CN101142922B - Tourmaline chromium-loaded inhibiting sulfate reducing bacteria powder and its preparation method - Google Patents

Tourmaline chromium-loaded inhibiting sulfate reducing bacteria powder and its preparation method Download PDF

Info

Publication number
CN101142922B
CN101142922B CN2007100727622A CN200710072762A CN101142922B CN 101142922 B CN101142922 B CN 101142922B CN 2007100727622 A CN2007100727622 A CN 2007100727622A CN 200710072762 A CN200710072762 A CN 200710072762A CN 101142922 B CN101142922 B CN 101142922B
Authority
CN
China
Prior art keywords
tourmaline
inhibition
chromium
powder agent
sulphate reduction
Prior art date
Legal status (The legal status 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 status listed.)
Expired - Fee Related
Application number
CN2007100727622A
Other languages
Chinese (zh)
Other versions
CN101142922A (en
Inventor
马放
魏利
王博
孙伟
王强
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Harbin Institute of Technology
Original Assignee
Harbin Institute of Technology
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 Harbin Institute of Technology filed Critical Harbin Institute of Technology
Priority to CN2007100727622A priority Critical patent/CN101142922B/en
Publication of CN101142922A publication Critical patent/CN101142922A/en
Application granted granted Critical
Publication of CN101142922B publication Critical patent/CN101142922B/en
Expired - Fee Related legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Landscapes

  • Agricultural Chemicals And Associated Chemicals (AREA)
  • Pharmaceuticals Containing Other Organic And Inorganic Compounds (AREA)

Abstract

The invention provides a tourmaline powder containing chromium for inhibition of sulfate reduction and a preparation method, which relates to biological antibacterial agent of inorganic antibacterial material and a preparation method. The invention solves the problem that the growth of large number of sulfate-reducing bacteria brings danger to environment. The tourmaline powder containing chromium for inhibition of sulfate reduction provided by the invention consists of a tourmaline and a chromium chloride, the chromium chloride is loaded on the tourmaline with surface modification, ion exchange and solid-phase synthesis, the particle diameter of the tourmaline is 50nm to 800nm, and the quality percentage of the chromium chloride in the tourmaline is 0.01 percent to 40 percent. The preparation method is that suspension solution is made of the tourmaline powder and deionized water and then PH value is adjusted to 4-8 with nitrate solution; the chromium chloride solid and a dispersant are added in serial, and then after stirring and filtering, the sediment undergoes washing, drying, grinding, calcinations and then grinding. The invention can be used for inhibition of reduction of the sulfate-reducing bacteria and can be widely used for environmental remediation or treatment.

Description

Suppress tourmaline carried chromium powder agent of sulphate reduction and preparation method thereof
Technical field:
The present invention relates to the preparation method of the biological bacteriostatic agent of inorganic antibacterial material.
Background technology:
Existing bacteriostasis method can be divided into physics, chemistry, biological three kinds, in addition, also can in base material, add antibacterial agent and reach antibiotic purpose.Physical method is by changing temperature, pressure and using physical means sterilizations such as electromagnetic wave, electron ray; Chemical method then is by regulating the pH value, carrying out means sterilizations such as gas exchange, dehydration, isolation nutrient source.It is 3 big classes that the kind of antibacterial agent can be divided into inorganic system, organic system and natural biological substantially.Natural antibacterial agent is mainly the extract of natural plants, is subjected to the restriction of resource, and application has certain difficulty; When selecting organic antibacterial agent for use, except that considering its safety, also there is poor heat resistance in the existing quite long history of the application of organic antibacterial agent, easily decomposes and problem such as service life is short; It is that natural or artificial mineral's material etc. are as carrier that inorganic bacteriostatic agent is meant with inorganic material, major part, be loaded with a kind of inorganic antiseptic that the metallic element that possesses certain antibacterial ability and metal ion and the antibacterial material of nanometer are developed, inorganic antiseptic combines by high efficiency, the broad spectrum activity of stability that inorganic material is intrinsic and antimicrobial component, has successfully overcome the shortcoming of organic antibacterial agent.
Tourmaline is with a wide range of applications as a kind of novel environment friendly material.The chemical composition of tourmaline mineral is very complicated, after the 1950's its crystal structure being determined, just proposes relatively rational structure general formula, and its general formula is expressed as: XY 3Z 6Si 6O 18(BO 3) 3W 4, X is mainly by Na or Ca in the formula OrK, perhaps the part room occupies; Y is mainly by Fe 2+(or) Mg 2+, Al + 3± Li +Or Fe 3+, usually also by Mn 2+And Mn 3+Occupy; Z is mainly by Al 3+, Fe 3+Or Cr 3+Occupy, also may comprise Mg 2+And V 3+W is by OH -, F -, O -2Occupy.X, Y, the different colors that can influence tourmaline of the atom of three positions of Z or ionic species.The tourmaline crystal structure belongs to trigonal system, C 5 3v-R3m group is so tourmaline is the heteropolarity mineral.
Japanese scholar Kubo in 1989 finds that there is spontaneous permanent electric polarity in tourmaline.Tourmaline is abundanter in the resource of China, and its environmental activity is compared with the natural ferrimanganic aluminum oxide of using always, silicate hydroxide minerals, zeolite, diatomite, lightweight opal etc., and is noticeable owing to producing anion and electropolar existence thereof.Because there is spontaneous permanent electric polarity in tourmaline, other characteristics of tourmaline just constantly for the mankind cognition.Studies confirm that in recent years, tourmaline have 5 specific characters: produce anion, brine electrolysis, dwindle hydrone, emitting far-infrared 4～14um wavelength, contain effective trace mineral.Tourmaline remains to be furtherd investigate to the research and the application of sanitary sewage disposal.Exploitation along with natural self-purification, environment functional material; the application of relevant tourmaline aspect environmental protection also increases gradually; if with the tourmaline is the preparing carriers inorganic antiseptic, then antibacterial agent not only has antibacterial functions, also has not available other function of other inorganic antiseptic.
(sulfate reducing bacteria SRB) is the general name of the class bacterium relevant with sulfate reduction to sulfate reducing bacteria.Microorganism by numerous species constitutes, comprise Gram-negative bacteria (as Desulfovibrio Desulfovibrio, Desulfobacter Desulfobacterium), gram-positive bacteria (Desulfotomaculum Desulfotomaculum), thermophilic bacteria (thermally desulfurizing Pseudomonas Thermodesulfobacterium) and thermophilic archeobacteria (ancient green-ball Pseudomonas Archaeoglobus) etc.
Over nearly more than 20 years, along with the accelerated development of national economy, the industrial wastewater particularly pollution of sulfate wastewater is quite serious.A lot of big cities underground water of China has been subjected to sulfate contamination in various degree.Sulfur acid salt acidic waste water directly enters water body without processing will make the receiving water body acidifying, reduce water pH value, the harm aquatile, and produce potential corrosion; This class acidic waste water also can destroy soil structure, reduces crop yield.The sulfate wastewater latency period is long, though the diluting effect of nature is arranged, does not have tangible negative effect at short notice, in case large-area formation is polluted, then its difficulty of governance is very big.If take suitable control measure, change waste water is recycling water resource, will promote the coordinated development of economy and environment widely.It extensively is present in occurring in natures such as paddy field, lake, natural pond, rivers and creeks bed mud, petroleum deposit.
In the process of field produces, the breeding of sulfate reducing bacteria can cause a lot of harm, as corrosion product in the ground system---water-fast metal sulfide, cause sewage blackout, suspended solids content to increase, make and handle that suspended solids content exceeds standard in the water of back.The activity that how to suppress sulfate reducing bacteria has effectively become a problem that urgency is to be solved of field produces.
At Zhao Xuejun, people such as Wu Xinghui are in the paper " research of crude tourmaline carrying silver antimicrobials " that Yunnan University's journal in 2006 is delivered, adopt the crude tourmaline of particle diameter about 20 μ m, the employing solid-phase synthesis is synthetic, make tourmaline carried silver antibacterial agent by the ground and mixed calcining method, its research method and means are had any different in the patent of patent applicant's application, and its existence wastes natural resources the shortcoming of promotion and application difficulty.
Summary of the invention:
In order to solve because a large amount of growth of sulfate reducing bacteria, the invention provides a kind of tourmaline carried chromium powder agent that suppresses the sulphate reduction and preparation method thereof to the serious harm that environment brings.
The tourmaline carried chromium powder agent of inhibition sulphate reduction of the present invention is made up of tourmaline and chromium chloride, adopt surface modification and ion exchange and solid-phase synthesis that described chromium chloride is downloaded on institute's tourmaline, the particle diameter of described tourmaline is 50nm～800nm, and it is 0.01%～40% that described chromium chloride accounts for the tourmaline mass percent.
The preparation method's of the tourmaline carried chromium powder agent of inhibition sulphate reduction concrete steps are:
Step 1, be that the tourmaline powder of 50nm～800nm joins in the deionized water, in magnetic stirring apparatus, at the uniform velocity stir, make the aaerosol solution of 0.1g/ml particle diameter;
Add the nitrate solution of 0.03mol/L in step 2, the aaerosol solution that in step 1, obtains, and to adjust the pH value be 4～8;
Step 3, in the mixed solution that step 2 obtains, add the chromium chloride solid of tourmaline powder mass percent 0.01%～40% described in the step 1, and add 1.5%～2.5% polyethylene glycol dispersant, stirred 4～5 hours;
The mixed solution that step 4, filtration step three obtain obtains sediment, uses deionized water washing and precipitating thing then;
Step 5, the sediment that step 4 is obtained is put into thermostatic drying chamber dries, and obtains powder;
Step 6, the powder that step 5 is obtained ground 10 minutes, then 200 ℃～800 ℃ temperature lower calcination 2～4 hours;
Step 7, the powder after the step 6 calcining was ground 10 minutes once more, obtain to suppress the tourmaline carried chromium powder agent of sulphate reduction.
The tourmaline carried chromium powder agent of inhibition sulphate of the present invention reduction is adopted is that particle diameter is that the tourmaline of nanometer or submicron order is as carrier, the characteristic that so not only has tourmaline, the characteristic that also has nano material, improve the surface area that contacts with the external world, increased the electric polarity and the piezoelectricity of tourmaline.The preparation method of the tourmaline carried chromium powder agent of inhibition sulphate reduction of the present invention adopts surface modification and ion exchange and solid-phase synthesis to upload chromium at tourmaline, effectively raises and carries the chromium amount, and then improved sterilization effects.
It is also active that the tourmaline carried chromium powder agent of inhibition sulphate reduction of the present invention can effectively suppress sulphate, make it no longer carry out the sulphate reduction and produce hydrogen sulfide gas, perhaps kill the sulfate reducing bacteria in the water, reach the purpose that reduces the harm that sulphate brings field produces and environment, simultaneously can also in the environment since the water body fouling that sulfate reducing bacteria causes etc. carry out environment remediation or improvement.
Description of drawings
Fig. 1 is preparation method's the flow chart of the tourmaline carried chromium powder agent of inhibition sulphate of the present invention reduction; Fig. 2 is AFM (AFM) schematic diagram of tourmaline; Fig. 3 is tourmaline ESEM (SEM) shape appearance figure; Fig. 4 is the SEM shape appearance figure of tourmaline carried chromium of the present invention; Fig. 5 is the infrared spectrogram of tourmaline and tourmaline carried chromium; Fig. 6 is the XRD figure of tourmaline; Fig. 7 is the XRD figure of tourmaline carried chromium; The XRD figure of tourmaline carried chromium when Fig. 8 is 650 ℃; Fig. 9 tourmaline chromium is to the rejection characteristic figure of the activity of sulfate reducing bacteria.
Embodiment
Embodiment one: the tourmaline carried chromium powder agent of the inhibition sulphate reduction of present embodiment is made up of tourmaline and chromium chloride, adopt surface modification and ion exchange and solid-phase synthesis that described chromium chloride is downloaded on institute's tourmaline, the particle diameter of described tourmaline is 50nm～800nm, and it is 0.01%～40% that described chromium chloride accounts for the tourmaline mass percent.
Referring to Fig. 9, the tourmaline carried chromium powder agent of the described inhibition sulphate reduction of present embodiment and the sample contrast that does not add bacteriostatic agent, the tourmaline carried chromium powder agent obvious suppression of inhibition sulphate of the present invention reduction the activity of sulfate reducing bacteria, sulfate reducing bacteria no longer utilizes sulphate, produce hydrogen sulfide odor, reached purpose of the present invention.
Embodiment two: the tourmaline carried chromium powder agent and the embodiment one described difference of the inhibition sulphate reduction of present embodiment are that it is 0.01%～12% that described chromium chloride accounts for the tourmaline mass percent.
Embodiment three: the tourmaline carried chromium powder agent and the embodiment one described difference of the inhibition sulphate reduction of present embodiment are that it is 12%～26% that described chromium chloride accounts for the tourmaline mass percent.
Embodiment four: the tourmaline carried chromium powder agent and the embodiment one described difference of the inhibition sulphate reduction of present embodiment are that it is 10% or 20% or 30% that described chromium chloride accounts for the tourmaline mass percent.
Embodiment five: the tourmaline carried chromium powder agent and the embodiment one described difference of the inhibition sulphate reduction of present embodiment are that the particle diameter of described tourmaline is 50nm～300nm.
Embodiment six: the tourmaline carried chromium powder agent and the embodiment one described difference of the inhibition sulphate reduction of present embodiment are that the particle diameter of described tourmaline is 300nm～550nm.
Embodiment seven: the tourmaline carried chromium powder agent and the embodiment one described difference of the inhibition sulphate reduction of present embodiment are that the particle diameter of described tourmaline is 550nm～800nm.
Embodiment eight: the tourmaline carried chromium powder agent and the embodiment one described difference of the inhibition sulphate reduction of present embodiment are that the particle diameter of described tourmaline is 60nm or 400nm or 700nm.
Embodiment nine: the preparation method of the tourmaline carried chromium powder agent of the inhibition sulphate reduction of present embodiment is:
Step 1, be that the tourmaline powder of 50nm～800nm joins in the deionized water, in magnetic stirring apparatus, at the uniform velocity stir, make the aaerosol solution of 0.1g/ml particle diameter;
Add the nitrate solution of 0.03mol/L in step 2, the aaerosol solution that in step 1, obtains, and to adjust the pH value be 4～8;
Step 3, in the mixed solution that step 2 obtains, add the chromium chloride solid of tourmaline powder mass percent 0.01%～40% described in the step 1, and add 1.5%～2.5% polyethylene glycol dispersant, stirred 4～5 hours;
The mixed solution that step 4, filtration step three obtain obtains sediment, uses deionized water washing and precipitating thing then;
Step 5, the sediment that step 4 is obtained is put into thermostatic drying chamber dries, and obtains powder;
Step 6, the powder that step 5 is obtained ground 10 minutes, then 200 ℃～800 ℃ temperature lower calcination 2～4 hours;
Step 7, the powder after the step 6 calcining was ground 10 minutes once more, obtain to suppress the tourmaline carried chromium powder agent of sulphate reduction.
In the step 4 in the present embodiment, can adopt the method for decompress filter that the mixed solution that step 3 obtains is filtered.
Embodiment ten: the method and the embodiment nine described differences of the tourmaline carried chromium powder agent of the inhibition sulphate reduction of present embodiment are, adopt 80 ℃～120 ℃ temperature to carry out freeze-day with constant temperature in step 5.
Embodiment 11: the method and the embodiment nine described differences of the tourmaline carried chromium powder agent of the inhibition sulphate reduction of present embodiment are, adopt 105 ℃ temperature to carry out freeze-day with constant temperature in step 5.
Embodiment 12: the method and the embodiment nine described differences of the tourmaline carried chromium powder agent of the inhibition sulphate reduction of present embodiment are that the calcining heat in step 6 is 200 ℃～400 ℃.
Embodiment 13: the method and the embodiment nine described differences of the tourmaline carried chromium powder agent of the inhibition sulphate reduction of present embodiment are that the calcining heat in step 6 is 400 ℃～600 ℃.
Embodiment 14: the method and the embodiment nine described differences of the tourmaline carried chromium powder agent of the inhibition sulphate reduction of present embodiment are that the calcining heat in step 6 is 600 ℃～800 ℃.
Embodiment 15: the method and the embodiment nine described differences of the tourmaline carried chromium powder agent of the inhibition sulphate reduction of present embodiment are that the calcining heat in step 6 is 300 ℃ or 500 ℃ or 700 ℃.

Claims (10)

1. suppress the tourmaline carried chromium powder agent of sulphate reduction, it is characterized in that it is made up of tourmaline and chromium chloride, adopt surface modification and ion exchange and solid-phase synthesis that chromium chloride is downloaded on the tourmaline, the particle diameter of described tourmaline is 50nm～800nm, and the mass percent that described chromium chloride accounts for tourmaline is 0.01%～40%.
2. the tourmaline carried chromium powder agent of inhibition sulphate reduction according to claim 1 is characterized in that it is 0.01%～12% that described chromium chloride accounts for the tourmaline mass percent.
3. the tourmaline carried chromium powder agent of inhibition sulphate reduction according to claim 1 is characterized in that it is 12%～26% that described chromium chloride accounts for the tourmaline mass percent.
4. the tourmaline carried chromium powder agent of inhibition sulphate reduction according to claim 1 is characterized in that it is 26%～40% that described chromium chloride accounts for the tourmaline mass percent.
5. the tourmaline carried chromium powder agent of inhibition sulphate reduction according to claim 1, the particle diameter that it is characterized in that described tourmaline is 50nm～300nm.
6. the tourmaline carried chromium powder agent of inhibition sulphate reduction according to claim 1, the particle diameter that it is characterized in that described tourmaline is 300nm～550nm.
7. the tourmaline carried chromium powder agent of inhibition sulphate reduction according to claim 1, the particle diameter that it is characterized in that described tourmaline is 550nm～800nm.
8. suppress the preparation method of the tourmaline carried chromium powder agent of sulphate reduction, it is characterized in that its concrete steps are:
Step 1, be that the tourmaline powder of 50nm～800nm joins in the deionized water, in magnetic stirring apparatus, at the uniform velocity stir, make the aaerosol solution of 0.1g/ml particle diameter;
Add the nitrate solution of 0.03mol/L in step 2, the aaerosol solution that in step 1, obtains, and to adjust the pH value be 4～8;
Step 3, in the mixed solution that step 2 obtains, add the chromium chloride solid of tourmaline powder mass percent 0.01%～40% described in the step 1, and add 1.5%～2.5% polyethylene glycol dispersant, stirred 4～5 hours;
The mixed solution that step 4, filtration step three obtain obtains sediment, uses deionized water washing and precipitating thing then;
Step 5, the sediment that step 4 is obtained is put into thermostatic drying chamber dries, and obtains powder;
Step 6, the powder that step 5 is obtained ground 10 minutes, then 200 ℃～800 ℃ temperature lower calcination 2～4 hours;
Step 7, the powder after the step 6 calcining was ground 10 minutes once more, obtain to suppress the tourmaline carried chromium powder agent of sulphate reduction.
9. the preparation method of the tourmaline carried chromium powder agent of inhibition sulphate reduction according to claim 8 is characterized in that adopting in step 5 80 ℃～120 ℃ temperature to carry out freeze-day with constant temperature.
10. the preparation method of the tourmaline carried chromium powder agent of inhibition sulphate reduction according to claim 8 is characterized in that the calcining heat in step 6 is 400 ℃～600 ℃.
CN2007100727622A 2007-09-06 2007-09-06 Tourmaline chromium-loaded inhibiting sulfate reducing bacteria powder and its preparation method Expired - Fee Related CN101142922B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN2007100727622A CN101142922B (en) 2007-09-06 2007-09-06 Tourmaline chromium-loaded inhibiting sulfate reducing bacteria powder and its preparation method

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN2007100727622A CN101142922B (en) 2007-09-06 2007-09-06 Tourmaline chromium-loaded inhibiting sulfate reducing bacteria powder and its preparation method

Publications (2)

Publication Number Publication Date
CN101142922A CN101142922A (en) 2008-03-19
CN101142922B true CN101142922B (en) 2011-02-02

Family

ID=39205794

Family Applications (1)

Application Number Title Priority Date Filing Date
CN2007100727622A Expired - Fee Related CN101142922B (en) 2007-09-06 2007-09-06 Tourmaline chromium-loaded inhibiting sulfate reducing bacteria powder and its preparation method

Country Status (1)

Country Link
CN (1) CN101142922B (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107720768B (en) * 2017-04-07 2019-12-27 中国地质大学（北京） Method for synthesizing tourmaline by solid phase method

Also Published As

Publication number Publication date
CN101142922A (en) 2008-03-19

Similar Documents

Publication Publication Date Title
Kumar et al. Quaternary magnetic BiOCl/g-C3N4/Cu2O/Fe3O4 nano-junction for visible light and solar powered degradation of sulfamethoxazole from aqueous environment
Wong et al. Wet chemically synthesized ZnO structures for photodegradation of pre-treated palm oil mill effluent and antibacterial activity
Mustafa et al. Synthesis and characterization of cupric oxide (CuO) nanoparticles and their application for the removal of dyes
Liu et al. Removal of algal blooms from freshwater by the coagulation–magnetic separation method
KR100836527B1 (en) Composition for removing red algae, green algae or diatom using porous nano sized titania photocatalyst, manufacturing method of said composition and red algae, green algae or diatom removing method using said composition
Jasrotia et al. Photocatalytic degradation of environmental pollutant using nickel and cerium ions substituted Co 0.6 Zn 0.4 Fe 2 O 4 nanoferrites
Ji et al. Modified mussel shell powder for microalgae immobilization to remove N and P from eutrophic wastewater
CN101343090B (en) Lanthanide series water treatment agent and method of preparing the same
CN100515986C (en) Bacterium-restraining haydite and preparation method thereof
CN105660705A (en) Composite sulfate reducing bacteria activity ecologic inhibitor and application thereof
Li et al. Synchronous algae and phosphorus removal by Ceramsite@ Fe2O3 (FC) via taking the algae as crystal nuclei of hydroxylapatite
Yue et al. Controllable biosynthesis of high-purity lead-sulfide (PbS) nanocrystals by regulating the concentration of polyethylene glycol in microbial system
CN102963983B (en) Vertical flow artificial wetland substrate modified based on LDHs (layered double hydroxides) coating film and preparation method of substrate
CN101142921A (en) Zeolite nanometer-zinc-oxide-loaded inorganic inhibiting sulfate reducing bacteria powder and its preparation method
Li et al. Low-Cost ceramic disk filters coated with Graphitic carbon nitride (g-C3N4) for drinking water disinfection and purification
Chandrapal et al. Enhancing the photocatalytic performance of g-C3N4 (GCN) via La–ZnO nanocomposite (Z-scheme mechanism) against toxic pharmaceutical pollutant
CN107986412B (en) Modified clay system for controlling harmful algal blooms in aquaculture water
Zhang et al. A novel strategy for efficient capture of intact harmful algal cells using Zinc oxide modified carbon nitride composites
Xia et al. Ceramsite sand and lime modified lake bottom sediments coupled with potassium ferrate pre-oxidation as emergency control of Microcystis aeruginosa blooms
Zhu et al. Antibacterial mechanism and enhancement of antibacterial activity under visible light in Er3+-doped BiOBr
CN101112199A (en) Sulfate reduction-resisting bacteria powder preparation adopting silver-carrying verdelite and method for preparing the same
CN101142922B (en) Tourmaline chromium-loaded inhibiting sulfate reducing bacteria powder and its preparation method
CN100515199C (en) Powder preparation for inhibiting sulfate reducing bacteria activity by adopting tourmaline carried cobalt
CN115634663A (en) Zr-Zn-Al LDH/graphene oxide composite material and preparation method and application thereof
Zhang et al. Fabrication of amorphous carbon-based zinc oxide for efficient capture of intact Microcystis aeruginosa: Lysis in sedimentation process

Legal Events

Date Code Title Description
C06 Publication
PB01 Publication
C10 Entry into substantive examination
SE01 Entry into force of request for substantive examination
C14 Grant of patent or utility model
GR01 Patent grant
C17 Cessation of patent right
CF01 Termination of patent right due to non-payment of annual fee

Granted publication date: 20110202

Termination date: 20110906