WO2021152569A1 - Procédé de désinfection de l'eau utilisant du ca2fe2o5 en l'absence de lumière - Google Patents

Procédé de désinfection de l'eau utilisant du ca2fe2o5 en l'absence de lumière Download PDF

Info

Publication number
WO2021152569A1
WO2021152569A1 PCT/IB2021/052390 IB2021052390W WO2021152569A1 WO 2021152569 A1 WO2021152569 A1 WO 2021152569A1 IB 2021052390 W IB2021052390 W IB 2021052390W WO 2021152569 A1 WO2021152569 A1 WO 2021152569A1
Authority
WO
WIPO (PCT)
Prior art keywords
water
ca2fe205
formulation
disinfection
light
Prior art date
Application number
PCT/IB2021/052390
Other languages
English (en)
Inventor
Andris ŠUTKA
Mārtiņš VANAGS
Linda MEŽULE
Dāvids ŠTĒBELIS
Original Assignee
Rīgas Tehniskā Universitāte
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Rīgas Tehniskā Universitāte filed Critical Rīgas Tehniskā Universitāte
Publication of WO2021152569A1 publication Critical patent/WO2021152569A1/fr

Links

Classifications

    • 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
    • C02F1/68—Treatment of water, waste water, or sewage by addition of specified substances, e.g. trace elements, for ameliorating potable water
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2303/00—Specific treatment goals
    • C02F2303/04—Disinfection
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2305/00—Use of specific compounds during water treatment
    • C02F2305/08—Nanoparticles or nanotubes
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2305/00—Use of specific compounds during water treatment
    • C02F2305/10—Photocatalysts

Definitions

  • [001] Invention relates to a water treatment technology, especially to the disinfection of water from gram-positive and a gram-negative bacteria using a formulation comprising Ca2Fe205.
  • International patent application publication No. W02019/003079 discloses a water remediation technology used for photocatalysis in visible light, for example, water purification reactors. It discloses a narrow n- and p-type semiconductor system with high oxidation-reduction potential and low photoinduced charge carrier recombination, which is provided by Z-scheme charge transfer mechanism. System contains photocatalysts from earth abundant chemical elements. Photocatalyst system Fe203/Ca2Fe205 can be used in visible light photocatalysis: (i) water purification; (ii) disinfection; (iii) air purification; (iv) sterile surfaces; (v) water splitting; (vi) synthesis of chemical compounds from ambient C02.
  • Chinese patent application publication No. CN108726626 discloses a method for treating water comprising CaFeCM under visible light conditions.
  • the present invention is a method for disinfection of liquid substances in dark, preferably a water from a gram-positive and a gram-negative bacteria using a formulation comprising Ca2Fe205.
  • the catalytic material Ca2Fe205 employed in the invention has the following physical characteristics: particle size is less than 100 nm, material purity is 99.9%, density is about lOOgr/litre, specific surface area is 13.55 m2/gr.
  • Ca2Fe205 concentration in the formulation is l.Og/L to 5.0g/L, for example Ca2Fe205 in water suspension.
  • Ca2Fe205 in water suspension has pH in the range of 8.2 to 8.8, preferably 8.5.
  • Ca2Fe205 has a light yellowish colour.
  • Brownmillerites are oxygen deficient compounds with general formulation A2B205.
  • the B are octahedral and tetrahedral site cations arranged in layers and A is a large cation occupying space between layers.
  • Srebrodolskite is member of Brownmillerite subgroup with general formulation Ca2Fe205. It is non-stoichiometric perovskite group material with orthorhombic crystal system. Mineral is named in honor of Boris Ivanovich Srebrodolsky and approved in 1984.
  • the invention includes a method for water disinfection.
  • the method consists of following steps: a) providing a formulation comprising Ca2Fe205; and b) applying said formulation comprising Ca2Fe205 to a water to disinfect thereof.
  • the step b) is performed without presence of light allowing to perform disinfection in enclosed volumes or spaces significantly improving disinfection capabilities. Without presence of any light includes no use of visible light, ultraviolet radiation and infrared light.
  • the prior art discloses other catalysts disinfectants that work only in visible light decreasing its application in water systems as most water systems are enclosed and are not designed to be subject to visible light.
  • the method further comprises a step of applying an effective amount of the formulation comprising CaFeO, preferably Ca2Fe205, to the water to be disinfected.
  • the effective amount of the formulation to the water is in the range of 0.2 to 0.7 weight%.
  • the formulation comprising Ca2Fe205 (5 g/L) in water has demonstrated a 7.5 log decrease in cultivable E. coli and 6.5 log decrease in cultivable S. aureus within 30 minutes.
  • the test was performed in the dark environment - without a presence of any light, ultraviolet radiation and infrared light.
  • the observed antimicrobial activity is due to hydroxyl radical generation as indicated by electron paramagnetic resonance measurements.
  • the method further comprising the step of applying the formulation comprising Ca2Fe205 to the water for coagulation of bacteria and other solids. Accordingly, the disinfection of water may be made without additional coagulants.
  • the key of the invention is a use of the environmentally friendly catalytic material (inorganic antimicrobial agent), that performs physical disinfection of waterborne pathogens.
  • Disinfection technology can be described as an aqueous synthase obtained catalytic material, with high disinfection efficacy on a broad spectrum of pathogens in suspended system.
  • Catalytic material has been synthesized from non-toxic earth abundant Ca and Fe elements as Ca(N03)2, Fe(N03)3, NH40H and citric acid.
  • the formulation comprising Ca2Fe205 may be prepared in a slurry including a dispersion of the formulation comprising Ca2Fe205 in water with an ultrasonic homogenizer.
  • Preparation of a powder of Ca2Fe205 for use in a disinfection of the water from gram negative and gram-positive bacteria may be performed in the following manner: a) obtaining a precursor solution in water containing the same number of moles of calcium nitrate and iron nitrate and twice the number of moles of citric acid as the number of moles of a single nitrate; b) adjusting the pH of the solution by adding NH40H dropwise; c) evaporation the water from the solution under constant stirring at 80 °C; d) the resulting mass after evaporation of water is dried at 80 °C till no mass changes can be observed; e) combustion reaction initiation at 300°C to obtain as-prepared CaiFeiOs powder; f) grinding the as-prepared Ca2Fe205 powder; and g) annealing at 800°C for 20 minutes to obtain monophasic Ca2Fe205.
  • Disinfection occurs due to radical generation and mechanical impact on bacteria membrane.
  • the radical generation is a result of structural transformations of Ca-Fe oxide in water and formation of ionised point defects that are splitting the water and generating the radicals.
  • the structural transformations also lead to the formation of flake like particles with the 2D morphology that are interacting and disrupting the bacteria membrane.
  • Fig. 1 illustrates a XRD pattern for compound Ca2Fe205.
  • the crystalline phases for as-prepared and annealed nanopowders from sol-gel auto-combustion were studied by XRD.
  • the XRD studies reveal a phase pure brownmillerite Ca2Fe205 (ICDD 00-047-1744) formation after annealing at 800 °C.
  • Ca2Fe205 effect on disinfection of liquid substances preferably a water from a gram positive and a gram-negative bacteria excluding any light, ultraviolet radiation and infrared light, is illustrated in Fig. 2.
  • Disinfection test with Ca2Fe205 catalyst was performed in filtered tap water contaminated with specific species of bacteria. The catalyst suspension was added to the contaminated water so that the catalyst concentration in the final sample was 5 g/1. In control samples, filtered tap water was used instead of the catalyst suspension. Changes in colony-forming unit (CFU) over time for E-coli and S-aureus bacteria are shown in Fig. 2. Immediately after adding the catalyst suspension to the contaminated water, a sample was taken.
  • CFU colony-forming unit
  • Fig. 3 illustrates a degradation of S. aureus bacteria during the time at different powder or catalyst concentrations.
  • Pre-filtered tap water (0.2 pm pore size filters, pH range of > 6.5 and ⁇ 9.5) complying to EU Directive 2020/2184 on the quality of water intended for human consumption was used in all microbial activity tests.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Health & Medical Sciences (AREA)
  • Medicinal 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)
  • Physical Water Treatments (AREA)
  • Agricultural Chemicals And Associated Chemicals (AREA)
  • Medicines Containing Material From Animals Or Micro-Organisms (AREA)

Abstract

L'invention concerne une technologie de traitement de l'eau, en particulier la désinfection de l'eau contre les bactéries à gram positif et à gram négatif à l'aide d'une formulation comprenant du Ca2Fe2O5. L'invention concerne en outre un procédé de désinfection de l'eau, ce procédé comprenant les étapes consistant : a) à fournir une formulation comprenant du Ca2Fe2O5 ; b) à appliquer ladite formulation à une eau pour désinfecter celle-ci, cette étape étant effectuée sans présence de lumière. L'invention concerne également un matériau catalytique respectueux de l'environnement qui effectue une désinfection physique d'agents pathogènes de l'eau.
PCT/IB2021/052390 2020-06-19 2021-03-23 Procédé de désinfection de l'eau utilisant du ca2fe2o5 en l'absence de lumière WO2021152569A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
LVLVP2020000046 2020-06-19
LVP-20-46A LV15557A (lv) 2020-06-19 2020-06-19 Metode ūdens dezinfekcijai, izmantojot CaFeO

Publications (1)

Publication Number Publication Date
WO2021152569A1 true WO2021152569A1 (fr) 2021-08-05

Family

ID=74872461

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/IB2021/052390 WO2021152569A1 (fr) 2020-06-19 2021-03-23 Procédé de désinfection de l'eau utilisant du ca2fe2o5 en l'absence de lumière

Country Status (2)

Country Link
LV (1) LV15557A (fr)
WO (1) WO2021152569A1 (fr)

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB427199A (en) * 1933-11-27 1935-04-17 Atilio Antonio Manuel Bado Improvements in the purification of water
CN108726626A (zh) 2018-05-31 2018-11-02 武汉工程大学 一种含有可见光响应型CaFe2O4催化剂的水处理剂及水处理方法
WO2019003079A1 (fr) 2017-06-26 2019-01-03 Rīgas Tehniskā Universitāte Système photocatalytique à base de fe 2o3/ca2fe2o 5

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111268784B (zh) * 2020-03-05 2022-12-02 浙江工业大学 一种多相类芬顿体系处理有机废水的方法

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB427199A (en) * 1933-11-27 1935-04-17 Atilio Antonio Manuel Bado Improvements in the purification of water
WO2019003079A1 (fr) 2017-06-26 2019-01-03 Rīgas Tehniskā Universitāte Système photocatalytique à base de fe 2o3/ca2fe2o 5
CN108726626A (zh) 2018-05-31 2018-11-02 武汉工程大学 一种含有可见光响应型CaFe2O4催化剂的水处理剂及水处理方法

Non-Patent Citations (4)

* Cited by examiner, † Cited by third party
Title
EL-RAFEI A M ET AL: "Electrospun magnetically separable calcium ferrite nanofibers for photocatalytic water purification", JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS, ELSEVIER, AMSTERDAM, NL, vol. 428, 11 December 2016 (2016-12-11), pages 92 - 98, XP029927903, ISSN: 0304-8853, DOI: 10.1016/J.JMMM.2016.12.020 *
GANGULY PRIYANKA ET AL: "Antimicrobial activity of photocatalysts: Fundamentals, mechanisms, kinetics and recent advances", APPLIED CATALYSIS B. ENVIRONMENTAL, vol. 225, 1 June 2018 (2018-06-01), AMSTERDAM, NL, pages 51 - 75, XP055812761, ISSN: 0926-3373, DOI: 10.1016/j.apcatb.2017.11.018 *
VANAGS MARTINS ET AL: "Sol-gel auto-combustion synthesis of Ca2Fe2O5 brownmillerite nanopowders and thin films for advanced oxidation photoelectrochemical water treatment in visible light", JOURNAL OF ENVIRONMENTAL CHEMICAL ENGINEERING, vol. 7, no. 4, 1 August 2019 (2019-08-01), NL, pages 103224, XP055813228, ISSN: 2213-3437, DOI: 10.1016/j.jece.2019.103224 *
WHEELER GARRETT P. ET AL: "Investigation of p-type Ca 2 Fe 2 O 5 as a Photocathode for Use in a Water Splitting Photoelectrochemical Cell", ACS APPLIED ENERGY MATERIALS, vol. 1, no. 9, 24 September 2018 (2018-09-24), pages 4917 - 4923, XP055812765, ISSN: 2574-0962, Retrieved from the Internet <URL:https://pubs.acs.org/doi/pdf/10.1021/acsaem.8b00934> DOI: 10.1021/acsaem.8b00934 *

Also Published As

Publication number Publication date
LV15557A (lv) 2021-03-20

Similar Documents

Publication Publication Date Title
Podporska-Carroll et al. Antibacterial properties of F-doped ZnO visible light photocatalyst
Kaur et al. Solar light active silver/iron oxide/zinc oxide heterostructure for photodegradation of ciprofloxacin, transformation products and antibacterial activity
Nezamzadeh-Ejhieh et al. Enhancement of the photocatalytic activity of ferrous oxide by doping onto the nano-clinoptilolite particles towards photodegradation of tetracycline
Janani et al. Nanostructured layered double hydroxides based photocatalysts: Insight on synthesis methods, application in water decontamination/splitting and antibacterial activity
KR101659456B1 (ko) 초미세먼지 차단용 기능성 크림
Almahri The solid-state synthetic performance of bentonite stacked manganese ferrite nanoparticles: adsorption and photo-fenton degradation of MB dye and antibacterial applications
KR100836527B1 (ko) 다공성 나노 미립자 티타니아 광촉매를 이용한 적조, 녹조,규조 제거용 조성물 및 상기 조성물의 제조방법 및 상기조성물을 이용한 수중의 적조, 녹조, 규조 제거방법
Piva et al. Antibacterial and photocatalytic activity of ZnO nanoparticles from Zn (OH) 2 dehydrated by azeotropic distillation, freeze drying, and ethanol washing
Farooq et al. Ultra efficient 4-Nitrophenol reduction, dye degradation and Cr (VI) adsorption in the presence of phytochemical synthesized Ag/ZnO nanocomposite: A view towards sustainable chemistry
CA2933373A1 (fr) Produits d&#39;oxyde formes de poudre de carbonate calcinee a utiliser commebiocide, detoxifiant chimique et produits de support de catalyseur
Vandani et al. Preparation of magnetic Fe3O4/MoO3/MCM-22 photocatalyst and its study on metronidazole adsorption, degradation, and process optimization
Kumar et al. Synthesis and use of low-band-gap ZnO nanoparticles for water treatment
Vikal et al. Surface functionalized silver-doped ZnO nanocatalyst: a sustainable cooperative catalytic, photocatalytic and antibacterial platform for waste treatment
Dolaberidze et al. Silver-and zinc-containing bactericidal phillipsites
Visinescu et al. Additive-free 1, 4-butanediol mediated synthesis: a suitable route to obtain nanostructured, mesoporous spherical zinc oxide materials with multifunctional properties
US8231790B2 (en) Process for producing an anion adsorbent and anion adsorbent produced by said process
Tatarchuk et al. Fenton-like water disinfection using fixed-bed reactor filled with a CoFe2O4 catalyst: Mechanisms, the impact of anions, electromagnetic heating, and toxicity evaluation
Tsitsishvili et al. BACTERICIDAL ADSORBENTS OBTAINED BY ION EXCHANGE MODIFICATION OF NATURAL PHILLIPSITE.
WO2021152569A1 (fr) Procédé de désinfection de l&#39;eau utilisant du ca2fe2o5 en l&#39;absence de lumière
Hernandez Maldonado et al. Removal of chromium from contaminated liquid effluents using natural brushite obtained from bovine bone.
Önkal-Engin et al. Humic acid uptake from aqueous media using hydrotalcites and modified montmorillonite
Chitra et al. Structural, morphological and optical properties of CuAl2O4 nanoparticles and their applications for photocatalytic and antibacterial activities
Tatarchuk et al. Copper-substituted magnetite as a Fenton-like catalyst boosted with electromagnetic heating
Alatabe Photocatalytic degradation of oxamyl pesticide by adsorption using bentonite/titanium dioxide nanocomposite doped with nickel
Labrag et al. Antibiotic photocatalysis and antimicrobial activity of low-cost multifunctional Fe3O4@ HAp nanocomposites

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 21717967

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 21717967

Country of ref document: EP

Kind code of ref document: A1