Journal of Environmental Chemical Engineering
·
2022
·
IF 7.968
Runhao Zhang,Miao Gong,Yujie Yan,Jiangya Ma,Huiwen Zhang
In this study, the degradation behaviour of phospholipid 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) during hydrothermal conversion (HC) and the effect of alkali additives on phosphorus forms during HC of phospholipids and different phosphorus-containing wastes were investigated. The mechanism of phosphate-alkali-directed regulation and transformation was discussed and analysed with batch hydrothermal treatment experiments and characterizations such as XRD and SEM. The obtained results showed that DOPC degradation was divided into two periods, i.e., the initial accumulation of phosphorus-containing precursors with increasing temperature, followed by complete degradation to H 3 PO 4 as treatment continued. In addition, compared with the activation of P by NaOH, Ca(OH) 2 is more favourable for the stabilization of P and the migration of non-apatite inorganic phosphorus (NAIP) to apatite inorganic phosphorus (AP). The pH and appropriate feed Ca/P molar ratio during HC determine the degree to which total phosphorus is converted to Ca-bound P. The findings reveal the mechanism of phosphate-alkali-directed regulation and transformation and provide a theoretical reference for the efficient treatment of phosphorus-containing waste and the alkali-directed production of high-phosphorus bioavailability products.
研究领域:
环境科学
·
生物化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CRYSTAL GROWTH
·
2019
·
IF 1.573
Lianlian Zhan,Yang Zhang,Shili Zheng,Ying Zhang,Binqiang Fan,Ping Li,Yi Zhang
Crystallization of ammonium polyvanadate is a key procedure for the production of vanadium pentoxide. The kinetics of nucleation of ammonium polyvanadate and the effects of impurities on the nucleation including sodium ion, potassium ion, hexavalent chromium ion, dihydrogen phosphate were studied in this research by using conductivity method. The solubility of ammonium polyvanadate was determined first, then the nucleation parameters were obtained by combining induction period with the classical primary nucleation theory. The results show the nucleation is homogeneous when with a high supersaturation degree of higher than 25. The critical nucleation radius, free energy and activation energy decrease, and the nucleation rate increases, with the increase of supersaturation degree. The existence of sodium ion, potassium ion, dihydrogen phosphate in the solution will prolong the induction period of crystallizing ammonium polyvanadate, with phosphorus showing the most significant influence. The morphology of the ammonium polyvanadate crystals will change from flake to spherical-like with the existence of phosphorus.
研究领域:
化学工程
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2018
·
IF 6.735
Yao Xu,Fei-er Han,Da-peng Li,Jing Zhou,Yong Huang
The transformation of sedimentary phosphorus (P) fractions by point injection of CaO 2 was investigated in this study. The results showed that the addition of CaO 2 increased the dissolved oxygen (DO) in the overlying water as well as its pH. Simultaneously, the concentrations of total organic carbon (TOC), ammonia nitrogen (NH 4 + -N), total phosphorus (TP) and dissolved inorganic P (DIP) in the overlying water were sharply reduced by the point injection of CaO 2 , indicating that this accelerated the mineralisation rate of organic matter. It also favoured the formation and maintenance of the micro-oxidation environment in the deep sediments. NH 4 Cl-P, Fe/Al-P and Ca-P increased significantly, while the Res-P decreased sharply, especially close to the injection point of CaO 2 , accelerating the transformation of P. These results can all be attributed to the oxidation of organic P and the adsorption of dissolved P from the overlying water. Additionally, the NaHCO 3 -extractable phosphorus (Olsen-P) and algal available phosphorus (AAP) were reduced, and their percentages in Ca-P and Fe/Al-P also decreased, especially close to the injection point of CaO 2 . The bioavailable P decreased from 25.6% (the initial) to 17.2% (the mean for the different distances) after the point injection of CaO 2 , when the sum of the Olsen-P and AAP was used to calculate the bioavailable P. This indicates that point injection of CaO 2 favours not only the transformation of P species but also inhibition of the bioavailable P. This is attributable to acceleration of the transformation from bioavailable to inert P.
研究领域:
环境科学
·
生态学
✓ 已验证
产品关联
DOI
高影响因子
BIORESOURCE TECHNOLOGY
·
2020
·
IF 7.539
Zhipeng Zhang,Qian Ping,Dan Gao,Peter A. Vanrolleghem,Yongmei Li
Five ferric-phosphate (Fe(III)Ps) with amorphous or crystalline structures were added to waste activated sludge (WAS) for anaerobic fermentation, aiming to investigate effects of Fe(III)Ps forms on phosphorus (P) release and the performance of WAS fermentation. The results revealed that the Fe(III) reduction rate of hexagonal-FePO 4 was faster than that of monoclinic-FePO 4 ·2H 2 O, thanks to its lower crystal field stabilization energy. FePO 4 ·nH 2 O was reduced to vivianite and part of the phosphate was released as orthophosphate (PO 4 -P). Giniite (Fe 5 (PO 4 ) 4 (OH) 3 ·2H 2 O) as an iron hydroxyphosphate was transformed to β Fe(III)Fe(II)(PO 4 )O-like compounds without PO 4 -P release. In addition, Fe(III)Ps had an adverse effect on the anaerobic fermentation of WAS. The specific hydrolysis rate constant and volatile fatty acids (VFAs) yield decreased by 38.4% and 41.9%, respectively, for the sludge sample with amorphous-FePO 4 ·3H 2 O, which dropped the most. This study provides new insights into various forms of Fe(III)Ps performance during anaerobic fermentation and is beneficial to enhancing P recovery efficiency.
研究领域:
环境工程
·
废物管理
·
水处理
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）