The catalytic cracking of methane over nickel gauze is proposed as an attractive alternative for the production of CO-free hydrogen. The catalyst deactivates due to intensive coke deposition. Therefore, the reactor was operated periodically with the reaction followed by the catalyst regeneration by burning of coke in oxidative atmosphere. The optimal reaction performance was found to consist of...

a study was made of the coking of a commercial fresh sulfide ni-mo/al2o3 catalyst in a fixed-bed reactor. the catalyst was coked using different coke precursors in the gas oil under accelerated conditions at temperatures of 400 to 450°c to yield different deactivated catalysts containing 2-20 wt% c. two cases were studied; crushed catalyst without diffusional resistance and extruded pellets wit...

The catalytic activity of large zeolite H-ZSM-5 crystals in methanol (MTO) and ethanol-to-olefins (ETO) conversions was investigated and, using operando UV/Vis measurements, the catalytic activity and deactivation was correlated with the formation of coke. These findings were related to in situ single crystal UV/Vis and confocal fluorescence micro-spectroscopy, allowing the observation of the s...

To evaluate the association between an indicator of carcinogen exposure (peripheral blood leukocyte DNA adducts of polycyclic aromatic hydrocarbons) and an early indicator of neoplastic transformation (sputum epithelial cell membrane antigens binding by monoclonal antibodies against small cell lung cancer and against nonsmall cell lung cancer), a survey of 350 coke-oven workers and 100 unexpose...

In this study the corroding and/or tarnishing implications of coke, a fizzy soft drink, tea and coffee to the eta prime phase plastic amalgam surface following the filling were evaluated. Thirty six acrylic blocks were prepared which each one was having 5 mm in diameter and 1 mm in depth welts where condensed with amalgam. Those blocks were divided into six groups. The groups were coffee, tea, ...

Catalysts and catalyst binders are significant portions of the cost of microbial fuel cell (MFC) cathodes. Many materials have been tested as aqueous cathodes, but air-cathodes are needed to avoid energy demands for water aeration. Packed-bed air-cathodes were constructed without expensive binders or diffusion layers using four inexpensive carbon-based materials. Cathodes made from activated ca...

Quality of petroleum cokes and coals has been evaluated for export specifications required in use of specialty products and utility bels. Various green and calcined cokes, produced at refineries m California, and coals for shipment are sampled at California and national ports, and analyzed by using ASTM Methods. Quality analysis reports include: proximate and ultimate analyses, metals, tu, dens...

This paper describes a case study of improving the asset performance of ethylene cracking furnaces through energy saving by Yokogawa’s Asset Performance Diagnostics service, one of the services of Plant Asset Effectiveness Optimization Services, InsightSuiteAE. During regular maintenance of ethylene cracking furnaces, steam and air are supplied to tubes for decoking to burn and remove coke whic...

Diesel fuels of 50 and 15 ppm of sulfur content were produced in a pilot plant by upgrading light catalytic cracking gas oil (LCO) during 10 weeks of continuous operation. The end-of-run catalysts were characterized before and after soluble coke extraction by CH2Cl2. The cokes were characterized by CNMR, TPO, GC-MS, and elemental analysis. Catalyst surfaces were characterized by XPS, CO adsorpt...