• Journal of Korean Society of Environmental Engineers
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• v.31 no.8
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• pp.679-689
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• 2009

Light olefins are very important hydrocarbons widely used as the raw materials of the most petrochemicals including plastics and medicines. In addition, the nation's olefin production capacity is regarded as one of the key indicators to predict the nation's economic scale and growth. Steam cracking of naphtha (or called "NCC (Naphtha Cracking Center) technology"), the traditional process to produce light olefins, is one of the most consuming energy processes among the chemical industries. Therefore, this process causes tremendous $CO_2$ emission. To reduce the energy consumption and $CO_2$ emission from NCC process, the present paper, firstly, investigates and analyses some alternative technologies which can be potentially substituted for traditional process. Secondly, applying the alternative technologies to NCC process, their effects such as energy savings, $CO_2$ emission reduction and CER (Certified Emission Reduction) were estimated. It is found that the advanced NCC process can reduce approximately 35% of SEC (Specific Energy Consumption) of traditional NCC process. This effect can lead to the reduction of 3.3 million tons of $CO_2$ and the acquisition of the 128 billion won of CER per year. Catalytic cracking of naphtha technology, which is other alternative processes, can save up to approximately 40% of SEC of traditional NCC process. This value equates to the 3.8 million tons of $CO_2$ mitigation and 147 billion won of CER per year.

• Carbon letters
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• v.24
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• pp.28-35
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• 2017

We demonstrated an effective way of preparing melt spinnable mesophase pitches via catalytic hydrogenation of petroleum residue (fluidized catalytic cracking-decant oil) and their subsequent thermal soaking. The mesophase pitches thus obtained were analyzed in terms of their viscosity, elemental composition, solubility, molecular weight, softening point and optical texture. We found that zeolite-induced catalytic hydrogenation under high hydrogen pressure contributed to a large variation in the properties of the pitches. As the hydrogen pressure increased, the C/H ratio decreased, and the solubility in n-hexane increased. The mesophase pitch with entirely anisotropic domains of flow texture exhibited good meltspinnability. The mesophase carbon fibers obtained from the catalytically hydrogenated petroleum residue showed moderate mechanical properties.

• Applied Chemistry for Engineering
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• v.29 no.2
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• pp.248-251
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• 2018

Catalytic pyrolysis of the waste paper cup containing coffee residual (WPCCCR) was performed using a fixed bed reactor and pyrolyzer-gas chromatography/mass spectrometry (Py-GC/MS). Non-catalytic pyrolysis of WPCCCR produced a large amount of oil together with gas and char. The use of both HZSM-5 and HY decreased the yields of oil and increased the yield of gas due to the additional catalytic cracking. Owing to the acidic catalytic properties of HZSM-5 and HY, catalytic Py-GC/MS analysis of WPCCCR increased the selectivity to aromatic hydrocarbons in product oil. Owing to properties of HZSM-5 having a stronger acidity and medium pore size, the catalytic pyrolysis of WPCCR over HZSM-5 produced much larger amounts of aromatic hydrocarbons than that of using HY.

• New & Renewable Energy
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• v.2 no.4 s.8
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• pp.70-77
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• 2006

The butane decomposition over the catalyst is an attractive method for the hydrogen production. The objective of the work was investigated the catalysis of carbon black in butane decomposition reaction. The Butane decomposition was performed over carbon black catalyst in a range of $500-1100^{\circ}C$. The butane conversion of thermal decomposition and catalytic decomposition were increased with increasing the reaction temperature The butane conversion of the thermal decomposition was higher than the butane conversion of the catalytic decomposition. Hydrogen and methane were mostly observed in the butane decomposition over $1000^{\circ}C$. Especially, the hydrogen yield was steadily increased with raising the reaction temperature, It could be known that the hydrogen yield of the catalytic decomposition was higher than one of the thermal cracking because the hydrogen productivity was improved by the catalyst. The deactivation of the catalyst was not observed in the reactivity test. The surface and crystalline of the fresh and used catalysts were characterized by TEM, BET surface area and XRD analysis, respectively. The fresh carbon black particles had mostly smoothly round-shaped surfaces. In the surface of the carbon black after the reaction, the deposited carbon was formed as the protrusion-shaped carbon and the cone-shaped. The proper peaks of carbon black appeared in XRD analysis.

• Applied Chemistry for Engineering
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• v.22 no.6
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• pp.627-630
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• 2011

We focus on a catalytic process based on direct injection method that can produce high-quality oils of gasoline and kerosene with various carbon-number feed oils. The reaction characteristics of a commercial catalyst were analyzed using a spouted bed reactor. Decane and pentadecane were used to compare the characteristics of the fixed bed and the spouted bed reactor. The yield of gasoline plus kerosene was highest at the reaction temperature of $550^{\circ}C$. For the spouted bed reactor, the at-a-pulse injection was more effective for catalytic cracking of feed oils than multiple consecutive injections. The reaction activity became higher as the carbon number of feed oil is larger.

• Clean Technology
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• v.17 no.1
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• pp.56-61
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• 2011

In this study, hydrocarcking of vacuum residue was carried out in an autoclave reactor at $450^{\circ}C$ and $500^{\circ}C$ with a commercial catalyst (HDM) and the quantitative product distributions were analyzed by GC-SIMDIS method or simple distillation. During catalytic hydrocracking, thermal cracking also occurred together with catalytic cracking and the higher conversion and selectivity of gasoline and naphtha were obtained at high reaction temperature. GC-SIMDIS and simple distillation revealed different results for the analysis of products produced at different hydrocracking temperatures; almost same results were obtained for the product produced at $500^{\circ}C$ but different ones for the product produced at $450^{\circ}C$. In the analysis of product produced at $450^{\circ}C$, the GC-SIMDIS showed that a main product was VGO while a main product in the simple distillation was diesel, which implies that the simple distillation for the $450^{\circ}C$ reaction was not accurate due to thermal cracking of the product by the simple distillation.

• Journal of the Korean Chemical Society
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• v.20 no.6
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• pp.469-478
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• 1976

Clinoptilolite zeolite samples were treated with hydrochloric acid, sulfuric acid and phosphoric acid of different strength and the adsorption characteristics and crystal structures of the original and acid-treated clinoptilolites were studied. By treating with hydrochloric acid, the adsorbed amount increased to 5-fold for nitrogen, to 3-fold for benzene, but for methanol no significant change was observed. As acid strength increased further, there were declines both in adsorption capacity and crystallinity. The results showed that the increase of adsorbed amount was caused by the rearrangement of the pore entrance and cation exchange. A method for determination of clinoptilolite content in natural mineral based on benzene adsorption on acid-treated sample is proposed. By this method, the original sample used in this study was found to contain approximately 40% of clinoptilolite. Using pulse technique in micro-catalytic reactor system, the catalytic activities of hydrochloric acid-treated clinoptilolites in cumene cracking and toluene disproportionation reactions were measured. For cumene cracking reaction, the maximum conversion was observed for the 0.5 N hydrochloric acid-treated sample. It is instructive to note that the maximum benzene adsorption was also observed for the sample treated with 0.5 N HCl. This suggest that the conversion rate was determined mainly by the rate of transport of reactants and the products through the pore structure. In the toluene disproportionation reaction, the same trend was observed. But the rate of deactivation was high for samples with strong acid sites. Since catalyst having higher activity was deactivated more easily, the conversion maximum was shifted to the sample treated with higher concentration of acid, -1N. The catalytic activity of $Ca^{2+} and La^{3+} ion exchanged samples for the toluene disproportion was much lower than that of acid-treated samples. Introduction of Ca^{2+} and La^{3+}$ into the pore structure apparently decreases the effective pore diameter of acid-treated clinoptilolite thus limiting the diffusion of reactants and products.

• Clean Technology
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• v.20 no.4
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• pp.359-366
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• 2014

Attrition characteristics of PKM1-SU particles, $CO_2$ absorbents for pre-combustion $CO_2$ capture process, and FCC particles, catalytic particles for hydro cracking of crude oil, were investigated at high temperature and high pressure conditions. Particle attrition tests were executed at various kinds of temperature ($0-400^{\circ}C$) and pressure (0-20 bar) conditions in a cylinder type bubbling fluidized bed with 15.1 cm diameter, 120 cm height and 1 mm orifice-sparger tube. Attrited particles before and after tests were analyzed by BET, optical microscopy, and particle size analyzer. Effects of bed material height (solid inventory) and steam injection were also verified by using ASTM D5757-95, conventional attrition test method.

• 한국연소학회:학술대회논문집
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• 2014.11a
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• pp.33-36
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• 2014

Gasification of biomass produces syngas containing CO, $H_2$ and/or $CH_4$, which can then be converted into energy or value-added fuels. One of key issues for efficient gasification is to minimize tar concentration in the syngas for use in a final conversion device such as gas engine. This study investigated the decomposition of primary tar by catalytic cracking using char as catalyst, of which the feature can be integrated into a fixed bed gasifier design. The pyrolysis vapor containing tar from pyrolysis of wood at $500^{\circ}C$ was passed through a reactor filled with or without char at $800^{\circ}C$ for a residence time of 1, 3 or 5 sec. Then, the condensable vapor (water and tar) and gases were analyzed for the yields and elemental composition. Four types of char particles with different microscopic surface area and pore size distribution: wood, paddy straw, palm kernel shell and activated carbon. The results were analyzed for the mass and carbon yields of tar and the composition of product gases to conclude the effects of char types and residence time.

• Journal of the Korean Chemical Society
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• v.21 no.2
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• pp.89-93
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• 1977

Faujasite type zeolite synthesized from kaolin minerals was cation-exchanged and the catalytic activities of $1-Butene{\rightarrow}2-butene$ took place readily even on zeolites having no strong acid sites. The order of activity for isobutene formation was La > H > Zn > Na-faujasite, La-faujasite showing much higher activity. The same trend was observed for propylene formation except that both La-and H-faujasite showed comparable activity. The results seem to indicate that the activities for 1-buten cracking and isomerization on zeolite are directly related to the strength and concentration of the acid sites on zeolites.