Journal of Biobased Materials and Bioenergy
·
2019
·Vol. 13
·期 4
·523-531
·
IF 0
Yao Shuangquan,Liu Baojie,Nie Shuangxi,Wang Shiwei,Qin Chengrong,Wang Shuangfei
Adsorbable organic halogen (AOX) is mainly produced by the reaction of residual lignin and chlorinated bleaching agents during bleaching processes. The formation of AOX can be reduced via optimization, addition of chemical additives, and/or pretreatment processes. Only a few studies
exist on the effective purification of chlorine dioxide solutions and its effect on AOX reduction. In this paper, the effects of the extraction pressure, temperature, pH, and extraction time on the chlorine gas removal rate (CR) were evaluated. In addition, a response surface model was established
to optimize the chlorine gas removal. The temperature of chlorine gas separation was optimized at 39.85 °C, with a separation pressure of –51.20 kPa and solution pH of 1.94, providing an estimated CR of 70.93% under the optimum separation conditions. Chlorine dioxide solutions with
and without chlorine gas removal were used for pulp bleaching. AOX formation was reduced by 69.57% at the same 2.0% chlorine dioxide dosage, while the pulp brightness decreased by 3.0%ISO. In addition, AOX formation was reduced by 27.90% at the same bleached pulp brightness (80.00%ISO). The
results provide theoretical support for the production of high-purity chlorine dioxide solutions and the development of clean pulping and papermaking processes.
研究领域:
制浆造纸工程
·
环境科学
✓ 已验证
DOI
CHEMOSPHERE
·
2022
·
IF 8.943
Fei Yang,Xinbo Zhang,Zixuan Zhao,Wenshan Guo,Huu Hao Ngo
The transformation of halogenated organics in advanced oxidation processes (AOPs) has been extensively investigated. However, we currently know little about the fate of halogenated pollutants in the presence of exogenic halides (Cl − or Br − ). Herein, the degradability , mineralization rate, and accumulation capacity of adsorbable organic halogen (AOX) for chlorophenols (2-chlorophenol (2-CP), 3-chlorophenol (3-CP), 4-chlorophenol (4-CP), and 2,4,6-trichlorophenol (TCP)) were compared in the Fe 2+ /persulfate (PS) process with the addition of exogenic halides. Results indicate that exogenic X − can lead to a decrease in chlorophenols degradation and mineralization rate, undesirable accumulation of AOX, and generation of halogenated by-products which are more toxic than precursor chlorophenols. Results of kinetics modeling show that Cl 2 •- plays more important role than SO 4 •- with an addition of Cl − , while SO 4 •- , Br 2 •- , and Br 2 are responsible for the effect of Br − . As well, the effect of endogenic chlorine atoms on chlorophenols reveals that the degradability and AOX formation potential of 3-CP are highest while that of TCP are the lowest. This study demonstrates the significant influence of endogenic chlorine atoms and exogenic X − on the fate of typical organic halogen compounds. Consequently, the X − level and position/number of halogen atoms should be considered simultaneously when treating organohalogen compounds .
研究领域:
环境科学
·
化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
WATER RESEARCH
·
2018
·
IF 7.051
Yinan Bu,Mingrui Song,Jiarui Han,Zhenxuan Zhang,Baiyang Chen,Xiangru Zhang,Mengting Yang
Adsorbable organic halogen (AOX) is a parameter conventionally used to indicate the sum of organic halogenated disinfection byproducts (DBPs), which are formed from the reactions of disinfectants with dissolved organic matter , bromide and iodide in water. To overcome the issues of the AOX analytical method, we proposed a new facile and green pretreatment method to enable the analysis of nonionic total organic halogen (NTOX) via the following three steps: 1) separation of NTOX and halides with electrodialysis , 2) conversion of NTOX with ultraviolet (UV) photolysis, and 3) analysis of halides with ion chromatography . To verify this proposal, we mainly evaluated the efficiency of vacuum ultraviolet (VUV) coupled with UV photolysis (VUV−UV) in converting NTOX into halides. Results showed that by applying VUV irradiation for 60 min and UV irradiation at pH 10–11 for another 30 min, over 85.5% of each halide from 20 representative small molecular weight DBPs (each at 100 μg-X/L level) was recovered. The purpose of UV photolysis under alkaline conditions was to reduce oxyhalides (such as bromate and iodate) formed in the VUV process back to halides. With the aid of electrospray ionization-triple quadrupole mass spectrometry, we captured the whole pictures of high molecular weight polar DBPs in a chlorinated drinking water before and after VUV−UV, through which averagely 96.4% of dehalogenation with the VUV−UV treatment was observed. An illustrative comparison of the conventional AOX method and the proposed NTOX method indicates that although the detected NTOX was lower (by 2.3–30.6%) than AOX, the results of the two methods were highly correlated (R 2 > 0.97). All these hence verified the photolysis as a mature yet novel tool for sample pretreatment in environmental analytical chemistry.
研究领域:
环境科学
·
分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Royal Society Open Science
·
2019
·Vol. 6
·期 10
·
IF 2.515
Lisheng Shi,Jiayan Ge,Fuqiang Zhang,Shuangxi Nie,Chengrong Qin,Shuangquan Yao
Adsorbable organic halogen (AOX) is generally formed by the reaction of residual lignin in pulps with chlorine dioxide during bleaching. Lignin has a complex structure. Different functional groups and bonds are present in lignin structures. Phenolic hydroxyl is one of the important functional groups in lignin, and it significantly influences the chemical properties and reactivity. To study the effect of phenolic hydroxyl on AOX formation, vanillyl alcohol (VA) was selected as the phenolic lignin model compound, and veratryl alcohol (VE) was selected as the non-phenolic lignin model compound in this study. The kinetics of AOX formation by the reaction of VA or VE with chlorine dioxide was studied. The effects of pH, chlorine dioxide, lignin model compound concentration and reaction temperature on AOX formation are discussed. The activation energies of the reaction of VA and VE with chlorine dioxide are 16 242.47 J mol−1 and 281.34 J mol−1, respectively. Thus, we found that the non-phenolic lignin can react with chlorine dioxide to form AOX more easily than phenolic lignin.
研究领域:
林产化学与技术
·
环境科学
✓ 已验证
DOI
PubMed
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2020
·
IF 5.774
Min Lei,Qian Gao,Kemeng Zhou,Parikshit Gogoi,Jing Liu,Jiabao Wang,Hainong Song,Shuangfei Wang,Xinliang Liu
Adsorbable organic halogens (AOX) are used as a parameter to determine the total amount of organic halogens in the environment. 4-chlorophenol (4-CP), as a type of AOX, can persist in the environment for a long time and is not biodegradable. 4-CP has significant carcinogenic and teratogenic effects on humans and animals. In this study, a catalytic system employing phosphomolybdic acid (PMA) and hydrogen peroxide (H 2 O 2 ) was developed for degrading 4-CP. The degradation and the mechanisms of 4-chlorophenol (4-CP) as an AOX simulant was investigated. The removal efficiency of 4-CP, the AOX content, and total organic carbon were used to evaluate its molecular structure. The results show that 4-CP was fully converted, 19.81% to other species of AOX and 44.52% to CO 2 and H 2 O. Moreover, the intermediates were detected and analyzed, and the possible pathways of 4-CP degradation were drawn. 4-CP attached to PMA, there by leading to ring-opening or dichlorination, and the generation of some other chemical species, such as phenol , benzoquinone, cyclohexanone, 4-chlorohexa-2,4-dien-1-ol, and 3-chlorohexa-2,4-diene-1,6-diol. These species would then be mineralized under the effects of free radicals. PMA can promote the formation of free radicals and shows exceptional efficiency in the degradation of 4-CP.
研究领域:
环境化学
·
催化
·
水处理
·
污染物降解
✓ 已验证
产品关联
DOI
高影响因子
Journal of Environmental Sciences
·
2022
·
IF 6.796
Zhenxing Yao,Mingquan Wang,Ruibao Jia,Qinghua Zhao,Li Liu,Shaohua Sun
This study examined the effectiveness for degradation of hydrophobic (HPO), transphilic (TPI) and hydrophilic (HPI) fractions of natural organic matter (NOM) during UV/H 2 O 2 , UV/TiO 2 and UV/K 2 S 2 O 8 (UV/PS) advanced oxidation processes (AOPs). The changing characteristics of NOM were evaluated by dissolved organic carbon (DOC), the specific UV absorbance (SUVA), trihalomethanes formation potential (THMFP), organic halogen adsorbable on activated carbon formation potential (AOXFP) and parallel factor analysis of excitation–emission matrices (PARAFAC-EEMs). In the three UV-based AOPs, HPI fraction with low molecular weight and aromaticity was more likely to degradate than HPO and TPI, and the removal efficiency of SUVA for HPO was much higher than TPI and HPI fraction. In terms of the specific THMFP of HPO, TPI and HPI, a reduction was achieved in the UV/H 2 O 2 process, and the higest removal rate even reached to 83%. UV/TiO 2 and UV/PS processes can only decrease the specific THMFP of HPI. The specific AOXFP of HPO, TPI and HPI fractions were all able to be degraded by the three UV-based AOPs, and HPO content is more susceptible to decompose than TPI and HPI content. UV/H 2 O 2 was found to be the most effective treatment for the removal of THMFP and AOXFP under given conditions. C1 (microbial or marine derived humic-like substances), C2 (terrestrially derived humic-like substances) and C3 (tryptophan-like proteins) fluorescent components of HPO fraction were fairly labile across the UV-based AOPs treatment. C3 of each fraction of NOM was the most resistant to degrade upon the UV-based AOPs. Results from this study may provide the prediction about the consequence of UV-based AOPs for the degradation of different fractions of NOM with varied characteristics.
研究领域:
环境科学
·
水处理工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Royal Society Open Science
·
2019
·Vol. 6
·期 2
·
IF 2.515
Lisheng Shi,Jiayan Ge,Shuangxi Nie,Chengrong Qin,Shuangquan Yao
Adsorbable organic halogens (AOX) are formed in pulp bleaching as a result of the reaction of residual lignin with chlorine dioxide. The natural structure of lignin is very complex and it tends to be damaged by various extraction methods. All the factors can affect the study about the mechanism of AOX formation in the reaction of lignin with chlorine dioxide. Lignin model compounds, with certain structures, can be used to study the role of different lignin structures on AOX formation. The effect of lignin structure on AOX formation was determined by reacting phenolic and non-phenolic lignin model compound with a chlorine dioxide solution. Vanillyl alcohol (VA) and veratryl alcohol (VE) were selected for the phenolic and non-phenolic lignin model compound, respectively. The pattern consumption of lignin model compounds suggests that both VA and VE began reacting with chlorine dioxide within 10 min and then gradually steadied. The volume of AOX produced by VE was significantly higher than that produced by VA for a given initial lignin model compound concentration. In a solution containing a combination of VA and VE in chlorine dioxide, VE was the dominant producer of AOX. This result indicates that the non-phenolic lignin structure was more easily chlorinated, while the phenolic lignin structure was mainly oxidized. In addition, AOX content produced in the combined experiments exceeded the total content of the two separate experiments. It suggested that the combination of phenolic and non-phenolic lignin structure can promote AOX formation.
研究领域:
制浆造纸科学
·
环境化学
·
有机化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
INDUSTRIAL CROPS AND PRODUCTS
·
2025
·
IF 6.2
Jinwei Zhao,Cheng Xu,Jiali Pu,Yi Xie,Haodong Guo,Baojie Liu,Chengrong Qin,Shuangquan Yao,Chen Liang
Bamboo is a fast-growing, high-biomass, and mechanically strong renewable resource. It shows great potential in cellulose-based materials and bio-based products. However, its complex tissue structure and unique lignin distribution limit the efficiency and applicability of conventional delignification processes. In this study, a synergistic lignin removal strategy combining high-proportion chlorine dioxide (ClO 2 ) pretreatment with oxygen delignification was developed. Two process sequences, O-D PI and D PI -O, were systematically compared in terms of reaction mechanisms during bamboo fiber lignin removal. Results showed that, in the D PI -O process, ClO 2 preferentially oxidized lignin to form quinone-type intermediates. These intermediates were then effectively degraded in the subsequent oxygen delignification stage. This led to a significantly higher lignin removal rate (84.90 %) and a notable reduction in kappa number (2.49) and AOX generation (0.267 kg/t pulp). Multidimensional characterization using 2D HSQC NMR and 31 P NMR confirmed more complete cleavage of S/G units and β-O-4 linkages in the D PI -O system. The carboxyl group content of residual lignin increased significantly to 1.194 mmol/g, revealing the critical role of quinone intermediates in deep oxidative degradation. Kinetic studies further showed that the lignin removal rate was highly sensitive to alkali concentration (a 1 = 0.6012), especially under low oxygen pressure. In low-alkali environments, oxygen pressure became more influential (b 1 = 0.1382). This study elucidates the reaction pathway and key controlling parameters of oxygen-assisted, high-proportion ClO 2 delignification. It provides both theoretical and practical support for efficient lignin degradation and high-purity cellulose fiber production.
研究领域:
木材化学
·
制浆造纸技术
·
生物炼制
·
化学工程
·
可持续材料
✓ 已验证
产品关联
DOI
高影响因子
Water
·
2025
·Vol. 17
·期 17
·2563
·
IF 3
Chao Feng,Tongyu Liu,Yongping Shi,Jimin Shen,Lei Yuan,Yuanqing Guo
The interaction of disinfectants with bromide/iodide ions and natural organic matter (NOM) generates brominated/iodinated disinfection byproducts (Br/I-DBPs), known for their heightened cytotoxicity and genotoxicity relative to chlorinated DBPs. This study investigated Br/I-DBP formation during sodium hypochlorite (NaClO) disinfection of lignin-containing synthetic water by quantifying adsorbable organic halogens (AOX) and trihalomethanes (THMs). Disinfection of bromide-containing water yielded a bromide ion (Br−) to adsorbable organic bromine (AOBr) conversion rate of approximately 60%, with bromine within THMs accounting for about 30% of the total AOBr, indicating significant brominated DBP formation where THMs represent a major fraction. Conversely, iodide ion (I−) conversion to adsorbable organic iodine (AOI) is minimal, suggesting negligible iodinated DBP formation under NaClO disinfection. Examination of key parameters revealed that brominated THM (Br-THM) formation decreased with increasing lignin concentration, while iodinated THM (I-THM) formation increased. The effect of chlorine dose differed: Br-THM formation exhibited an initial increase followed by a decrease at higher doses, whereas I-THM formation consistently decreased. Both Br-THM and I-THM formation increased with higher bromide or iodide ion concentration and with increasing pH. These results highlight the distinct pathways and influencing factors governing brominated versus iodinated DBP formation in lignin-containing waters disinfected with hypochlorite.
研究领域:
环境科学
·
水处理
·
消毒副产物
·
毒理学
·
天然有机物化学
✓ 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）