Docosane Research Articles

Mathematical modeling of multicomponent catalytic processes of petroleum refining and petrochemistry

Abstract This review summarizes Russian developments on the most important industrial processes of hydrocarbon feedstock refining according to the data of the last 15–20 years on the kinetics of deactivation of heterogeneous and liquid-phase catalysts under non-stationary conditions. The methodological aspects of the creation and application of kinetic models for the deactivation of heterogeneous and liquid-phase catalysts under non-stationary conditions are considered. It is shown that high efficiency of catalytic technologies is ensured by regulation of hydrodynamic and thermal conditions of industrial processes of gasoline reforming, alkane dehydrogenation, alkylation of benzene with higher alkenes and catalytic dewaxing using kinetic models, which take into account catalyst deactivation.

Tuning the product selectivity of SAPO-18 catalysts in MTO reaction via cavity modification

The AEI cavity of SAPO-18 catalyst was modified with zinc cations with the conventional ion exchange procedure. The cavity modification effectively tunes the product selectivity, and shifts the products from mainly propylene to comparable production of ethylene and propylene in methanol to olefin (MTO) reaction. The incorporation of zinc ions and the generation of bicyclic aromatic species in the AEI cavity of SAPO-18 catalysts introduce additional diffusion hindrance that exert greater influence on the relatively bulky products (e.g. propylene and higher olefins), which increase the selectivity to small-sized products (e.g. ethylene). It appears that the incorporated zinc cations facilitate the generation of lower methylbenzenes which promote the generation of ethylene. The cavity modification via incorporating zinc ions effectively tunes the product selectivity over SAPO molecular sieves with relatively larger cavity, which provides a novel strategy to develop the potential alternative to SAPO-34 catalysts for industrial MTO reaction.

Effect of preparation parameters on properties and performance of Pd/Al2O3 catalyst in saturation of olefins

The complete saturation of commercial olefin-containing (3.3 mol%) C4 stream over Pd/γ-Al2O3 catalysts was studied. The catalysts were prepared by wet impregnation of the support using acidified PdCl2 solutions. The effect of different preparation parameters such as HCl/PdCl2 ratio in impregnation solution, impregnation time and solution volume on palladium distribution and catalytic performance was investigated. The catalysts were characterized by N2 adsorption/desorption, ICP measurements, X-ray diffraction, temperature programmed desorption of ammonia (NH3-TPD) and scanning electron microscopy. Catalytic performance tests were carried out in a three-phase co-current trickle-bed reactor at 50 °C, 27 bar and high olefin conversions in accordance with industrial operating conditions. The catalysts showed different palladium distributions according to preparation procedure. The best performance was observed for egg-shell catalysts prepared by employing short impregnation times (5–10 min) and low competitor levels (HCl/PdCl2 = 2.2 mol mol−1) in impregnation solution. The catalyst lifetime was found to correlate with its activity which was explained by a parallel deactivation mechanism.

On the Limited Role of Electronic Support Effects in Selective Alkyne Hydrogenation: A Kinetic Study of Au/MOx Catalysts Prepared from Oleylamine‐Capped Colloidal Nanoparticles

AbstractWe report a quantitative kinetic evaluation and study of support effects for partial alkyne hydrogenation using oleylamine‐capped Au colloids as catalyst precursors. The amine capping agents can be removed under reducing conditions, generating supported Au nanoparticles of ∼2.5 nm in diameter. The catalysts showed high alkene selectivity (>90 %) at all conversions during alkyne partial hydrogenation. Catalytic activity, observed rate constants, and apparent activation energies (25–40 kJ/mol) were similar for all Au catalysts, indicating support effects are relatively small. Alkyne adsorption, probed with FTIR and DFT, showed adsorption on the support was associated with hydrogen‐bonding interactions. DFT calculations indicate strong alkyne adsorption on Au sites, with the strongest adsorption sites at the metal‐support interface (MSI). The catalysts had similar hydrogen reaction orders (0.7–0.9), and 1‐octyne reaction orders (∼−0.2), suggesting a common mechanism. The reaction kinetics are most consistent with a mechanism involving the non‐competitive activated adsorption of H2 on an alkyne‐covered Au surface.

Optimizing both the CoMo/Al2O3 catalyst and the technology for selectivity enhancement in the hydrodesulfurization of FCC gasoline

Herein, a series of alumina supports were prepared by rehydration-dehydration of the traditional γ-Al2O3 under different hydrothermal temperatures. After loading CoMo species, it was found the selectivity factor of corresponding CoMo/Al2O3 catalysts was improved greatly from 1.21 to 2.51 with the increased hydrothermal temperature of alumina supports in the hydrodesulfurization (HDS) of a model fluid catalytic cracking (FCC) naphtha. The improved HDS selectivity is attributed to the weakened metal-support interaction and lowered dispersion of MoS2 particles, resulting in catalysts with larger edge-to-corner ratios of CoMoS slabs ((fe/fc)CoMo). Besides, the recombination mercaptans formed by reaction of produced H2S and olefins were found as a big challenge to reach a high HDS conversion (S < 10 ppm) when only using the selective HDS catalyst (one-unit process). Therefore, a two-unit process has been developed by using a selective HDS catalyst to remove the most of the refractory sulfur compounds firstly, after which using another mercaptan-removing catalyst to deal with the recombination mercaptans specially. The catalytic results show that the two-unit process has a smaller olefin loss (4.38 v%) than that of one-unit process (7.08 v%) when reducing the sulfur concentration of a heavy FCC fraction to less than 10 ppm, thus resulting in a 0.7 unit less of the research octane number loss. The present work shows that high HDS conversion and low olefin hydrogenation conversion in selective HDS of FCC gasoline can be achieved through optimization design of both the selective HDS catalyst and the whole technology.

Challenge of Using Practical DFT to Model Fe Pendant Donor Diimine Catalyzed Ethylene Oligomerization

Molecular, Fe-catalyzed ethylene oligomerization provides access to a range of linear α-olefins (LAOs) that are used to produce polyethylene, lubricants, surfactants, and other commercial products. This work provides an experimental example of an Fe pendant donor diimine ((PDD)Fe) catalyzed ethylene oligomerization that showcases very high olefin oligomer purity without branching and provides K (propagation/(propagation + termination)) values of LAOs fractions, which show larger K values as a function of carbon chain length. This experimental example provided an anchor point to try to identify a practical density functional theory (DFT) protocol to model ethylene oligomerization branching, propagation/termination, and K values. Using M06-L DFT calculations, we successfully modeled the very high oligomerization purity for the (PDD)Fe catalyst, compared to the lower purity for the Fe tridentate pyridine bisimine (PBI)Fe catalyst, which showed enhanced regioselectivity for migratory insertion between Fe–H in...

Highly selective conversion of CO2 to light olefins via Fischer-Tropsch synthesis over stable layered K–Fe–Ti catalysts

K–Fe–Ti layered metal oxides (LMO) were prepared using solid-state reaction followed by in situ reduction and applied in CO2 hydrogenation to light olefins via Fischer-Tropsch synthesis process. The results showed that the molar ratio of K/Fe/Ti had dramatic effects on the textural and structural properties of the LMO and the catalytic performance. Layered structure K–Fe–Ti exhibited high olefin selectivity and stability for CO2 hydrogenation. The light olefin selectivity reached approximately 60% with an olefin/paraffin value of 7.3 over 0.8K–2.4Fe–1.3Ti, and the exfoliated LMO through acid treatment was found to weaken the interaction between Fe and Ti. This enabled the reduction and activation of iron oxides easier to form iron carbide species and promoted a shift from the reverse water gas shift reaction regime to hydrocarbon synthesis regime, contributing to higher hydrocarbons while lower CO.

English

Industrialization has come with environmental challenges. Industries like paper, printing, textile, leather and so on widely use chemical dyes whose waste treatment or degradability is difficult. Among various methods employed, the use of microbial enzymes is the most effective. The study aimed at producing laccase from identified yeast strains for potential industrial use in dye decolourization. Laccase produced by Kluyveromyces dobzhanskii DW1 and Pichia manshurica DW2 were purified and immobilized up to 65.2 and 73.1%, respectively. The crude, purified and immobilized forms of the enzymes were used to decolourize malachite green and methyl red dyes each at concentrations of 0.05 and 0.1 g/L. The highest percentage decolourization by K. dobzhanskii DW1 was 81.50% (immobilized) and 87.50% (purified), respectively for malachite green and methyl red dyes while P. manshurica DW2b (crude) had 84.40 and 76.89%, respectively. The Fourier transform infrared (FTIR) spectrum of the dyes was collected within a scanning range of 4000 to 400 cm-1. The spectrum of methyl red dye by the purified K. dobzhanskii DW1 laccase showed disappearance of some chemical groups (peak), while the crude P. manshurica DW2 laccase removed the main azo-group, alcohol/phenol and higher alkane (1487.17) groups. The spectrum of untreated malachite green also showed 25 peaks with one disulphide, 2 aliphatic halogens, 2 thio ethers, 3 sulphones, 4 imino groups among other chemical groups. The decolourization of the dye with the immobilized K. dobzhanskii DW1 laccase showed a spectrum of 17 peaks with the removal of the disulphide (420.5), one aliphatic halogen (C-I), thio ether, 2 sulphone, 4 imino and 2 higher alkanes, while the crude P. manshurica DW2 laccase removed the 2 aliphatic halogen, 4 imino, 1 amine, 2 alkane and 2 of the 3 alcohol/phenol chemical groups. The removal of the main components (azo chemical group) of the dyes proved their effectiveness in decolourisation and bioremediation of the textile wastes. &nbsp; Key words: Decolourisation, azo-dye, laccase, immobilized, FT-IR spectra.

Linear α-olefin production with Na-promoted Fe-Zn catalysts via Fischer-Tropsch synthesis.

The production of linear alpha-olefins (α-olefins) is a practical way to increase the economic potential of the Fischer–Tropsch synthesis (FTS) because of their importance as chemical intermediates. Our study aimed to optimize Na-promoted Fe1Zn1.2Ox catalysts such that they selectively converted syngas to linear α-olefins via FTS at 340 °C and 2.0 MPa. The Fe1Zn1.2Ox catalysts were calcined at different temperatures from 350 to 700 °C before Na anchoring. The increase in the size of the ZnFe2O4 crystals comprising the catalyst had a negative effect on the reducibility of Fe oxides and the particle size of Fe5C2 during the reaction. The Na species in the catalyst restrained the reduction of Fe1Zn1.2Ox but facilitated the formation of Fe5C2. When pure Fe1Zn1.2Ox was calcined at 400 °C, the corresponding catalyst (i.e., Na0.2/Fe1Zn1.2Ox (400)) exhibited higher catalytic activity and stability than the other catalysts for a 50 h reaction. Compared to the other catalysts, Na0.2/Fe1Zn1.2Ox (400) enabled a higher number of active Fe carbides (Fe5C2) to intimately interact with the Na species, even though the catalyst had a lower total surface basicity based on surface area. The Na0.2/Fe1Zn1.2Ox (400) showed a maximum hydrocarbon yield of 49.7% with a maximum olefin selectivity of 61.3% in the C1–C32 range. Examination of the reaction product mixture revealed that the Na0.2/Fe1Zn1.2Ox catalysts converted α-olefins to branched paraffins (13.9–19.5%) via a series of isomerization, skeletal isomerization, and hydrogenation reactions. The Na0.2/Fe1Zn1.2Ox (400) catalyst had a relatively low consumption rate of internal olefins compared to other catalysts, resulting in the lowest selectivity for branched paraffins. The Na0.2/Fe1Zn1.2Ox (400) showed a maximum α-olefin yield (26.6%) in the range C2–C32, which was 27.9–50.0% higher than that of other catalysts. The α-olefin selectivity in the C5–C12 range for the Na0.2/Fe1Zn1.2Ox (400) was 37.5% relative to the total α-olefins.

The production of renewable aviation fuel from waste cooking oil. Part I: Bio-alkane conversion through hydro-processing of oil

Renewable aviation fuel produced from hydro-processing has been a commercially available technique currently. Studies conducted recently were toward finding an appropriate catalysts to produce the jet fuel range products with high normal alkanes and low aromatics. This study focused on hydro-processing of waste cooking oil (WCO) into straight alkanes, which can serve as the blendstock for aviation fuel after further cracking and isomerizing, over two different catalysts, pre-sulfurized NiMo/γ-Al2O3 and Pd/C, under various experimental conditions such as reaction temperature, pressure, liquid hourly space velocity (LHSV) and H2-to-oil ratio. The resulting liquid and gas products from the two catalysts were analyzed through GC-MS/FID and GC-TCD for judging the performances of hydro-deoxygenation (HDO) as well as decarboxylation (DCO2)/decarbonylation (DCO). The fresh and spent catalysts were examined through XRD, FTIR, TGA and SEM to characterize the catalysts before and after hydro-processing. The performance of Pd/C, based on the concentrations of produced C15∼C18 normal alkanes, was higher than NiMo/γ-Al2O3 with low reaction temperature, low hydrogen pressure, low LHSV, low H2-to-oil ratio and short time-on-stream.

Preliminary assessment of outdoor and indoor air quality in Yangon city, Myanmar

Air pollution related problems in urban areas of developing countries get bigger quickly. Yangon is the most urbanized and most densely populated city in Myanmar. Information on air quality of Yangon is still lacking. Therefore, we conducted this study for initial assessment of outdoor and indoor air quality of Yangon. Four kinds of diffusive air samplers were used to measure volatile organic compounds (VOCs), ozone and carbonyl compounds, acidic gases and ammonia. As a result of this study, higher alkanes were found dominant among outdoor VOCs. Benzene/toluene ratios ranged from 0.15 to 0.53. Formaldehyde/acetaldehyde ratios varied from 1.5 to 2.4. Maximum outdoor ozone value was 26 μgm−3. A strong negative correlation between outdoor ozone and nitrogen dioxide concentrations was noted. Compared with previous local studies, outdoor nitrogen dioxide and sulfur dioxide concentrations were found to be on the increasing trend. The indoor/outdoor ratios at some sites revealed that there were indoor sources for α-pinene, d-limonene, p-dichlorobenzene and methyl isobutyl ketone. The ratios of pollutants with outdoor sources mostly ranged between 1 and 2. In conclusions, although it is a preliminary assessment, the findings can provide invaluable information towards comprehensive picture of air quality of Yangon. Outdoor air quality is found contaminated with pollutants most of which are traffic-related indicating that the city is now facing high traffic volume greater than before. Indoor air quality is varied with indoor characteristics of the buildings. Gases with health concern are identified in indoor air. Inadequate ventilation may precipitate poor indoor air quality.

Synergic Effect of Copper and Palladium for Selective Hydrogenation of Alkynes

The design of palladium-based catalysts with improved selectivity, while maintaining high activity in hydrogenation reactions and avoiding the use of lead or ligands is still a major concern in heterogeneous catalysis. Here, a novel protocol has been proposed to prepare colloidal PdCuy nanoparticles with tailored metal composition, enabling a remarkable improvement in the semihydrogenation of alkynes when compared to pure Pd or a physical mixture of Cu and Pd catalysts. The PdCuy bimetallic catalyst with 1:4 Pd/Cu atom ratio showed the best performance. The synergistic effect between the closely contacting Pd and Cu species resulted in full conversion of alkyne and high alkene selectivity for a broad range of multifunctionalized substrates under very mild conditions (30 °C and 1 bar of H2).

Terpenes from Otostegia integrifolia

The essential oil and chloroform extract of air-dried leaves of Otostegia integrifolia Benth. were investigated for the first time using analytical and preparative gas chromatography (GC), GC-mass spectrometry (MS) and NMR techniques. A total of 40 constituents including monoterpenes, sesquiterpenes, diterpenes and their derivatives were identified. A prenylbisabolane type diterpene, 1-methyl-4-(5, 9-dimethyl-1-methylene-deca-4, 8- dienyl) cyclohexene was identified as a major component. The chloroform extract of the leaves yielded two new labdane type diterpenoids, 15, 16-epoxy-3a, 9a-dihydroxy-labda- 13(16), 14-diene and 9(13), 15(16)-diepoxy-3a-hydroxy-16-dihydrolabda-14-ene, a saturated hydrocarbon, pentatriacontane, and stigmasterol. The structures of the isolated compounds were established by spectroscopic methods. Keywords: Otostegia integrifolia Benth.; Lamiaceae; Essential oil, Furanolabdane diterpenes, Otostegindiol, Preotostegindiol, (+)-Axinyssene, Pentatriacontane, Stigmasterol

Hydrogenation of CO2 to light olefins on CuZnZr@(Zn-)SAPO-34 catalysts: Strategy for product distribution

Composite catalysts containing CuZnZr(CZZ) and SAPO-34 were prepared and applied to the hydrogenation of CO2 to light olefins via the tandem reactions of methanol synthesis and methanol to olefins. The product selectivity was significantly affected by the composite methods, mass ratio of CZZ and SAPO-34 and the acid density of SAPO-34. Compared with physically mixed CZZ/SAPO-34, assembled core–shell CZZ@SAPO-34 increased the selectivity of olefins and inhibited CH4 formation, due to reduced contact interface and hydrogenation ability on the metal sites. Furthermore, reducing the acidity of SAPO-34 by Zn addition greatly restrained secondary reactions of the primary olefins. A high olefin selectivity of 72% was achieved over CZZ@Zn-SAPO-34 (4/1) at H2/CO2 of 3, 6000 h−1, 400 °C and 2 MPa. Because the concentration of intermediate methanol remained low level during the reaction and small amount of CZZ was doped into Zn-SAPO-34, a large amount of C3 and C4 hydrocarbons were formed owing to the hydrogenation and hydrogen transfer reactions of primary C2–C4 olefins.

CoMo/Al2O3 catalysts prepared by tailoring the surface properties of alumina for highly selective hydrodesulfurization of FCC gasoline

Traditionally prepared CoMo/Al2O3 hydrotreating catalysts, although efficient for deep desulfurization, are not suitable for fluid catalytic cracking (FCC) gasoline hydrodesulfurization (HDS) due to their high olefin hydrogenation (HYD) activity especially when the HDS conversion is high. Herein, two alumina supports with tailored surface properties were prepared by calcination of hydrothermally treated pseudo-boehmite (PB) and hydrothermally treated γ-Al2O3 in order to design CoMo/Al2O3 catalysts with high HDS selectivity. It is found that compared with the traditional alumina prepared by direct calcination of PB, the two tailored alumina supports have notably decreased surface area, surface hydroxyl groups and Lewis acidity. The characterization results show that the catalysts obtained from CoMo supported on the two tailored supports have lowered Mo dispersion, weakened metal-support interaction, increased Mo sulfidation degree and longer MoS2 slabs than the traditional CoMo/Al2O3 catalyst. The catalytic results of three different CoMo/Al2O3 catalysts in the HDS of a full-range FCC gasoline show that the HDS selectivity is increased remarkably (selectivity factors increase from 5.5 to 11.0) with the decreased surface area, surface hydroxyl groups and Lewis acidity of the alumina supports. Especially, CoMo supported on the tailored alumina support prepared by calcination of hydrothermally treated γ-Al2O3 (denoted as CoMo/Al2O3-3) exhibits a 15% lower olefin HYD activity than traditional CoMo/Al2O3 catalyst even at the same and high HDS conversion (95%). The greatly improved HDS selectivity can be well explained by the increased slab length of supported MoS2 particles, resulting in notably decreased HYD activity catalyzed by the corner sites. Besides, CoMo/Al2O3-3 also shows superior HDS selectivity in the HDS of a real heavy FCC naphtha, where the sulfur content can be reduced from 309 ppm to 10 ppm with an accompanying RON loss of only 1.0 unit.

Pillar5arenes as Supramolecular Hosts in Aqueous Biphasic Rhodium‐Catalyzed Hydroformylation of Long Alkyl‐chain Alkenes

AbstractAqueous biphasic catalysis continues to attract strong interest, especially when very hydrophobic substrates are concerned. Indeed, their insolubility in water strongly limit their transformation by water‐soluble organometallic catalysts. To improve contacts between the substrate‐containing organic phase and the catalyst‐containing phase, one of the best solutions consists in using interfacial additives capable of supramolecularly recognize the substrate and/or the catalyst. In the present study, modified pillar5arenes are considered as interfacial additives and their performance is assessed in Rh‐catalyzed hydroformylation of long alkyl‐chain alkenes (higher olefins). Pillar5arenes substituted by carboxylate functions and methyl groups P5 A‐(Me)10‐x‐(CH2COOMe)x are compared to pillar5arenes substituted by polyethylene glycol (PEG) chains (P5 A‐(Me)5‐(PEG)5 and P5 A‐(PEG)10). Utilization of P5 A‐(Me)10‐x‐(CH2COOMe)x leads to high conversion and regioselectivity (linear/branched aldehyde ratio) in Rh‐catalyzed hydroformylation of 1‐decene and 1‐hexadecene. Compared with other interfacial additives such as modified cyclodextrins, the studied pillar5arenes show lower chemo‐selectivity, similar catalytic activity and higher regioselectivity.

Propane to light olefins by one-pot cascade and series reactions

Propane is selectively converted to propylene via propane dehydrogenation (PDH) process for an on-purpose propylene usage. Due to regional market demands, olefin interconversion for propylene-to-ethylene (PTE) is required to control the supply-demand of light olefins. Our concern centers on combining the PDH and PTE reactions to achieve a simple catalytic process for selective production of light olefins from propane. Herein, converting propane to light olefins is investigated via cascade and series PDH-PTE reactions over highly selective two catalysts. From the catalytic results, selectively produced propylene over a PDH catalyst (Cr2O3/Al2O3) from propane was readily converted to other light olefins over a PTE catalyst (modified ZSM-5). The modified ZSM-5 as the PTE catalysts was further studied in the both cascade and series reactions with different reaction conditions in order to find an optimum reaction condition for high olefin yield and selectivity with low methane selectivity as well as to investigate the influence of process parameters on the catalytic activity. The AHFS treated ZSM-5 (AHFS-ZSM-5) as the PTE catalyst in PDH-PTE series reaction exhibited a superior light olefin yield (50.7 wt%) and olefin selectivities up to 76.7 wt% (26.9 wt% ethylene, 38.0 wt% propylene, and 11.8 wt% butenes) with low methane selectivity (4.27 wt%) at 550 °C, WHSV 7 h−1, and propylene partial pressure in the PDH model feed 0.025 MPa.

Zeolite@Pd/Al2O3 Core–Shell Catalyst for Efficient Hydrodeoxygenation of Phenolic Biomolecules

The bifunctional catalysts containing metal nanoparticles and acidic centers have been widely used in the upgrading of biomass-derived molecules via a catalytic hydrodeoxygenation process, but the synergistic efficiency of metal–acid is generally unsatisfactory. Herein, we report a core–shell catalyst containing aluminosilicate zeolite crystals encapsulated by alumina supported Pd nanoparticles (zeolite@Pd/Al2O3) to be highly efficient for the hydrodeoxygenation of biomass-derived molecules. Compared with the reference catalysts involving a physical mixture of zeolite crystals and Pd/Al2O3 (zeolite + Pd/Al2O3), Pd nanoparticles supported on the zeolite crystals (Pd/zeolite), and Pd nanoparticles fixed within zeolite crystals (Pd@zeolite), the zeolite@Pd/Al2O3 exhibits simultaneously high activity, alkane selectivity, and good recyclability in the continuous recycle tests. The advantages of the zeolite@Pd/Al2O3 catalyst are reasonably attributed to its maximized metal–acid synergistic efficiency. Also, the...

Modifying Zeolite ZSM-5 to Increase the Yield of Light Olefins in Cracking Feedstocks of Petroleum and Vegetable Origin

The effect modifying the HZSM-5 zeolite contained in a bizeolite catalyst has on the conversion of hydrotreated vacuum gas oil, vegetable oil, and a vacuum gas oil–vegetable oil mixture under conditions of catalytic cracking is investigated. It is found that modification lowers both the specific surface area and the volume of the meso- and micropores of HZSM-5 zeolite; the higher the phosphorus content, the greater the reduction in the main characteristics of the pore structure of the zeolite. A drop in the total acidity of P/HZSM-5 and a quantitative redistribution of weak and medium-strength acid sites are also observed. Catalytic tests of the zeolites in the cracking process show that phosphorus modification helps increase the total yield of propane–propylene and butane–butylene fractions with high olefin contents. Alkaline treatment of HZSM-5 zeolite with a high SiO2/Al2O3 ratio facilitates the extraction of silicon and increases the specific surface area of mesopores considerably. In addition, weakening of the strong acid sites of the zeolite and/or a change in the accessibility of these sites due to the partial removal of silicon is observed.

BLENDS OF ALIPHATIC POLYAMIDES WITH FUNCTIONALIZED POLYOLEFINS: INTERPHASE INTERACTIONS, FEATURES OF THE RHEOLOGICAL BEHAVIOR OF MELTS, STRUCTURE AND MECHANICAL PROPERTIES

The effect of addition of functionalized polyolefins (fPO) in an amount of 28 wt. % – mixtures of polyethylene and copolymer of ethylene with higher olefin containing 0.43 and 0.77 wt. % grafted monomer having two carboxyl groups in its composition – to aliphatic polyamides PA6 and PA66 on the structural features, the rheological behavior of melts and the mechanical properties of mixed materials was investigated. The materials studied were prepared by reactive mixing of the components in a melt in an extrusion reactor. It is shown that mixtures of PA66/fPO are characterized by more significant changes in the characteristics under analysis compared with those based on PA6 when the concentration of a grafted monomer is varied. An abnormally sharp increase (by more than two decimal orders) of the melt viscosity of a mixture of PA66 with fPO containing 0.77 wt. % of the grafted monomer, compared with the viscosity of initial PA66, is due to the specificity of the interphase interactions in the mixtures.