共查询到19条相似文献,搜索用时 93 毫秒
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利用反应体系中产生的强氧化性自由基,可使水体中有机物污染物分解成小分子物质,基于硫酸自由基(SO4.-)的氧化可降解有机污染物。本文采用化学手段对模拟废水中的有机污染物(主要是聚丙烯酰胺)进行降解,研究亚铁盐及加过硫酸盐与亚铁盐复配的降解效果,考察反应时间、pH值、搅拌对降解效果的影响。结果表明:FeSO4和Na2S2O8复配降解HPAM去除率最高为42.22%,HPAM的去除起主导作用的为硫酸自由基的生成;反应条件中,搅拌条件有利于反应,HPAM去除效果最佳反应时间是2~3 h,pH值为3。 相似文献
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采用光催化合成法,以丙烯酰胺(AM)和二甲基二烯丙基氯化铵(DMDAAC)为单体,以过硫酸钾为光引发剂,在紫外光照射下合成阳离子聚丙烯酰胺(CPAM)。红外光谱分析产物结构证实了该方法的可行性。通过正交试验研究优化反应条件。控制反应条件,制得的阳离子聚丙烯酰胺的特性黏数最大可达到1.31×10^3mL/g,固含量为21.9%,阳离子度为18.0%。 相似文献
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紫外分光光度法测定聚丙烯酰胺中丙烯酰胺的残留量 总被引:3,自引:0,他引:3
研究了在紫外光下,用分光光度法测定聚丙烯酰胺中丙烯酰胺残留量的新方法,该方法简单,准确度、精密度好,摩尔吸光系数为1.28×104L·mol-1·cm-1,丙烯酰胺含量在0~2400μg·L-1范围内呈良好的线性关系。用于实际样品测定,取得了满意的结果。 相似文献
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为了去除水生环境中的新兴污染物卡马西平(CBZ),构建了焦亚硫酸盐耦合过二硫酸盐(K2S2O5/PDS)的均相催化体系.经过参数优化得到最佳工艺条件为:K2S2O5的浓度为3mM、PDS的浓度为5mM、初始pH值为3.5、反应温度为25℃.在该条件下反应120min后2ppmCBZ的去除率超过了95%,相比较于对照实验... 相似文献
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Leland M Vane 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2020,95(3):495-512
A recent review article (Journal of Chemical Technology & Biotechnology 94 : 343–365 (2019)) identified several commercially-available permselective materials for drying organic solvents with pervaporation (PV) and vapor permeation (V·P) separation processes. The membrane materials included polymeric and inorganic substances exhibiting a range in the performance characteristics: water permeance, water/solvent selectivity, and maximum use temperature. This article provides an overview of the factors affecting the design of PV/V·P processes utilizing these membranes to remove water from common organic solvents. Properties of the specific membrane and of the solvent substantially affect the PV/V·P separation. Equally important is the impact of operating parameters on the overall separation. To study these impacts, simplified process performance equations and detailed spreadsheet calculations were developed for single-pass and recirculating batch PV systems and for single-pass V·P systems. Estimates of membrane area, permeate concentration, solvent recovery, permeate condenser temperatures, and heating requirements were calculated. Process variables included: solvent type, water permeance, water/solvent selectivity, initial and final water concentrations, operating temperature (PV) or feed pressure (V·P), temperature drop due to evaporation (PV) or feed-side pressure drop (V·P), and permeate pressure. The target solvents considered were: acetonitrile, 1-butanol, N,N-dimethyl formamide, ethanol, methanol, methyl isobutyl ketone, methyl tert-butyl ether, tetrahydrofuran, acetone, and 2-propanol. Published 2019. This article is a U.S. Government work and is in the public domain in the USA. 相似文献
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《应用化工》2022,(9):2435-2439
采用紫外/过硫酸盐(UV/PS)高级氧化技术去除饮用水中含氮消毒副产物亚硝基二丙胺(NDPA),考察了PS投加量、NDPA初始浓度、pH值、共存阴离子对NDPA降解效率的影响,并拟合其动力学模型。结果表明,单独UV辐射以及单独PS氧化,去除效果均不显著;UV/PS联用有较高的降解效果,在反应温度为25℃、pH值为7.0、紫外光照强度为168μW/cm2下,最佳PS投加量和NDPA初始浓度分别为0.05 mmol/L和200μg/L时,UV/PS可在40 min内降解75%以上的NDPA。NDPA的降解速率随着PS投加量的增大而增大,随着NDPA初始浓度的增加而降低;随着pH值的增大而减小;共存阴离子NO2下,最佳PS投加量和NDPA初始浓度分别为0.05 mmol/L和200μg/L时,UV/PS可在40 min内降解75%以上的NDPA。NDPA的降解速率随着PS投加量的增大而增大,随着NDPA初始浓度的增加而降低;随着pH值的增大而减小;共存阴离子NO-_3对NDPA的去除具有轻微的抑制作用,而HCO-_3对NDPA的去除具有轻微的抑制作用,而HCO-_3、Cl-_3、Cl-对NDPA的去除具有一定的促进作用。其降解均符合一级动力学。 相似文献
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The organic compounds contaminated soil substantially threatens the growth of plants and food safety. In this study, we synthesis zero-valent bimetallic Fe/Cu catalysts for the degradation of 2,4-dichlorophenol (DCP) in soils with persulfate (PS) in combination of organic surfactants and exploring the main environmental impact factors. The kinetic experiments show that the 5% (mass) dosage of Fe/Cu exhibits a higher degradation efficiency (86%) of DCP in soils, and the degradation efficiency of DCP increases with the increase of the initial PS concentration. Acidic conditions are favorable for the DCP degradation in soils. More importantly, the addition of Tween-80, and Triton-100 can obviously desorb DCP from the soil surface, which enhances the degradation efficiency of DCP in soils by Fe/Cu and PS reaction system. Furthermore, the Quenching experiments demonstrate that SO4-· and ·OH are the predominant radicals for the degradation of DCP during the Fe/Cu and PS reaction system as well as non-radical also exist. The findings of this work provide an effective method for remediating DCP from soils. 相似文献
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