US4097376A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for the purification of industrial effluents
Assignee: BASF Corp
•
Filing: 1977-02-24
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Granted: 1978-06-27
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Expires: 1997-02-24
Abstract
Abstract A novel process for purifying industrial effluents which comprises bringing said effluents into contact with cellulosic absorbent which has been pretreated with precipitants.
Inventors
- 👤 Hans Wegmuller
- 👤 Jaroslav Haase
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 10:32
CPC Classifications
C; C02; C02F; C02F1/00; C02F1/52; C02F1/5263; C02F1/28; C02F1/286; C02F1/54
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
45 words
A process for purifying industrial effluents containing residual substances comprising dyestuffs, optical brighteners, dyeing auxiliaries, detergents, tanning agents or mixtures thereof, which comprises bringing said effluents into contact with a cellulosic absorbent pretreated with (a) a water soluble basic aminoplast, and (b) a polyanionic polymer.
Claim 2
Dependent Claim
45 words
A process for purifying industrial effluents containing residual substances comprising dyestuffs, optical brighteners, dyeing auxiliaries, detergents, tanning agents or mixtures thereof, which comprises bringing said effluents into contact with a cellulosic absorbent pretreated with (a) a water soluble basic aminoplast, and (b) a polyanionic polymer.
Claim 3
Dependent Claim
39 words
A process according to claim 1, wherein the water-soluble basic aminoplast is a condensation product of formaldehyde, dicyandiamide and urea, or of formaldehyde, dicyandiamide and an alkylenepolyamine with 2 to 12 carbon atoms and 2 to 5 amino groups.
Claim 4
Dependent Claim
22 words
A process according to claim 2, wherein the poly-anionic polymer is a homopolymer or copolymer of an aliphatic, α,β-ethylenically unsaturated carboxylic acid.
Claim 5
Dependent Claim
16 words
A process according to claim 3, wherein the water-soluble basic aminoplast is a formaldehyde-dicyandiamideethylenediamine condensation product.
Claim 6
Dependent Claim
27 words
A process according to claim 4, wherein the polyanionic polymer is a water-soluble homopolymer of acrylic or methacrylic acid with a molecular weight of 20,000 to 1,000,000.
Claim 7
Dependent Claim
29 words
A process according to claim 1, wherein the cellulosic absorbent is pretreated with a mixture of said basic aminoplast and polyanionic polymer and a salt of a polyvalent metal.
Claim 8
Dependent Claim
36 words
A process according to claim 6, wherein the cellulosic absorbent is pretreated with a mixture of said basic aminoplast, polyanionic polymer and salt of a polyvalent metal in the presence of an inorganic or organic base.
Claim 9
Dependent Claim
17 words
A process according to claim 1, wherein the purification is carried out at 10° to 150° C.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-06-26 | 1981-12-26 | 1982-06-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-06-26 | 1985-12-26 | 1986-06-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-06-26 | 1989-12-26 | 1990-06-27 | $7700.00 | Window Closed / Lapsed |