WATER TREATMENT AGENT

Abstract

The present invention is a water treatment agent containing (a) a polyalkylene oxide with a weight average molecular weight of 500,000 or more and (b) an inorganic flocculating agent.

Claims

1: A water treatment agent comprising: component (a): a polyalkylene oxide with a weight average molecular weight of 500,000 or more, and component (b): an inorganic flocculating agent.

2. (canceled)

3: The water treatment agent according to claim 1, wherein the component (b) is one or more inorganic flocculating agents selected from the group consisting of aluminum sulfate, sodium aluminate, polyaluminum chloride, aluminum oxide, aluminum hydroxide, iron(II) sulfate, iron(III) chloride, iron(III) sulfate, polyferric sulfate, sodium silicate, sodium sulfite and an aluminum alum.

4: The water treatment agent according to claim 1, wherein the agent comprises the component (a) in an amount of 0.1 parts by mass or more and 500 parts by mass or less relative to 1,000 parts by mass of the component (b).

5: The water treatment agent according to claim 1, wherein the agent further comprises a surfactant.

6: The water treatment agent according to claim 1, wherein the agent is of a multi-agent type including a first agent comprising the component (a) and a second agent comprising the component (b).

7: A method for purifying water comprising, adding component (a): a polyalkylene oxide with a weight average molecular weight of 500,000 or more, and component (b): an inorganic flocculating agent to water to be treated comprising water and polluting components.

8: The method for purifying water according to claim 7, wherein the component (a) is added such that a concentration of the component (a) in the water to be treated is 0.1 ppm or more and 500 ppm or less.

9: The method for purifying water according to claim 7, wherein the water to be treated comprises a surfactant together with the components (a) and (b).

10: The method for purifying water according to claim 9, wherein a concentration of the surfactant in the water to be treated is 0.1 ppm or more and 100,000 ppm or less.

11. (canceled)

12: The water treatment agent according to claim 1, wherein component (a) is a polyalkylene oxide including ethylene oxide as a polymerization unit.

13: The water treatment agent according to claim 1, wherein component (a) is polyethylene oxide.

14: The water treatment agent according to claim 1, wherein the weight average molecular weight of component (a) is 500,000 or more and 10,000,000 or less.

15: The water treatment agent according to claim 5, wherein the surfactant is one or more surfactants selected from the group consisting of anionic surfactants, nonionic surfactants, cationic surfactants, amphoteric surfactants and a water-soluble polymer with a molecular weight of less than 500,000.

16: The method for purifying water according to claim 7, wherein component (a) is a polyalkylene oxide including ethylene oxide as a polymerization unit.

17: The method for purifying water according to claim 7, wherein component (a) is polyethylene oxide.

18: The method for purifying water according to claim 7, wherein purified water is recovered.

19: The method for purifying water according to claim 7, wherein component (a) is added in an amount of 0.1 parts by mass or more and 500 parts by mass or less relative to 1,000 parts by mass of component (b).

Description

EXAMPLES

(1) Method for Preparing Polluted Water

[0075] 475 g of ion exchange water was placed in a 500-ml glass beaker. A cylindrical stirrer with a diameter of 11 mm and a length of 43 mm was placed therein, and the water was stirred for 1 minute on a magnetic stirrer (NISSIN stirrer SW-M120) with the scale set to 4. 0.5 g of soil (Kanuma soil which was ground in a mixer of Hosokawa Micron Co., Ltd.) was added and stirred for 30 seconds. In the evaluation described below, the amount of polluted water after adding component (a) or the like (also referred to as polluted water for evaluation) was adjusted to be 500 g (about 500 ml). Taking this into account, any of the following surfactants was added such that the concentration in 500 g of the polluted water for evaluation was a value shown in Table 1 or 2, and stirred for 30 seconds to prepare polluted water as water to be treated.

[0076] Surfactant

LAS: sodium lauryl benzene sulfonate, NEOPELEX G-15 (manufactured by Kao Corporation)
AS: sodium lauryl sulfate, EMAL 10G (manufactured by Kao Corporation)
AES: sodium polyoxyethylene lauryl ether sulfate, EMAL 270J (manufactured by Kao Corporation)
Sodium oleate: FUJIFILM Wako Pure Chemical Corporation Polyoxyethylene lauryl ether: EMULGEN 108 (manufactured by Kao Corporation)

(2) Evaluation

[0077] The prepared polluted water was used as water to be treated to evaluate a water purification effect.

[0078] The polluted water was set on the magnetic stirrer (NISSIN stirrer SW-M120), and while stirring it with the scale set to 4, component (b) was added such that the concentration in the polluted water for evaluation was a value shown in Table 1 or 2, and 30 seconds later, sodium hydroxide was added to adjust the pH to 7. Further 30 seconds later, an aqueous solution prepared in advance from ion exchange water to contain component (a) or (a′) in a concentration of 1,000 ppm was added such that the concentration of component (a) or (a′) in the polluted water for evaluation was a value shown in Table 1 or 2, and ion exchange water was finally added such that the total liquid volume was 500 g and stirred for 300 seconds in total to obtain the polluted water for evaluation. After stirring, it was left for 1 hour in a room whose temperature was adjusted to 25° C. The polluted water for evaluation underwent decantation into a separately prepared 500-ml glass beaker so as to prevent flocculates from entering. The amount of water which could be recovered at that time was taken as N g, and a water recovery rate was calculated by the following formula. The results are shown in Tables 1 and 2. The larger the water recovery rate value is, the superior the water purification effect is.

Water recovery rate (%)=N/500×100

TABLE-US-00001 TABLE 1 Example 1-1 1-2 1-3 1-4 1-5 1-6 Concentration Polluting Surfactant LAS 200 200 200 200 200 in component Mud 1000 1000 1000 1000 1000 1000 polluted Water (a) PEO 10 10 1 20 water treatment (7,000,000) for agent PEO 10 evaluation (4,500,000) (ppm) PEO 10 (2,000,000) PEO (500,000) (a′) PEO (300,000) AAm (5,000,000) Crosslinked AA (b) Aluminum sulfate 1000 1000 1000 1000 1000 1000 Ferric sulfate Polyaluminum chloride Polyferric sulfate pH of polluted water for 7 7 7 7 7 7 evaluation.sup.*1 Water recovery rate (%) 87 98 91 99 95 93 Example 1-7 1-8 1-9 1-10 1-11 1-12 Concentration Polluting Surfactant LAS 200 200 200 200 200 200 in component Mud 1000 1000 1000 1000 1000 1000 polluted Water (a) PEO 10 10 10 10 10 water treatment (7,000,000) for agent PEO evaluation (4,500,000) (ppm) PEO (2,000,000) PEO 10 (500,000) (a′) PEO (300,000) AAm (5,000,000) Crosslinked AA (b) Aluminum sulfate 1000 100 10000 Ferric sulfate 1000 Polyaluminum 1000 chloride Polyferric sulfate 1000 pH of polluted water for 7 7 7 7 7 7 evaluation.sup.*1 Water recovery rate (%) 91 90 99 95 96 94 Comparative example 1-1 1-2 1-3 1-4 1-5 Concentration Polluting Surfactant LAS 200 200 200 200 200 in component Mud 1000 1000 1000 1000 1000 polluted Water (a) PEO 10 water treatment (7,000,000) for agent PEO evaluation (4,500,000) (ppm) PEO (2,000,000) PEO (500,000) (a′) PEO 10 (300,000) AAm 10 (5,000,000) Crosslinked AA 10 (b) Aluminum sulfate 1000 1000 1000 1000 Ferric sulfate Polyaluminum chloride Polyferric sulfate pH of polluted water for 7 7 7 7 7 evaluation.sup.*1 Water recovery rate (%) 82 83 80 0 71 .sup.*1adjusted with sodium hydroxide

TABLE-US-00002 TABLE 2 Example 2-1 2-2 2-3 2-4 2-5 2-6 2-7 Concentration Polluting Surfactant LAS 200 100 1000 in component AS 200 polluted AES 200 water Sodium oleate 200 for Polyoxyethylene 200 evaluation lauryl ether (ppm) Mud 1000 1000 1000 1000 1000 1000 1000 Water (a) PEO (7,000,000) 10 10 10 10 10 10 10 treatment (b) Aluminum sulfate 1000 1000 1000 1000 1000 1000 1000 agent pH of polluted water at treatment.sup.*1 7 7 7 7 7 7 7 Water recovery rate (%) 98 98 90 96 95 95 91 .sup.*1adjusted with sodium hydroxide

[0079] Components in the tables are the following. Weight average molecular weights of components (a) and (a′) are shown in parentheses.

Component (a)

[0080] PEO (7,000,000): polyethylene oxide, PEO-27, Sumitomo Seika Chemicals Company, Limited, spinnability

[0081] PEO (4,500,000): polyethylene oxide, PEO-18, Sumitomo Seika Chemicals Company, Limited, spinnability

[0082] PEO (2,000,000): Polyethylene Glycol 2,000,000, FUJIFILM Wako Pure Chemical Corporation

[0083] PEO (500,000): polyethylene oxide, PEO-2, Sumitomo Seika Chemicals Company, Limited, spinnability

Component (a′)

[0084] PEO (300,000): polyethylene oxide, PEO-1, Sumitomo Seika Chemicals Company, Limited

[0085] AAm (5,000,000): polyacrylamide, FUJIFILM Wako Pure Chemical Corporation

[0086] Crosslinked AA: CARBOPOL 940, The Lubrizol Corporation Component (b)

[0087] Aluminum sulfate: aluminum sulfate (anhydrous), TAIMEI CHEMICALS CO., LTD.

[0088] Ferric sulfate: iron(III) sulfate (anhydrous), FUJIFILM Wako Pure Chemical Corporation

[0089] Polyaluminum chloride: polyaluminum chloride, TAIMEI CHEMICALS CO., LTD.

[0090] Polyferric sulfate: polyferric sulfate, TAIKI CHEMICAL INDUSTRIES CO., LTD.

pH Adjuster

[0091] Sodium hydroxide: FUJIFILM Wako Pure Chemical Corporation