CHINESE JOURNAL OF CHEMICAL ENGINEERING
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2025
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IF 3.7
Huagui Jin,Xuebin An,Shizhao Wang,Yunshan Wang,Gang Yang,Yong Sun
s This study investigates the removal of fluorine (F) impurities from phosphogypsum (PG) using steam as the reaction medium. The effects of the reaction atmosphere, temperature, time, and steam velocity on F impurities removal were systematically examined. The results showed that with a steam velocity of 0.0184 m·s −1 , a reaction temperature of 700 °C, and a reaction time of 60 min, the F removal rate reached 95.87%. Further investigations into the defluorination mechanism revealed that steam and SiO 2 synergistically enhance fluoride removal, playing a crucial role in improving the defluorination efficiency. Kinetic analysis of the defluorination process, based on the shrinking core model (SCM), indicated that internal diffusion is the rate-controlling step, with the activation energy of 30.12 kJ·mol −1 . This study identifies optimal conditions for PG defluorination and proposes a defluorination mechanism, contributing to the theoretical understanding of impurity removal through the thermal treatment of PG.
研究领域:
化学工程
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环境科学
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DOI
高影响因子
ACS Omega
·
2024
·
IF 3.7
Yuqian Zhou,Yuhe Zhou,Renlong Liu,Guocan Zheng,Changyuan Tao,Benjun Xi
The resource utilization of phosphogypsum (PG) is the key to promote the green development of the phosphorus chemical industry. The natural environment and public safety are significantly threatened by the enormous volume of PG storage. In this study, Ca and S were successfully recovered from the PG via a multistep precipitation in the NaOH–BaCO3 system. The alkali solution can be recycled five times, with a first recovery ratio of about 97.9%, and the decomposition ratio of PG remained above 70% after five cycles. In addition, the recovery ratios of Ca and S in PG are 99.9 and 82.5%, respectively. The product of BaSO4 can be used as a weighting agent for oil and natural gas drilling mud. The BaSO4 can also be used as wave-absorbing materials, and its reflection loss value reaches 97.8% of the analytical purity BaSO4. This work provides a new idea for the efficient recycling of Ca and S in PG with an outstanding application prospect.
研究领域:
化学工程
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环境科学
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DOI
PubMed
高影响因子
RESOURCES CONSERVATION AND RECYCLING
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2024
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IF 11.2
Hong Yu,Long Liu,Mingxia Liu,Hanquan Zhang,Run Mao
Red mud (RM) and phosphogypsum (PG) are both large-scale industrial solid wastes, which cause waste of resources reserved in them and pose a huge threat to the environment if not treated appropriately. Guide by the concept of “waste control by waste”, the individual and cooperated effect of PG and sodium sulfate (Na 2 SO 4 ) on iron recovering from RM through reductive roasting-magnetic separation process was comparably investigated. Systematical factorial tests verified the advantage of binary additive. An iron concentrate with iron grade and recovery of 89.02 % and 87.46 % was obtained under the optimized conditions. Mechanistic studies demonstrated that iron oxides were converted to metallic iron through reductive roasting, along with which PG was beneficial for the releasing of iron from complex iron-hosting minerals to a certain extent while binary additive was even more efficient for the reducing, decomposing and grain growing processes. This work realizes the simultaneous utilization of both waste resources.
研究领域:
环境科学
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冶金工程
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DOI
高影响因子
Journal of Building Engineering
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2024
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IF 6.7
Zhi Li,Shengjie Yao,Guichao Wang,Chuangang Fan,Xiaoxu Wu
This study investigates the effects of various components on the performance of aerogel-phosphogypsum (APG) thermal insulation mortar. This study investigates the effects of various components on the performance of aerogel-phosphogypsum (APG) thermal insulation mortar, with a special focus on optimizing the composition to enhance mechanical properties. The parametric range explored included phosphogypsum content from 10 to 30 wt%, hollow glass microspheres (HGS) from 5 to 15 wt%, and aerogel slurry from 40 to 80 wt%. Our findings reveal that the optimal composition, which provided the best balance between thermal insulation and mechanical strength, consisted of 20 wt% phosphogypsum, 10 wt% HGS, and 60 wt% aerogel slurry. Notably, the introduction of 0.14 % hydroxypropyl methylcellulose (HPMC) and 1.89 % re-dispersible polymer powder (RPP) significantly enhanced the compressive strength of the mortars. Specifically, compressive strength increased from an initial 0.05 MPa–0.27 MPa post-enhancement with HPMC and RPP. This research provides a detailed understanding of how individual components influence the formulation of APG and offers insights for optimizing the overall performance of aerogel-phosphogypsum composites, contributing to advancements in sustainable building materials.
研究领域:
建筑材料
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可持续发展
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材料科学
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DOI
高影响因子
JOURNAL OF POLYMER RESEARCH
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2022
·Vol. 29
·期 11
·1-11
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IF 3.061
Zhang Jie,Lu Han,Zeng Dan,Meng Dongye,Chen Jiajun,Liu Kun,Ran Jingyu,Su Xiangdong
Phosphogypsum is industrial waste that wastes a lot of land and pollutes the environment. In recent years, the application of phosphogypsum in polymers has become one of the research hotspots. In this paper, phosphogypsum/polystyrene composite was prepared by pretreatment, organic modification, and then mixed with polystyrene solution. It was found that phosphogypsum crystals had a highly orientation arrangement after pre treatment. Phosphogypsum exists as single crystal in polystyrene. Phosphogypsum has good dispersion and good interfacial properties in the polymerization. It provides guidance and reference for the application of phosphogypsum in polymer.
研究领域:
材料科学
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环境科学
✓ 已验证
DOI
高影响因子
PROCESS SAFETY AND ENVIRONMENTAL PROTECTION
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2024
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IF 6.9
Li Chao,An Xuebin,Jing Hu,Yixiao Wang,Shizhao Wang,Yunshan Wang,Gang Yang,Yong Sun
s This paper reports an enhanced approach of thermal reduction of phosphogypsum (PG) in the presence of sodium chloride (NaCl) in its molten phase. The thermodynamic together with in-situ thermogravimetric-Fourier transform infrared spectroscopy (TG-FTIR) result indicates the yield of CaS (solid) at the investigated temperature range (800–850 °C). Addition of NaCl not only appreciably reduces the activation energy of this reaction (800–850 °C) on average from 315 to 175 (kJ·mol −1 ) materially, but also significantly improve the conversion from CaSO 4 to CaS. Additionally, the NaCl based waste salt (NaCl-WS) containing organic compounds (0.21 wt%) was found to produce similar results when compared with the pure NaCl addition at investigated temperature range. The optimal conditions via parametric optimization: i.e., 800–850 °C, 15 wt% (NaCl-WS), and 6 (ratio of PG/C (carbon) wt/wt), were determined. The mechanistic study together with using density functional theories (DFT) shows that the synergistic effect by NaCl addition was caused by the coupled-vacancy diffusion mechanism when NaCl melts at high temperature and C atom shows proximity to oxygen (O) atom from the SO 4 2- cluster in the CaSO 4 crystallite structure. The evaluation of the process shows appealing advantages over the conventional PG thermal reduction. By carefully manipulating temperature range together with the NaCl-WS addition, the proposed new process simultaneously realizes PG thermal reduction and environmental utilization of NaCl-WS.
研究领域:
化学工程
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环境科学
✓ 已验证
DOI
高影响因子
LANGMUIR
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2025
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IF 3.9
Shengzong Lan,Liuyang Dong,Peilun Shen,Haoran Su,Zhengchang Shen,Dianwen Liu
The accumulation of phosphogypsum (PG) in the phosphorus chemical industry poses significant environmental challenges. Therefore, developing a harmless utilization method is crucial for alleviating these burdens and promoting sustainable industry practices. In this study, PG was used as a flotation inhibitor, enabling the flotation separation of apatite and dolomite based on the main components and dissolution behavior of PG. A microflotation study revealed that 0.875 g/L PG selectively inhibited dolomite when the sodium oleate (NaOL) concentration was 1.5 × 10–4 mol/L, reducing dolomite recovery 76% to 10% at pH in the range of 7–11. Conversely, apatite recovery remained above 90% at pH 7–9 and was only slightly inhibited at pH in the range of pH 9–11. When CaSO4·2H2O and CaHPO4·2H2O were added as flotation inhibitors, they also inhibited dolomite, though their effects were weaker than PG. Measurements of contact angles, zeta potentials, and adsorption capacities indicated that PG enhanced the hydrophilicity of dolomite, hindering NaOL adsorption thereon, while it had little effect on the floatability of apatite. Atomic force and scanning electron microscopy revealed selective PG was adsorbed on the dolomite surface, altering its properties, while PG was weakly adsorbed on the apatite surface and had minimal impact on its properties. The solution chemical composition and microthermal results showed that CaSO4 and CaHPO4 are the effective components of PG inhibition. X-ray photoelectron spectroscopy and time-of-flight secondary ion mass spectrometry confirmed that CaSO4 and CaHPO4 in PG were selectively adsorbed at Ca and Mg ion sites on the dolomite surface. Molecular dynamics simulations showed that CaSO4 interacts with the surface of dolomite, and CaHPO4 can promote the adsorption of CaSO4 on the surface of dolomite. Utilizing PG as a flotation inhibitor provides a novel approach for the environmentally safe use of PG resources.
研究领域:
矿物加工工程
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环境科学
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产品关联
DOI
PubMed
高影响因子
ACS Omega
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2024
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IF 3.7
Yuanxia Li,Fangfang Zeng,Guang Yang,Yi Li,Shun Zhang,Qibin Liu
Phosphogypsum (PG) constitutes a form of solid byproduct emanating from the manufacturing process of wet-process phosphoric acid. The fabrication of one metric ton of wet-process phosphoric acid entails the generation of approximately five tons of phosphogypsum, a highly prolific and economically viable waste stream. If we can effectively solve the problem of poor hydrophobicity of phosphogypsum, it is possible to replace cement and other traditional cementitious materials. In this way, we can not only improve the utilization rate of phosphogypsum but also obtain significant economic and environmental benefits. In the present investigation, hydrophobic surface coatings were synthesized and applied onto the surface of α-hemihydrate phosphogypsum (α-HPG) utilizing sol–gel processing and impregnation techniques. After hydroxylating α-HPG with alkaline solution (OH-α-HPG), titanium dioxide nanoparticles (TiO2) hybridized with perfluorodecyltriethoxysilane (PFDTS) were grafted on its surface. The assessment of the hydrophobic properties of the coatings was conducted through water contact angle measurements, Fourier transform infrared (FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy (SEM) analyses. The contact angle remained above 124.2° after strong acidic and alkaline immersion and 50 tape adhesion experiments with good chemical stability and durability, and the mechanism of surface hydrophobicity modification was discussed. The experimental outcomes demonstrated a notable increase in the hydroxyl group concentration on the α-HPG surface following hydroxylation, significantly enhancing the attachment rate of PFDTS and TiO2 onto the HPG surface. PFDTS and TiO2 can undergo chemical interaction with hydroxyl groups, facilitating their robust adsorption onto the surface of OH-α-HPG through chemisorption mechanisms. After bonding the OH-α-HPG surface with PFDTS and TiO2 via hydrogen bonding, the otherwise hydrophilic α-HPG surface acquired excellent hydrophobicity (OH-α-HPG-PT, contact angle (CA) = 146.7°). The surface modification of α-HPG through hydroxylation and hydrophobicity enhancement significantly augmented the compatibility and interfacial interplay between α-HPG and PT. This research successfully enhanced the hydrophobic properties of α-HPG, profoundly showcasing its immense potential within the construction industry and the realm of comprehensive solid waste utilization.
研究领域:
材料科学
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环境工程
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2024
·
IF 5.8
Zhiqi Zhang,Zhong Tao,Yi Zhang,Lei Wu,Zhiman Zhao,Haixiang Xu
Phosphogypsum (PG), a solid waste produced from the wet process of phosphoric acid production, primarily contains impurities such as phosphates. Understanding how phosphates exist is crucial for the purification and resource utilization of PG. This study employs Energy Dispersive X-ray Spectroscopy (EDS), Fourier Transform Infrared Spectrometer (FTIR), X-ray diffraction (XRD), and Density Functional Theory (DFT) simulations to investigate the forms of phosphates within the CaSO 4 · 2 H 2 O lattice. The research findings reveal that the density of phosphorus (P) increases in regions where the density of sulfur (S) decreases. Higher phosphorus doping enhances the interplanar spacing and unit cell volume of CaSO 4 · 2 H 2 O crystals. Upon comparison, it is evident that the energy required for HPO 4 2- substitution of SO 4 2- is the lowest, suggesting that phosphates are most likely to enter the CaSO 4 · 2 H 2 O lattice in the form of HPO 4 2- . Furthermore, HPO 4 2- substitution in CaSO 4 · 2 H 2 O is likely localized, with no inclination towards intralayer substitution. In instances where phosphate replaces SO 4 2- , the electronic distribution near phosphorus atoms mirrors that of sulfur atoms. This study provides a comprehensive, atomic-level elucidation of the presence of phosphates in gypsum, significantly contributing to the rational utilization of solid waste.
研究领域:
材料科学
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化学工程
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环境科学
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产品关联
DOI
高影响因子
Minerals
·
2022
·Vol. 12
·期 7
·858
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IF 2.818
Yanming Liu,Han Zhang,Dunquan Xiao,Hanjun Wu,Zhenyue Zhang,Lulu Xu,Qingrong Cheng,Hong Zhou,Junxia Yu,Zhiquan Pan,Dongsheng Wang
In this work, ternary and quaternary layered double oxides (PTB-LDO3 and PTB-LDO4) based on phosphate tailings were synthesized by the coprecipitation method. The as-prepared samples were characterized and applied to remove fluorine ions from a phosphogypsum leaching solution. The results indicated that both the precursor of PTB-LDO3 and PTB-LDO4 showed a layered structure with characteristic diffraction peaks of hydrotalcite. Compared with PTB-LDO4, PTB-LDO3 exhibited better adsorption performance at pH 5–6 and a dosage of 0.04 mg L−1. The adsorption kinetics results revealed that the adsorption of fluorine by PTB-LDO3 and PTB-LDO4 reached the adsorption equilibrium in about 3 h, and followed the pseudo-second-order model. The adsorption data could be fitted better with the Langmuir isotherm with the maximum adsorption amounts of 26.03 mg g−1and 15.66 mg g−1for PTB-LDO3 and PTB-LDO4, respectively. The adsorption of fluorine by PTB-LDO3 and PTB-LDO4 were both spontaneous and exothermic, and exhibited excellent reusability and stability. This study provides a possibility for the combined treatment of phosphorus chemical solid waste (phosphorus tailings) and phosphorus chemical wastewater (phosphogypsum leaching liquid).Keywords:phosphate tailings;layered double oxides;adsorption;phosphogypsum leaching solution
研究领域:
环境科学
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材料科学
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DOI
高影响因子
MOLECULES
·
2024
·Vol. 29
·期 11
·2665
·
IF 4.2
Gangan Wang,Chaoyi Chen,Junqi Li,Yuanpei Lan,Xin Lin,Jiahang Chen
The discharge of lead and cadmium wastewater, along with the pollution caused by phosphogypsum, represents a particularly urgent environmental issue. This study employed a straightforward hydrothermal method to convert phosphogypsum into porous calcium silicate hydrate (P-CSH), which was then used to remove and recover Pb(II) and Cd(II) from wastewater. The adsorption capacities of P-CSH for Pb(II) and Cd(II) were notably high at 989.3 mg/g and 290.3 mg/g, respectively. The adsorption processes adhered to the pseudo-second-order kinetics model and the Langmuir isotherm model. Due to identical adsorption sites on P-CSH for both Pb(II) and Cd(II), competitive interaction occurred when both ions were present simultaneously. Additionally, the adsorption efficacy was minimally impacted by the presence of common coexisting cations in wastewater. The dominant mechanisms for removing Pb(II) and Cd(II) via P-CSH were chemical precipitation and surface complexation. Moreover, the adsorbed heavy metals were efficiently separated and reclaimed from the wastewater through a stepwise desorption process. The primary components of the residue from stepwise desorption were quartz and amorphous SiO2. Following dissolution via pressurized alkaline leaching, this residue could be recycled for synthesizing P-CSH. This research offered a new strategy for the resourceful use of phosphogypsum and heavy metal wastewater.
研究领域:
环境科学
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材料科学
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化学工程
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产品关联
DOI
PubMed
高影响因子
CONSTRUCTION AND BUILDING MATERIALS
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2024
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IF 7.4
Baolin Xia,Ruohan Shi,Wei Wang,Weijun Peng,Yijun Cao,Yukun Huang,Guixia Fan
A substantial stockpile of phosphogypsum (PG) not just consumes land resources, but also poses environmental contamination risks. Herein, the conversion of PG into high-value α-hemihydrate gypsum (α-HH) whisker by the atmospheric pressure salt solution method with simple process, high efficiency and low energy consumption was investigated. Sodium nitrate was found to accelerate the conversion of PG into α-HH, and sorbitol could modify the α-HH into rod-like morphology with high aspect ratios . The α-HH whiskers with an average length of 96.28 µm and an average aspect ratio of 25.47 were prepared within 1.5 h under the optimal parameters of 80 ℃, sodium nitrate-30 wt%, PG-12 wt%, and sorbitol-1 wt%. The modulation mechanism was that hydroxyl groups in sorbitol formed strong hydrogen bonds with the sulfate groups on the lateral of the crystals, which promoted the growth of α-HH along the c-axis. Moreover, the filtrate could be effectively recycled by adding salt medium and crystallization modifier. Such technique provides a theoretical basis for the high-value utilization of PG.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）