil phase products with high level of chemicals or chemical intermediates could be obtained by controlling the reaction conditions of CWE/CWM. It is believed that the additional value of the oil phase products derived from waste PCBs can be greatly improved by this new process., (Copyright © 2017 Elsevier B.V. All rights reserved.)

This study examined simultaneous stabilization and solidification (S/S) of Mn 2+ and NH 4 + -N from electrolytic manganese residue (EMR) using MgO and different phosphate resource. The characteristics of EMR NH 4 + -N and Mn 2+ S/S behavior, S/S mechanisms, leaching test and economic analysis, were investigated. The results show that the S/S efficiency of Mn 2+ and NH 4 + -N could reach 91.58% and 99.98%, respectively, and the pH value is 8.75 when the molar ratio of Mg:P is 3:1 and the dose of PM (MgO and Na 3 PO 4 ·12H 2 O) is 8wt%. In this process, Mn 2+ could mainly be stabilized in the forms of Mn(H 2 PO 4 ) 2 ·2H 2 O, Mn 3 (PO 4 ) 2 ·3H 2 O, Mn(OH) 2 , and MnOOH, and NH 4 + -N in the form of NH 4 MgPO 4 ·6H 2 O. Economic evaluation indicates that using PM process has a lower cost than HPM and HOM process for the S/S of Mn 2+ and NH 4 + -N from EMR at the same stabilization agent dose. Leaching test values of all the measured metals are within the permitted level for the GB8978-1996 test suggested when the dose of PM, HPM and HOM is 8wt%., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Ultrafine cobalt ferrite (CoFe2O4) nanoparticles with narrow size distributions and regular morphologies were prepared through an improved procedure based on the high-temperature diol reduction method. By replacing the original reducing agent like expensive dihydric alcohol, oleylamine was applied as both stabilizer and reducing agent, which benefit for large scale synthesis of magnetic CoFe2O4 nanoparticles. To produce protein-separation agent with both high specific surface area and magnet content, inverse microemulsion system and substitution reaction were employed to render the produced CoFe2O4 nanoparticles with dense silica bilayer and iminodiacetic acid (IDA)-like structure modification. After the chelation with Cu(2+), the metal-immobilized CoFe2O4 nanoparticles can specifically absorb bovine hemoglobin (BHb) with maximum adsorption capacity as qm=1812.3mg/g. Compared with the reported Cu(2+)-immobilized magnetic nanoparticles, the as-prepared CoFe2O4@Si-IDA-Cu(2+) nanoparticles exhibited excellent adsorption capacity and were applied as high efficient protein separation agent in a real complex biological fluid like bovine blood., (Copyright © 2016 Elsevier B.V. All rights reserved.)

The objectives of this study were to track the occurrence, bioaccumulation and sources of phenolic endocrine disrupting chemicals (EDCs) in a representative urban river (Panlong River) of Yunnan-Guizhou Plateau. It provided more comprehensive fundamental data for risk assessment and contamination control of phenolic EDCs in aquatic environments. Phenolic EDCs, such as nonylphenol-di-ethoxylate (NP2EO), nonylphenol-mono-ethoxylate (NP1EO), 4-nonylphenol (4-NP), bisphenol A (BPA), 4-cumylphenol (4-CP) and 4-tert-octylphenol (4-t-OP), were ubiquitously present in Panlong River. The distribution of phenolic EDCs in the water and sediment tended to assume a shape like an inverted letter "W". The residual levels of phenolic EDCs increased dramatically in certain areas. The concentrations of NP2EO, NP1EO, 4-NP, BPA, 4-CP, 4-t-OP and the total phenolic EDCs (ΣPEDCs) were up to 202, 154, 17, 79, 3.3, 4.6 and 429 ng/L in water, and were up to 352, 316, 124, 18, 14, 4.8 and 813 ng/g in sediment, respectively. However, the concentrations of 4-NP, BPA, 4-CP, 4-t-OP and ΣPEDCs in the three predominant fish species (Carassius auratus, Cyprinus carpio and Anabarilius alburnops) were up to 63, 113, 12, 14 and 201 ng/g, respectively. Distribution characteristics of phenolic EDCs in water were significantly similar to those found in sediment, but different in fish. Occurrence, bioaccumulation and sources of phenolic EDCs were mainly subjected to the distribution characteristics of industry, agriculture and residential areas in Panlong catchment. Moreover, the bioconcentration factors (BCFs) were closely related to the octanol-water partition coefficients (log K(ow)) of phenolic EDCs. Without direct input, the redissolution of phenolic EDCs from sediments seems conceivable. The concentrations of phenolic EDCs in the sections of urban areas were remarkably higher than those in suburban sections, since there could exist a potential risk to aquatic organisms and even to human., (Copyright © 2016 Elsevier Inc. All rights reserved.)

In recent years, a potential controversy has arisen that whether the metal speciation in solid matrix determined its electrokinetic (EK) removal efficiency or by contrast. In present study, Cu and Zn in anaerobic digestate were selected as candidates to investigate the relation between the species of metal and EK treatment. The obtained results show that the removal efficiency for each fraction decreased in the order as follows: exchangeable ≥ bound to carbonates > bound to Fe-Mn oxides>bound to organic matters >> residual. For both Cu and Zn, their total removal performance was dependent on their dominant fraction in the digestate. A constant pH maintenance around the digestate via circulation of acid electrolyte is an optional operation because a strong acid atmosphere (pH < 2) around the digestate can be formed automatically as EK time elapses. Despite that many reactions occurred during EK process, the species distribution of Cu and Zn in the digestate determined their total EK removal efficiency essentially., (Copyright © 2014 Elsevier B.V. All rights reserved.)

A novel process for crystalline silicotitanate (CST) synthesis was developed using waste cathode ray tube (CRT) panel glass as silicon source. The key trait of the process was to extract most of the silicon out of the glass for CST preparation, but leave Ba and Sr in the residue which had the potential to be employed as raw material for metallic Ba and Sr metallurgy. In the synthesis process, waste CRT panel glass was firstly treated by supercritical water (SCW)-NaOH solution for Si extraction, then sol-gel and hydrothermal treatments were used for CST preparation. 80% of Si in the glass could be extracted into the solution, while Sr and Ba were enriched in the residue in the form of Sr(2)SiO(4) and Ba(2)Si(3)O(8), respectively. Sr and Ba contents in the residue were 2-3 times higher than those in the raw glass. SEM, XRD and TEM results indicated that CST was successfully synthesized. Ion exchanging experiments showed that the batch distribution coefficient of the synthesized CST to Cs(+) was up to 1.2x10(4) mL/g at pH 0.26., (2010 Elsevier B.V. All rights reserved.)

Incineration of medical waste (MW) is an important alternative way for disposal of this type of hazardous waste, especially in China because of the outbreak of severe acute respiratory syndromes (SARs) in 2003. Thus, far, fly ash has received much attention but less attention has been paid to bottom ash. In this study, bottom ash samples were collected from a typical MW incinerator, and typical pollutants including heavy metals and polycyclic aromatic hydrocarbons (PAHs) in the ash were examined. X-ray fluorescence spectroscopy results indicated that CaO, SiO(2) and Al(2)O(3) were the main components of the bottom ash. Inductively coupled plasma-optical emission spectroscopy showed that the ash contained large amounts of heavy metals, including Zn, Ti, Ba, Cu, Pb, Mn, Cr, Ni and Sn. Most of the heavy metals (e.g., Ba, Cr, Ni, and Sn) presented in the residual fraction; whereas Mn, Pb and Zn presented in Fe-Mn oxides fraction, and Cu in organic-matter fraction. Toxicity characteristic leaching procedure tests indicated that the leached amounts of heavy metals were well below the limits. The sum of 16 US EPA priority PAHs (Sigma PAHs) varied from 10.30 to 38.14 mg kg(-1), and the total amounts of carcinogenic PAHs ranged between 4.09 and 16.95 mg kg(-1), exceeding the limits regulated by several countries. This research provides basic information for the evaluation of the environmental risk of MW incinerator bottom ash.

A novel process for the treatment of hazardous waste Cathode Ray Tube (CRT) glass, based on self-propagating reaction, was proposed. In the process, various types of CRT glass powders were blended with suitable amount of ferric oxide and magnesium, and the mixtures could generate self-propagating reaction once locally ignited by a thermal source. Generally, the self-propagating reaction could be well maintained when the CRT glass content in the mixture was no more than 60 wt.%, and the combustion wave velocity and maximum combustion temperature decreased along with the increase in glass amount. XPS experiments showed that heavy elements in the final products became more stable and were solidified during the process. Leaching tests demonstrated that heavy metals in the final products fulfilled the environmental regulations of USEPA. It is supposed that the detoxified products have the potential of being used as construction materials.

Cathode ray tube (CRT) is the first and foremost problem that must be solved in electronic waste disposal, and the key of which lies in the detoxification and reutilization of lead-contained funnel glass. In this study, a novel and effective process for funnel glass of dismantled CRT treatment was developed. The key point of the process was to recover metallic lead from the funnel glass and to prepare foam glass synchronously. Experimental results showed that lead recovery rate increased first with the increase of temperature, carbon adding amount, and holding time, then reached a plateau value, but pressure was on the contrary. The optimum temperature, pressure, carbon adding amount and holding time for lead recovery were 1000 degrees C, 1000 Pa, 5% and 4h, respectively, and the maximum lead recovery rate was 98.6%. In the pyrovacuum process, lead in the funnel glass was firstly detached and changed to PbO, then reduced and evaporated, and was recovered in the form of pure metal with a purity of 99.3%. The residue porous glass was environmentally acceptable for construction application.