Catalytic adsorbents obtained from municipal sludges, industrial sludges, compost and tobacco waste and process for their production

• US 9,808,761 B2
• Filed: 04/27/2016
• Issued: 11/07/2017
• Est. Priority Date: 09/08/2005
• Status: Expired due to Fees

• Current Assignee: City College of New York
• Original Assignee: City College of New York
• Inventors: Bandosz, Teresa J.
• Primary Examiner(s): HENDRICKSON, STUART L
• Application Number:
  US15/139,843
• Publication Number:
  US 20160236146A1
• Time in Patent Office: 559 Days
• CPC Class Codes: B01D 2253/102 Carbon
• CPC Class Codes: B01D 2253/104 Alumina
• CPC Class Codes: B01D 2253/112 Metals or metal compounds not provided for in B01D2253/104 or B01D2253/106
• CPC Class Codes: B01D 2253/308 Pore size
• CPC Class Codes: B01D 2253/311 Porosity, e.g. pore volume
• CPC Class Codes: B01D 2255/20738 Iron
• CPC Class Codes: B01D 2255/20761 Copper
• CPC Class Codes: B01D 2255/20792 Zinc
• CPC Class Codes: B01D 2255/2092 Aluminium
• CPC Class Codes: B01D 2255/405 Spinels
• CPC Class Codes: B01D 2257/302 Sulfur oxides
• CPC Class Codes: B01D 2257/304 Hydrogen sulfide
• CPC Class Codes: B01D 2257/408 Cyanides, e.g. hydrogen cyanide (HCH)
• CPC Class Codes: B01D 2259/40088 by heating
• CPC Class Codes: B01D 53/02 by adsorption, e.g. preparative gas chromatography solid sorbent compositions B01J20/00, preparation of inorganic compounds or elements C01
• CPC Class Codes: B01D 53/04 with stationary adsorbents B01D53/025 takes precedence
• CPC Class Codes: B01D 53/508 by treating the gases with solids
• CPC Class Codes: B01D 53/52 Hydrogen sulfide
• CPC Class Codes: B01D 53/54 Nitrogen compounds
• CPC Class Codes: B01D 53/565 by treating the gases with solids
• CPC Class Codes: B01D 53/8612 : Hydrogen sulfide
• CPC Class Codes: B01J 20/0229 : Compounds of Fe
• CPC Class Codes: B01J 20/0237 : Compounds of Cu
• CPC Class Codes: B01J 20/0244 : Compounds of Zn
• CPC Class Codes: B01J 20/041 : Oxides or hydroxides
• CPC Class Codes: B01J 20/06 : comprising oxides or hydroxides of metals not provided for in group B01J20/04
• CPC Class Codes: B01J 20/08 : comprising aluminium oxide or hydroxide; comprising bauxite
• CPC Class Codes: B01J 20/103 : comprising silica
• CPC Class Codes: B01J 20/20 : comprising free carbon; comprising carbon obtained by carbonising processes
• CPC Class Codes: B01J 20/22 : comprising organic material
• CPC Class Codes: B01J 20/24 : Naturally occurring macromolecular compounds, e.g. humic acids or their derivatives
• CPC Class Codes: B01J 20/28059 : being less than 100 m2/g
• CPC Class Codes: B01J 20/28061 : being in the range 100-500 m2/g
• CPC Class Codes: B01J 20/28069 : Pore volume, e.g. total pore volume, mesopore volume, micropore volume
• CPC Class Codes: B01J 20/2808 : being less than 2 nm, i.e. micropores or nanopores
• CPC Class Codes: B01J 20/3078 : Thermal treatment, e.g. calcining or pyrolizing
• CPC Class Codes: B01J 20/3416 : of sorbents or filter aids comprising free carbon, e.g. activated carbon
• CPC Class Codes: B01J 20/3425 : of sorbents or filter aids comprising organic materials
• CPC Class Codes: B01J 20/3433 : of sorbents or filter aids other than those covered by B01J20/3408 - B01J20/3425
• CPC Class Codes: B01J 20/3483 : by thermal treatment not covered by groups B01J20/3441 - B01J20/3475, e.g. by heating or cooling
• CPC Class Codes: B01J 21/02 : Boron or aluminium; Oxides or hydroxides thereof
• CPC Class Codes: B01J 2220/42 : Materials comprising a mixture of inorganic materials materials coated or impregnated on a carrier B01J20/32
• CPC Class Codes: B01J 2220/4887 : Residues, wastes, e.g. garbage, municipal or industrial sludges, compost, animal manure; fly-ashes
• CPC Class Codes: B01J 23/005 : Spinels
• CPC Class Codes: B01J 23/06 : of zinc, cadmium or mercury
• CPC Class Codes: B01J 23/72 : Copper
• CPC Class Codes: B01J 23/745 : Iron
• CPC Class Codes: B01J 31/26 : containing in addition, inorganic metal compounds not provided for in groups B01J31/02 - B01J31/24

Abstract

Industrial waste derived adsorbents were obtained by pyrolysis of sewage sludge, metal sludge, waste oil sludge and tobacco waste in some combination. The materials were used as media to remove hydrogen sulfide at room temperature in the presence of moisture. The initial and exhausted adsorbents after the breakthrough tests were characterized using sorption of nitrogen, thermal analysis, XRD, ICP, and surface pH measurements. Mixing tobacco and sludges result in a strong synergy enhancing the catalytic properties of adsorbents. During pyrolysis new mineral phases are formed as a result of solid state reaction between the components of the sludges. High temperature of pyrolysis is beneficial for the adsorbents due to the enhanced activation of carbonaceous phase and chemical stabilization of inorganic phase. Samples obtained at low temperature are sensitive to water, which deactivates their catalytic centers.

Claims

1. A method of removing acidic gases from wet air streams comprising putting an adsorbent comprising

a) a waste material composition, comprising:

one of compost or compost materials and sludge;

(1) wherein the compost is one of tobacco waste, waste paper, wood char or a combination thereof;

(2) wherein the sludge is at least one of waste oil, metal, or municipal sludge;

(ii) 20-30% porous organic carbon with incorporated organic nitrogen species; and

(iii) 70-80% inorganic matter;

b) adsorbent characteristics, wherein;

(i) the adsorbent is capable of adsorbing up to about 30% of the adsorbent'"'"'s weight in hydrogen sulfide;

(ii) a surface area of the adsorbent is 10-200 m²/g; and

(iii) the pH of the adsorbent is between 7-12;

in contact with the wet air stream and allowing the adsorbent to adsorb the acidic gases.

2. The process of claim 1, wherein the acidic gases are one or more of hydrogen sulfide, sulfur dioxide, hydrogen cyanide, and nitrogen dioxide.

3. The process of claim 1, wherein the acidic gas is hydrogen sulfide which reacts within organic matter to be oxidized to sulfur dioxide or elemental sulfur and salt forms thereof.

4. The process of claim 1, wherein the wet air stream is effluent from a sewage treatment plant, gaseous fuel, or gases from hydrothermal vents.

5. A method of removing acidic gases from wet air streams comprising the steps of:

a) composting tobacco waste, waste paper, wood char or a combination thereof;

b) thermally drying at least one of dewatered waste oil or metal sludge;

c) mixing the dried sludge and the compost;

d) pyrolyzing the mixture at temperatures between 600°

C. and 1100°

C., comprising the steps of;

(i) heating the mixture between 5 and 10°

C./minute;

(ii) holding the heated mixture between 60 and 90 minutes; and

(e) forming an adsorbent, wherein;

(i) the adsorbent is capable of adsorbing up to about 30% of the adsorbent'"'"'s weight in hydrogen sulfide;

(ii) a surface area of the adsorbent is 10-200 m²/g; and

(iii) the pH of the adsorbent is between 7-12;

(f) putting said adsorbent in contact with the wet air stream; and

(g) allowing the adsorbent to adsorb the acidic gases.

6. The process of claim 5, wherein the acidic gases are one or more of hydrogen sulfide, sulfur dioxide, hydrogen cyanide, and nitrogen dioxide.

7. The process of claim 5, wherein the temperature of pyrolysis is between 800 and 1000°

C.

8. The process of claim 7, wherein the temperature of pyrolysis is between 900 and 1000°

C.

9. The process of claim 5, wherein the temperature of pyrolysis is between 600 and 900°

C. and the adsorbent is further treated with 15-20% HCl.

10. The process of claim 9, wherein the temperature of pyrolysis is between 800 and 900°

C.

11. The process of claim 5, wherein the adsorbent may be regenerated by heating to 300-500°

C. to remove elemental sulfur and sulfur dioxide.