|
| Source of sludge | Modifier | Synthetical method | Treated compounds | Synthetical conditions | Results | Reference |
|
| Yanzhuang sewage treatment plant in high-tech zone | Coke powder | Chemical activation method (coupling of acid and salt : sulfuric acid, zinc chloride) | Ammonia nitrogen, chromaticity | Activation temperature: 750°C; activation time: 2 h; mass ratio of sludge to blue charcoal: 5 : 2, V (sludge-blue charcoal) : V (activator) = 1 : 2.5 | The SBAC pore structure was dominated by the middle hole. The BET area was small. The preparation of SBAC contained many types of hydrocarbon and oxygen-containing functional groups. | [72] |
| A sewage treatment plant in Songjiang district | Loading metal Co and Fe | Hydrothermal method | Dye wastewater: Congo red | Hydrothermal time: 3 h; temperature: 180°C; and ultrasonic time: 10 min | The surface and internal hole of SBAC occurring after adding nanocobalt, which increased the BET; SBAC had good magnetic separation performance; the separation of solution and adsorption material was easy to separate, which were conducive to the recovery and utilization of SBAC. | [74] |
| Ningbo APP Asia pulp paper deinking sludge | Nothing | Chemical activation method (acid activation : phosphoric activation) | Modeling iodine solution and methylene blue as standard of evaluation | Activation time: 90 min; activation temperature: 450°C; mass impregnation ratio of sludge to phosphoric acid solution is 1 : 1.3; phosphate concentration : 70% | The BET of SBAC was large and contained a large number of hydroxyl groups. The middle hole was developed and stable. The microcrystal was irregular and the crystallization degree was high. | [75] |
| A sewage treatment plant in Zhejiang province | Loading manganese and iron oxide | Chemical activation method (salt activation: ZnCl2 | Effluent of biochemical treatment of coal gas wastewater | 5 mol/L ZnCl2 solution; impregnated time: 24 h; mass of solid : liquid ratio: 1 : 3; activation temperature: 600°C and time: 3 h | Metal manganese and iron oxide were loaded to SBAC. The catalytic process was dominated by the indirect oxidation reaction of hydroxyl radical and the synergistic effect of various oxidation reactions. | [76] |
| Xi’an fourth sewage treatment plant | Wood chips | Chemical activation method (salt activation: ZnCl2) | High-concentration coal wastewater | Activation temperature: 650°C; activation time: 30 min; solid : liquid ratio: 1 : 1.5 | The wood chip SBAC had rich tubular pore structure, and the pore arrangement was relatively uniform and orderly, which mainly was the middle pore. The wood chip increased the carbon content of SBAC and greatly increased the area of BET and the total pore volume. | [24] |
| Sewage sludge in a paper mill in Zhejiang province | Loading iron and copper | Chemical activation method (acid activation: nitric acid, hydrochloric acid) | Dye wastewater: synthetic methylene blue | Pyrolysis temperature: 800°C and time: 2 h; activation conditions: 5 mol/L sulfuric acid (solid : liquid ratio : 0.1) | The SBAC-based catalytic carrier was loaded with iron and copper binary metal as a nonhomogeneous Fenton catalyst. The pore structure was developed and the surface functional groups were rich, which mainly had hydroxyl radical reaction. The pH range of catalytic carrier reaction system was greatly expanded. | [77] |
| A sewage treatment plant in Yan’an | Peanut shells, wood chips, and walnut shells | Chemical activation method (alkali activation: KOH) | Oil-containing wastewater | Activation temperature: 350°C; activation time: 40 min; 0.5 mol/L KOH infusion, mass ratio of peanut shell quality to sludge: 20% | In the preparation of peanut shell SBAC, the activation of KOH and the high temperature in carbonization process played an important role in the making of holes, so that it had better adsorption capacity. The surface was rough and had a porous structure, which also had the phenolic hydroxyl group, ether bond, lactone bond, and so on. | [25] |
| A factory waste paper deinking sludge in Rizhao | Wood powder | Chemical activation method (alkali activation: KOH) | Bleaching wastewater from alkali extraction in paper mill | Mass ratio of wood powder to sludge: 20%; ratio of carbon to alkali 1 : 1; activation temperature: 675°C; the activation time: 75 min | In the activation process, the surface of the carbonized material was formed into holes and scattered short bars. The pores of the cross-section were dense and honeycombed. Most of the holes were micropores; some of which were porous, with a relatively developed pore structure and strong adsorption capacity. | [78] |
| Low organic matter dehydration sludge of a sewage treatment plant in Chongqing | Nothing | Chemical activation (acid activation: phosphoric acid); microwave activation method | Methyl-purple dye wastewater | Soaked time: 24 h; microwave power: 464 W; microwave activation time: 4 min | SBAC had a tube-shaped hole and its pore diameter was wider. SBAC had acidic surface functional groups such as the hydroxyl group and carboxyl group, which were beneficial to the adsorption of alkaline dyes. | [79] |
| A petrochemical refinery dries up the remaining sludge | Datong bituminous coal | Chemical activation method (salt activation: ZnCl2) | Phenol | Activation temperature: 550°C; activation time: 30 min; mass ratio of ZnCl2 solution and sludge: 2 : 1 | The surface groups were mainly acidic groups, while the alkaline groups were less, and the choice of zinc chloride as activator was beneficial to the formation of acidic groups. | [80] |
| Shanghai east district sewage treatment plant | Loading manganese | Chemical activation method (acid and salt activation: ZnCl2, H2SO4) | Oxalic acid wastewater | Volume ratio of 3 mol/L H2SO4 to 3 mol/L ZnCl2 solution: 1 : 2; heating rate: 10°C/min; activation temperature: 550°C; activation time: 60 min | The reaction mechanism of hydroxyl radical was consistent with the SBAC-based catalytic ozone process. Oxalic acid was adsorbed on the surface of the catalyst and reacted with the ozone molecules and hydroxyl radicals produced by the ozone molecules. The free radicals formed on the surface of the catalyst diffused into the solution and reacted with oxalic acid. | [81] |
| Chengdu municipal sewage treatment plant | Iron additive
铁细 | Chemical activation method (salt activation: ZnCl2) | Modeling iodine solution | Pyrolysis temperature: 400°C; pyrolysis time: 70 min | Iron compounds could promote the decomposition of carbon organic compounds that were difficult to convert, and its own decomposition could leave pores and regulated the structure of the activated carbon pore. When the additive was small, the dispersion was uneven and the local overheat was burnt into a large hole. While more was added, the catalytic activity could be increased to enhance the catalytic action, to form a micropore and enlarge the original microhole, increasing the adsorption iodine value. | [55] |
| Sewage treatment plant of Shanxi University of Science and Technology | Nothing | Chemical activation method (salt activation: ZnCl2) | Acid red G solution | ZnCl2 concentration of 30%; mass ratio of sludge to ZnCl2 solution: 1 : 2; carbonization temperature: 500°C; carbonization time: 1.5 h | The SBAC surface was rough, with more porous structures and irregular porous structures. Acid red G was adsorbed on SBAC as single-layer adsorption; the regenerated SBAC had a good adsorption capacity for acid red G, and the regeneration ability was good. The heat treatment method was better than alkali treatment. | [82] |
| A sewage treatment plant in Lu’an city | Nothing | Chemical activation method (alkali activation: KOH) | Electroplating wastewater | Mass ratio of sludge to KOH solution: 1 : 3; activator concentration: 40%; activation temperature: 500°C; activation time: 60 min | The control of activation temperature and time could make SBAC compact microporous. KOH had a hole-forming effect on the sludge, and when the hole was saturated, too many activators could cause the channel to collapse or clog up and destroy the formed channel structure, resulting in the decrease of adsorption performance. | [83] |
| Sludge from sewage and of a refinery in Shijiazhuang 炼油厂 | Noting | Chemical activation method (salt activation: ZnCl2) | Modeling iodine solution | Mass ratio of sludge to ZnCl2 solution: 1 : 3; carbonization time: 1 h | SBAC presented an irregular porous structure, with more transition holes extending into the interior, and it had the properties of easy adsorption of macromolecular organic matter. The process of chemical activation and pyrolysis had a good effect on the hole making, which made the sludge have better adsorption capacity. | [84] |
| Beijing Xiaohongmen sewage treatment plant | Corn kernel | Direct pyrolysis and modification with (NH4)2S2O8 acid and NaOH alkali | Para-chlorobenzoic acid (p-CBA) solution | 30% ZnCl2 solution; activation time: 1 h; activation temperature: 600°C activation | NaOH-modified surface had a rich alkaline functional group, and the removal p-cba by SBAC-based catalytic ozone oxidation was enhanced. (NH4) 2S2O8 destroyed the pore wall structure of activated carbon, so that the micropore and middle hole were expanded into large holes, resulting in the decrease in the level of BET. | [85] |
|
