Ozone Catalyst Manufacturing: Pore Forming, Sintering and the Strength Trade-off
Ozone cost per kilogram of chemical oxygen demand removed is set by the catalyst long before it is set by the generator. A material with more usable surface converts more of the dosed ozone into hydroxyl radicals, and a material that crumbles in the bed converts almost none of it after the first backwash. Manufacturing therefore has to solve two problems at once, and the interesting part of the technology is how it does that.
The material problem behind the ozone bill
Ozone catalysts are the core material of advanced oxidation and carry the load in hard industrial wastewater. The SINOKLE series was developed through sustained technology R&D and is held under independent intellectual property. The design target is not maximum surface area in the abstract but maximum useful surface that survives years of service, because utilisation rate, treatment efficiency, operating cost and the completeness of organic degradation all trace back to it.
Carrier chemistry and multi-metal active sites
The series uses a heterogeneous catalytic system with modified activated alumina as the carrier and a multi-metal synergistic mechanism for oxidation. Active components include copper, manganese, cobalt and rare-earth elements, with precious metal components introduced to create multi-active-site synergy. The result is a material with strong electron transfer capability that lowers the activation energy of ozone decomposition and raises the yield of hydroxyl radicals. Synergy here is not a marketing word: the metal components interact electronically and geometrically, so activity and selectivity both improve beyond what the individual oxides deliver, and the precious metal addition reconfigures the active sites in a way that also improves resistance to poisoning.
Pore forming versus mechanical strength
High-porosity microporous forming brings the specific surface area to 250-300 m²/g, well above the 50-100 m²/g typical of competing products, and that porous structure supplies the contact interface the reaction needs. Surface chemistry is modified further by atomic deposition, a super-hydrophilic treatment that brings the surface contact angle to ≤10° and keeps fouling and plugging from taking hold, so long-term operation stays stable.
The conventional conflict is that porosity and strength pull in opposite directions. Water-soluble porogens combined with a sacrificial metal template route resolve it: pore size distribution is controlled by adjusting porogen type and concentration, so a high specific surface area is retained while mechanical strength stays usable. Measured on the finished product, strength reaches 150 N per granule, annual wear is 0.13%, and service life exceeds 5 years. Acid and alkali tolerance covers pH ≤3 and pH ≥12, which is what allows the same material to run on strongly acidic and strongly alkaline streams without a change of grade.
Sintering schedule
Firing decides whether the active components end up where they were placed. Multi-stage precisely controlled temperature sintering optimises the microstructure by controlling temperature at each stage, which distributes the active components uniformly and builds a stable crystal structure while avoiding the pore collapse that over-sintering causes. The gain shows up in catalytic performance: absolute chemical oxygen demand removal per unit of ozone reaches 1.1-1.5 gO₃/gCOD, and ozone utilisation runs more than 20% above conventional technology.
Three wastewaters, three sets of numbers
An over-sintered batch announces itself in service rather than on the datasheet: the specific surface area reads acceptable on a fresh sample, then the bed pressure climbs, backwash frequency rises and ozone consumption per unit of chemical oxygen demand drifts upward within a few months. Holding the firing curve inside a narrow window is what keeps a delivered lot behaving like the pilot lot, and it is the part of the process that is hardest to copy from a specification sheet.
Oily wastewater is the best-known duty, but the harder evidence comes from three other applications. A landfill site in Fuzhou treated mature leachate with an influent chemical oxygen demand of about 3,000 mg/L; after 30 minutes the figure dropped below 200 mg/L and biodegradability improved markedly. A project in Zhangzhou ran on influent salinity above 30,000 mg/L, a range where conventional biological methods stop working, and still brought effluent chemical oxygen demand below 60 mg/L with colour down to below 5. A pharmaceutical enterprise in Inner Mongolia started from a wastewater chemical oxygen demand of several thousand mg/L, ran 45 minutes of ozone catalytic oxidation, and finished below 200 mg/L with the B/C ratio up from 0.1 to 0.37.
What the development effort actually bought
Three lines of work - multi-metal synergistic catalysis, super-hydrophilic modification and precision pore forming - addressed the four weaknesses that hold conventional ozone oxidation back: low utilisation rate, modest treatment efficiency, high operating cost and incomplete organic degradation. The technology carries a number of international and national patent authorisations, and the practical consequence is a material that can be specified by performance rather than by trial.
Module design adapts to projects of different scale, and an intelligent control system allows precise operational regulation. That combination matters more than any single figure on the datasheet, because the cost of ozone treatment is decided in service, on streams that change with the crude slate, the season and the production schedule.