WO2021208305A1 - 一种利用蒙脱土吸附剂去除水体中氟磺隆的方法 - Google Patents

一种利用蒙脱土吸附剂去除水体中氟磺隆的方法 Download PDF

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WO2021208305A1
WO2021208305A1 PCT/CN2020/108826 CN2020108826W WO2021208305A1 WO 2021208305 A1 WO2021208305 A1 WO 2021208305A1 CN 2020108826 W CN2020108826 W CN 2020108826W WO 2021208305 A1 WO2021208305 A1 WO 2021208305A1
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water
montmorillonite
flusulfuron
prosulfuron
adsorbent
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PCT/CN2020/108826
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French (fr)
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任文杰
赵玲
周晓飞
许有仁
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南京融众环境工程研究院有限公司
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Publication of WO2021208305A1 publication Critical patent/WO2021208305A1/zh

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    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/28—Treatment of water, waste water, or sewage by sorption
    • C02F1/281—Treatment of water, waste water, or sewage by sorption using inorganic sorbents
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2101/00—Nature of the contaminant
    • C02F2101/30—Organic compounds
    • C02F2101/306—Pesticides

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  • the invention belongs to the technical field of treatment of polluted water bodies, and in particular relates to a method for removing triflusulfuron in water using a montmorillonite adsorbent, and is applied to the technical field of treatment of contaminated water polluted by trifluorosulfuron.
  • Flusulfuron is a new type of sulfonylurea herbicide with high efficiency and low toxicity. It is widely used in the control of broadleaf weeds and certain grassy weeds in cereal crops.
  • flusulfuron-methyl Due to the advantages of high herbicidal activity, low dosage and high safety, flusulfuron-methyl has been widely used in China and even the world. According to reports, after pesticide application, only 10-20% is effectively used, and the rest is lost to the soil environment. However, because flusulfuron and other sulfonylurea herbicides are weakly adsorbed on the soil and have relatively high mobility, they can enter surface water or underground diving in the form of rainwater leaching; in addition, flusulfuron can also be discharged through production plants The sewage enters the river, causing local water pollution, and can also form a phenomenon of eutrophication in the water body, causing serious harm to aquatic organisms.
  • the main treatment methods for pesticide pollution in water bodies are chemical oxidation, biological and adsorption methods.
  • the chemical oxidation method has high removal efficiency, but it needs to add a large amount of oxidants to the water body, and a large amount of difficult-to-degrade intermediate products may be produced during the treatment process, causing secondary pollution; although the biological method has a low operating cost, the removal effect is unstable and easy Affected by environmental conditions such as temperature and pH value, the pollutant content in the water after treatment still cannot meet the standard; and the adsorption method has the advantages of simple operation, wide applicability, and low economic cost, and it is a removal with wide application potential. Methods of pesticide contamination.
  • Montmorillonite is a natural mineral of silicate. After adding water, its volume can expand several times and become a paste, and its volume shrinks after being heated and dehydrated. It has strong adsorption capacity and cation exchange performance, mainly produced in the weathering crust of volcanic tuff.
  • montmorillonite has significant advantages such as stable properties, high specific surface area, good dispersibility, and low price. It is widely used as adsorbents, catalysts, and coating agents for pollutants, and has broad application prospects. However, the application of montmorillonite as an adsorbent to remove triflusulfuron in water has not been reported yet.
  • the present invention provides a method for removing flusulfuron from water by using a montmorillonite adsorbent.
  • the object of the present invention is to provide a method for removing flusulfuron from water using montmorillonite adsorbent, which can effectively remove flusulfuron from water, and has stable removal effect, corrosion resistance, heat resistance and non-toxicity
  • the montmorillonite used in the present invention has low energy consumption, is economical and environmentally friendly, has a wide range of application prospects, and provides a new method for the removal of flusulfuron in water bodies.
  • the present invention provides a method for removing flusulfuron from water using a montmorillonite adsorbent, which includes the following steps: first add montmorillonite to flusulfuron-polluted water, and then stir or oscillate the water for a certain period of time, and Centrifugal filtration, and finally the montmorillonite adsorbing flusulfuron-methyl is separated from the treated water body to realize the removal of flusulfuron-methyl in the water body.
  • the initial pollution concentration of triflusulfuron in the water body is 3.0-16.0 mg/L.
  • the addition amount of the montmorillonite is 5.0 g/L.
  • the stirring or shaking time is not less than 12h.
  • the suitable temperature for stirring or shaking is 15-25°C.
  • the centrifugal speed is 3000 r/min, and the centrifugal time is 15 min.
  • the beneficial effects of the method for removing trifluorosulfuron in water by using montmorillonite adsorbent of the present invention are as follows: 1.
  • the present invention uses montmorillonite adsorbent, which has a large adsorption capacity and a removal effect. The advantages of stability, corrosion resistance, heat resistance and non-toxicity; 2.
  • the present invention uses montmorillonite with stable properties, high specific surface area, good dispersibility, and low economic cost as the adsorbent to realize the high efficiency of flusulfuron in water Adsorption removal; 3.
  • the present invention uses montmorillonite to adsorb flusulfuron and sink to the bottom of the water, which is beneficial to the recovery and reuse of the adsorbent, avoids the secondary pollution of the adsorbent, and further reduces the economic cost.
  • humic acid on flusulfuron in water is generally considered to be better for the adsorption and removal of organic matter. Therefore, this example measured the adsorption and removal effect of humic acid on flusulfuron in water to compare with Montmorillonite for comparison.
  • humic acid 100 mg
  • the background solution is a solution of 0.01M CaCl 2 and 200 mg L -1 NaN 3 (inhibition of microbial activity).
  • centrifuge for 15 minutes at 3000r min -1 take the supernatant, filter it through a 0.45 ⁇ m aqueous filter membrane, and determine the concentration of flusulfuron in the filtrate by high performance liquid chromatography. The treatments were repeated in three times, and three treatments without humic acid were used as controls.
  • Table 1 shows the adsorption effect of humic acid on flusulfuron-methyl in water. It can be seen from Table 1 that when the initial concentration in the water body is 3.079-17.067 mg/L, the adsorption percentage of humic acid on the trisulfuron-methyl in the water body is only 27.09-32.77%, and the removal effect is poor.
  • the adsorption and removal effect of montmorillonite on flusulfuron in water Weigh a certain amount of montmorillonite (100mg) into a 50mL glass centrifuge tube and add 20mL of background solution containing flusulfuron (concentration of 3-16mg L -1) ).
  • the background solution is a solution of 0.01M CaCl 2 and 200 mg L -1 NaN 3 (inhibition of microbial activity). After shaking on a rotary shaker for 24 hours at room temperature, centrifuge for 15 minutes at 3000r min -1 , take the supernatant, filter it through a 0.45 ⁇ m aqueous filter membrane, and determine the concentration of flusulfuron in the filtrate by high performance liquid chromatography.
  • Table 2 shows the adsorption effect of montmorillonite on flusulfuron-methyl in water. It can be seen from Table 2 that when the initial concentration in the water body is 3.335-16.218 mg/L, the adsorption percentage of montmorillonite to flusulfuron in the water body can reach 78.81-88.35%, which is much higher than that of humic acid for flusulfuron-methyl.
  • Adsorption percentage the adsorption capacity of montmorillonite to flusulfuron can reach 0.564-2.866mg/g, showing high adsorption capacity, and the adsorption capacity increases with the increase of the initial concentration, which can effectively remove fluorine in the water body Sulfuron-methyl.

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  • Chemical & Material Sciences (AREA)
  • Inorganic Chemistry (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Hydrology & Water Resources (AREA)
  • Engineering & Computer Science (AREA)
  • Environmental & Geological Engineering (AREA)
  • Water Supply & Treatment (AREA)
  • Organic Chemistry (AREA)
  • Water Treatment By Sorption (AREA)

Abstract

本发明属于污染水体处理应用技术领域，具体公开了一种利用蒙脱土吸附剂去除水体中氟磺隆的方法，包括以下步骤，首先向氟磺隆污染水体中加入蒙脱土，再将水体搅拌或振荡一定时间，并离心过滤，最后将吸附氟磺隆的蒙脱土与处理后的水体分离，实现水体中氟磺隆的去除。本发明的一种利用蒙脱土吸附剂去除水体中氟磺隆的方法的有益效果在于：能有效去除水体中的氟磺隆，还具备去除效果稳定、耐腐蚀、耐热和无毒等优势，同时本发明使用蒙脱土能耗低、经济环保，具有广泛的应用前景。

Description

一种利用蒙脱土吸附剂去除水体中氟磺隆的方法 技术领域
本发明属于污染水体处理应用技术领域，具体涉及一种利用蒙脱土吸附剂去除水体中氟磺隆的方法，应用于氟磺隆污染废水处理技术领域。
背景技术
氟磺隆是一种高效、低毒的新型磺酰脲类除草剂，广泛用于禾谷作物防除阔叶杂草以及某些禾本科杂草。
由于具有除草活性高、用量低、安全性高等优点，氟磺隆在我国乃至世界范围内得到大面积应用。据报道，农药施用后，被有效利用部分仅占10-20％，其余全部流失进入土壤环境中。但由于氟磺隆等磺酰脲类除草剂在土壤上吸附较弱，移动性相对较大，可随雨水淋溶的方式进入地表水或地下潜水中；此外，氟磺隆也可以通过生产工厂排放的污水进入到河流中，造成地方性的水体污染，还能在水体中形成富营养化的现象，对水中生物产生严重危害。
近年来，氟磺隆在水体中的残留问题引起了各国环保学者们的广泛关注。欧盟委员会规定，氟磺隆在同一区域的使用频率限于三年使用一次，每次使用最大剂量<20g/ha。欧盟委员会同时提醒成员国特别注意：当氟磺隆应用于土壤或者气候条件较脆弱的地区时，需要考虑对非目标陆生和水生植物造成的风险。因此，去除水体中的氟磺隆污染对人体健康和生态环境保护具有重要的现实意义。
目前，水体中农药污染的主要治理手段有化学氧化法、生物法和吸附法。化学氧化法去除效率高，但需要向水体中加入大量氧化剂，且处理过程中可能会产生大量难降解的中间产物，造成二次污染；生物法尽管运行成本较低，但去除效果不稳定，易受到温度、pH值等环境条件的影响，从而导致处理后水体中污染物含量仍然不能达标；而吸附法具有操作简便、适用性广、经济成本低等优势，是一种具有广泛应用潜力的去除农药污染的方法。
但目前关于水体中氟磺隆的吸附去除方法还未见报道，其关键是找到一种合适的吸附剂。蒙脱土是一种硅酸盐的天然矿物，加水后其体积可膨胀数倍，并变成糊状物，受热脱水后体积收缩。具有很强的吸附能力和阳离子交换性能，主要产于火山凝灰岩的风化壳中。此外，蒙脱土因具备性质稳定、比表面积高、分散 性好、价格低廉等显著优势，广泛用于污染物的吸附剂、催化剂、涂层剂，应用前景广阔。但应用蒙脱土作为吸附剂来去除水体中的氟磺隆仍未见报道。
因此，基于上述问题，本发明提供一种利用蒙脱土吸附剂去除水体中氟磺隆的方法。
发明内容
发明目的：本发明的目的是提供一种利用蒙脱土吸附剂去除水体中氟磺隆的方法，能有效去除水体中的氟磺隆，还具备去除效果稳定、耐腐蚀、耐热和无毒等优势，同时本发明使用蒙脱土能耗低、经济环保，具有广泛的应用前景，为水体中氟磺隆去除提供了一种新的方法。
技术方案：本发明提供一种利用蒙脱土吸附剂去除水体中氟磺隆的方法，包括以下步骤，首先向氟磺隆污染水体中加入蒙脱土，再将水体搅拌或振荡一定时间，并离心过滤，最后将吸附氟磺隆的蒙脱土与处理后的水体分离，实现水体中氟磺隆的去除。
本技术方案的，所述水体中氟磺隆的初始污染浓度为3.0-16.0mg/L。
本技术方案的，所述蒙脱土的添加量为5.0g/L。
本技术方案的，所述搅拌或振荡时间为不低于12h。
本技术方案的，所述搅拌或振荡的适合温度为15-25℃。
本技术方案的，所述离心转速为3000r/min，离心时间为15min。
与现有技术相比，本发明的一种利用蒙脱土吸附剂去除水体中氟磺隆的方法的有益效果在于：1、本发明使用蒙脱土吸附剂，吸附容量大，同时具备去除效果稳定、耐腐蚀、耐热和无毒等优势；2、本发明使用性质稳定、高比表面积、分散性好、经济成本低的蒙脱土为吸附剂，实现了对水体中氟磺隆的高效吸附去除；3、本发明使用蒙脱土吸附氟磺隆后沉于水底，有利于吸附剂的回收再利用，避免了吸附剂的二次污染，并进一步降低了经济成本。
具体实施方式
下面结合具体实施例，进一步阐明本发明。
实施例一
腐殖酸对水体中氟磺隆的吸附去除效果，通常认为腐殖酸对有机物的吸附去 除效果更好，因此本实施例测定了腐殖酸对水体中氟磺隆的吸附去除效果，以便与蒙脱土进行对比。
称取一定量的腐殖酸(100mg)于50mL玻璃离心管中，加入20mL含有氟磺隆的背景溶液(浓度为3-16mg L -1)。背景溶液为0.01M CaCl 2和200mg L -1NaN 3(抑制微生物活动)溶液。在室温条件下于旋转振荡器上振荡24h后，以3000r min -1离心15min，取上清液，经0.45μm水性滤膜过滤后，用高效液相色谱测定滤液中氟磺隆的浓度，以上处理均做三个重复，并采用三个不含腐殖酸的处理作为对照。表1为腐殖酸对水体中氟磺隆的吸附效果。由表1可见，当水体中初始浓度为3.079-17.067mg/L时，腐殖酸对水体中氟磺隆的吸附百分比仅仅为27.09-32.77％，去除效果较差。
表1 腐殖酸对水体中氟磺隆的吸附效果
初始浓度(mg/L) 吸附百分比
3.079 32.77％
5.631 30.12％
7.894 28.29％
10.128 27.09％
13.827 28.28％
17.067 28.70％
实施例二
蒙脱土对水体中氟磺隆的吸附去除效果，称取一定量的蒙脱土(100mg)于50mL玻璃离心管中，加入20mL含有氟磺隆的背景溶液(浓度为3-16mg L -1)。背景溶液为0.01M CaCl 2和200mg L -1NaN 3(抑制微生物活动)溶液。在室温条件下于旋转振荡器上振荡24h后，以3000r min -1离心15min，取上清液，经0.45μm水性滤膜过滤后，用高效液相色谱测定滤液中氟磺隆的浓度，以上处理均做三个重复，并采用三个不含蒙脱土的处理作为对照。表2为蒙脱土对水体中氟磺隆的吸附效果。由表2可见，当水体中初始浓度为3.335-16.218mg/L时，蒙脱土对水体中氟磺隆的吸附百分比可以达到78.81-88.35％，远远高于腐殖酸对氟磺隆的吸附百分比，蒙脱土对氟磺隆的吸附量可以达到0.564-2.866mg/g， 表现出较高的吸附能力，而且吸附量随着初始浓度的升高而增大，能够有效去除水体中氟磺隆。
表2 蒙脱土对水体中氟磺隆的吸附效果
初始浓度(mg/L) 吸附百分比 吸附量(mg/g)
3.335 84.57％ 0.564
5.430 80.79％ 0.877
7.488 78.81％ 1.180
9.719 82.26％ 1.599
12.955 85.91％ 2.225
16.218 88.35％ 2.866
。
以上所述仅是本发明的优选实施方式，应当指出，对于本技术领域的普通技术人员来说，在不脱离本发明原理的前提下，还可以作出若干改进，这些改进也应视为本发明的保护范围。

Claims (6)

  1. 一种利用蒙脱土吸附剂去除水体中氟磺隆的方法，其特征在于：包括以下步骤，首先向氟磺隆污染水体中加入蒙脱土，再将水体搅拌或振荡一定时间，并离心过滤，最后将吸附氟磺隆的蒙脱土与处理后的水体分离，实现水体中氟磺隆的去除。
  2. 根据权利要求1所述的一种利用蒙脱土吸附剂去除水体中氟磺隆的方法，其特征在于：所述水体中氟磺隆的初始污染浓度为3.0-16.0mg/L。
  3. 根据权利要求1所述的一种利用蒙脱土吸附剂去除水体中氟磺隆的方法，其特征在于：所述蒙脱土的添加量为5.0g/L。
  4. 根据权利要求1所述的一种利用蒙脱土吸附剂去除水体中氟磺隆的方法，其特征在于：所述搅拌或振荡时间为不低于12h。
  5. 根据权利要求1所述的一种利用蒙脱土吸附剂去除水体中氟磺隆的方法，其特征在于：所述搅拌或振荡的适合温度为15-25℃。
  6. 根据权利要求1所述的一种利用蒙脱土吸附剂去除水体中氟磺隆的方法，其特征在于：所述离心转速为3000r/min，离心时间为15min。
PCT/CN2020/108826 2020-04-14 2020-08-13 一种利用蒙脱土吸附剂去除水体中氟磺隆的方法 WO2021208305A1 (zh)

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Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102583673A (zh) * 2012-02-27 2012-07-18 中国科学院南京土壤研究所 蒙脱石去除水体中草甘膦的方法
CN105883962A (zh) * 2016-04-13 2016-08-24 上海大学 利用膨胀石墨吸附剂去除水体中抗生素-磺胺嘧啶的方法
CN111362348A (zh) * 2020-04-14 2020-07-03 南京融众环境工程研究院有限公司 一种利用蒙脱土吸附剂去除水体中氟磺隆的方法

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20090114599A1 (en) * 2005-01-18 2009-05-07 Yissum Research Development Company Of The Hebrew University Of Jerusalem Removal Of Organic Pollutants From Contaminated Water
US8372283B2 (en) * 2010-07-09 2013-02-12 Earth Renaissance Technologies, Llc Treatment method reducing wastewater influent chemical/pharmaceuticals before biological reduction to enhance sewage treatment
CN105498692B (zh) * 2016-01-29 2018-03-13 太原科技大学 基于玉米秸秆的生物碳农药吸附材料的制备和使用方法
CN105948158A (zh) * 2016-06-03 2016-09-21 上海大学 利用活性炭纤维吸附剂去除水体中抗生素-磺胺嘧啶的方法

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102583673A (zh) * 2012-02-27 2012-07-18 中国科学院南京土壤研究所 蒙脱石去除水体中草甘膦的方法
CN105883962A (zh) * 2016-04-13 2016-08-24 上海大学 利用膨胀石墨吸附剂去除水体中抗生素-磺胺嘧啶的方法
CN111362348A (zh) * 2020-04-14 2020-07-03 南京融众环境工程研究院有限公司 一种利用蒙脱土吸附剂去除水体中氟磺隆的方法

Non-Patent Citations (3)

* Cited by examiner, † Cited by third party
Title
SEUNGHUN HYUN,LINDA S. LEE: "Factors Controlling Sorption of Prosulfuron by Variable-Charge Soils and Model Sorbents", JOURNAL OF ENVIRONMENTAL QUALITY, vol. 33, no. 4, 31 July 2004 (2004-07-31), pages 1354 - 1361, XP055857597, ISSN: 0047-2425, DOI: 10.2134/jeq2004.1354 *
WANG TAO;YUAN WENLI;ZHONG XIAOXIAO;LIU YONGHONG;YUE XIALI;ZHOU GUANGSHENG: "Effects of Organically Modified Bentonite and Attapulgite on Adsorption of Chlorsulfuron", JOURNAL OF HUAZHONG AGRICULTURAL UNIVERSITY, vol. 37, no. 1, 8 January 2018 (2018-01-08), CN, pages 69 - 74, XP055857592, ISSN: 1000-2421, DOI: 10.13300/j.cnki.hnlkxb.2018.01.012 *
ZHANG JIN , SI YOUBIN: "Adsorption of Herbicide Ethametsulfuron-methyl on Minerals and Modified by Organics", ANHUI AGRICULTURAL SCIENCE BULLETIN, vol. 13, no. 6, 16 March 2007 (2007-03-16), pages 24 - 25+35, XP055857586, ISSN: 1007-7731, DOI: 10.16377/j.cnki.issn1007-7731.2007.06.014 *

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