• 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.

• Applied Chemistry for Engineering
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• v.8 no.2
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• pp.191-196
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• 1997

The isothermal reduction on $Pt/MoO_3/SiO_2$ at $50^{\circ}C$ demonstrates that the rate of hydrogen spillover is increased as calciantion temperature increases. That is due to the overlayer formation over the surface of Pt crystallites, investigated by TEM and CO chemisorption. It is known that reaction mechanism of skeletal isomerization of 1-butene into iso-butene is composed of 2 step such as formation of carbonium ion and isomerization of methyl group. It is expected that the increase of i-butene yield after calcination at $250^{\circ}C$ is due to increased rate of hydrogen spillover coming from first, overlayer formation over Pt surface and second, chlorine lessoning from $PtCl_x$ precursor.

• Macromolecular Research
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• v.17 no.5
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• pp.296-300
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• 2009

Ethylene-1-butene copolymers were prepared with $SiO_2$-supported $TiCl_4$ catalyst by changing of 1-butene/ethylene molar ratio in feed, and the resulting copolymers were analyzed using temperature rising elution fractionation (TREF) and crystallization fractionation (Crystaf) methods to investigated the influence of $C_4/C_2$ molar ratio in feed on chemical compositional distribution and other parameters such as molecular weight and its distribution. TREF analysis showed that the copolymers had a broad and bimodal chemical compositional distribution (CCD) regardless of the content of 1-butene in the copolymer. The chemical composition was in the range of 5 to 55 branches per 1,000 carbons for all copolymers prepared in the study. Furthermore, the broader CCD was revealed for the copolymers having the higher content of 1-butene. Crystaf analysis did not showed a bimodal CCD for the copolymers having the 1-butene content of less than 5.1 wt%. The lower crytalline part having 1-butene content in Crystaf analysis was less than of TREF analysis.

• Korean Chemical Engineering Research
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• v.45 no.4
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• pp.351-355
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• 2007

It is necessary to convert butene-2 into butene-1 with higher added-values through positional isomerization. In this study, hydro-isomerization of butene-2 with hydrogen over Pd/alumina catalysts was investigated in a fixed bed reactor. The yield of butene-1 over Ld-265 catalyst was higher than that over other catalysts. The yield of butene-1 was highest (5.3%) under the conditions of reaction temperature of $75^{\circ}C$, reaction pressure of 150 psig, 2-butene flow rate of 48 cc/h and hydrogen flow rate of 3 cc/min. We conducted simulation for the process composed of a hydro-isomerization reactor and a distillation tower. In the case of 78% of tray efficiency, we obtained over 99% pure butene-1 through a distillation tower with 171 steps (R=120).

• Journal of the Korean Chemical Society
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• v.21 no.6
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• pp.422-426
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• 1977

Transition-metal-loaded zeolite Y catalysts were prepared from LaY by exchanging with cobalt, nickel and palladium ions, followed by reduction in a hydrogen stream. The reactions of 1-butene and n-butane were studied on Co-, Ni-and Pd-loaded Y as well as La-exchanged Y using micro-catalytic pulse technique. For 1-butene reaction Ni-, Co-, Pd-loaded Y and La-exchanged Y all showed high activity suggesting that the acidic component, not the metallic component, was primarily responsible for the activity. For n-butane reaction on La-exchanged Y, the addition of 1-butene enhanced the activity. Significant cracking conversion of n-butane was observed for Ni-and Pd-loaded Y. Activity was higher on samples reduced at higher temperature and of higher metal content. It seems that the dehydrogenation to butenes at metallic sites is the primary step in the n-butane cracking reaction. On Ni-Y the cracking product was C_1$ both from the mixture of 1-butane and hydrogen and from n-butane. It may be that on Ni-Y, n-butane is dehydrogenated to butenes and subsequently hydro-cracked to C_1$.

• Journal of the Korean Chemical Society
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• v.13 no.4
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• pp.333-339
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• 1969

Synthesis and chemical properties of 1,4-bisdiazo-2-butene have been studied. 1,4-Bisdiazo-2-butene which was very unstable produced in protic solvents 1,3-butadiene and one unidentified substance instead of ring compounds. The reaction in aprotic solvents remains for further investigations.

• Bulletin of the Korean Chemical Society
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• v.35 no.9
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• pp.2669-2672
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• 2014

Double bond migration of butene-2 to butene-1 over ${\eta}$-alumina was investigated. The effects of calcination temperature on catalytic properties were analyzed by applying BET surface area, XRD, $NH_3$-TPD, and FT-IR of adsorbed pyridine techniques. The highest activity of the ${\eta}$-alumina catalyst calcined at $600^{\circ}C$ could be attributed not only to the highest amount of weak and medium strength acid sites, but also to the highest ratio of medium to weak strength Lewis acid sites.

• Proceedings of the KAIS Fall Conference
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• 2004.11a
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• pp.280-283
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• 2004

Effect of H2 spillover rate as function of reduction temperature on reaction kinetics was evaluated. Reaction kinetics including yield, conversion, activation energy and selectivity of 1-butene isomerization over Pt/HxMoO/SiO were measured as reaction temperature was increased. While conversion of 1-butane was decreased, yield of iso-butene was increased. Two kinds of reaction mechanism were proposed from the change of selectivity as function of temperature.

• Journal of the Korean Chemical Society
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• v.49 no.1
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• pp.7-15
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• 2005

• Journal of the Korea Academia-Industrial cooperation Society
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• v.5 no.1
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• pp.34-37
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• 2004

Effect of $H_2$ spillover rate as functon of calcination temperature on reaction kinetics was evaluated. Reaction kinetics including yield, conversion and selectivity of 1-butene isomerization over $Pt/HxMoO_3/SiO_2$ were measured as reaction temperature was increased. While conversion of 1-butane was decreased, yield of iso-butene was increased. Two kinds of reaction mechanism were proposed from the change of selectivity as function of temperature.