Mexican Institute of Petroleum

About: Mexican Institute of Petroleum is a government organization based out in Mexico City, Mexico. It is known for research contribution in the topics: Catalysis & Asphaltene. The organization has 3273 authors who have published 4170 publications receiving 87269 citations.

Spectroscopic study and catalytic evaluation of mesostructured Al-MCM-41 and Pt/H3PW12O40/Al-MCM-41 catalysts

Abstract: Mesostructured Al-MCM-41 materials (referred as CSA n , where n = Si/Al molar ratio = 50, 30 and 10, respectively) and 12-tungstophosphoric acid promoted Pt/Al-MCM-41 catalysts were investigated by a variety of spectroscopic techniques Aluminum ions were distributed within the resultant solid having 4, 5 or 6-coordination, in different proportion, which correlate with the formation of Bronsted acidity Grafting the H 3 PW 12 O 40 heteropolyacid (referred as HPW) on the Al-MCM-41 solids not only noticeably enhanced, by 2–3 times, the number of Bronsted acid sites, but also greatly improved the acidity strength, with respect to that of the bare host The primary structure of the Keggin units of the supported heteropolyacid was largely preserved after calcination at 350 °C; however, small parts of the Keggin units were strongly distorted or deformed due to the strong interaction between the heteropolyanions and the hydroxyl groups of the support Catalytic evaluation confirmed that 1 wt%Pt/25 wt%HPW/Al-MCM-41 (denoted as Pt/HPW/CSA n ) catalysts were very active for n-heptane isomerization in the presence of hydrogen under an atmospheric pressure condition High yield of multibranched isoheptanes was produced, which was dependent on the pore diameter and the Bronsted acidity of the catalysts The molar ratio of multibranched to monobranched isoheptanes is much higher than that reported in the literature under similar reaction conditions using zeolite-containing catalysts, showing the potential of producing high octane number fuel through the approach of n-heptane hydroisomerization by using our novel mesostructured catalysts

Statistical mechanics approach to lock-key supramolecular chemistry interactions.

Abstract: In the supramolecular chemistry field, intuitive concepts such as molecular complementarity and molecular recognition are used to explain the mechanism of lock-key associations. However, these concepts lack a precise definition, and consequently this mechanism is not well defined and understood. Here we address the physical basis of this mechanism, based on formal statistical mechanics, through Monte Carlo simulation and compare our results with recent experimental data for charged or uncharged lock-key colloids. We find that, given the size range of the molecules involved in these associations, the entropy contribution, driven by the solvent, rules the interaction, over that of the enthalpy. A universal behavior for the uncharged lock-key association is found. Based on our results, we propose a supramolecular chemistry definition.

Parameterized transient model of a pipeline for multiple leaks location

Abstract: This work deals with the location of multiple leaks in a pipeline when only the flows and pressures of the fluid at the extremes of the line are known. The key of the leaks' detector which should operate in quasi-real-time is the family ℱ of parameterized transient models for all two leaks scenarios in the pipeline. The family ℱ of dynamic models is obtained by considering the equivalence in the steady-state of a leak at position zeq with two leaks. This equivalence reduces the dimension of the unknown parameters' vector in the dynamic model from four to two. To estimate the specific parameters of ℱ , an off-line identification process is suggested which minimizes the quadratic error between the pipeline data and the member of the family. Results of the leak detector with 12 scenarios offered estimation errors less than 1% in all the cases for a water pipeline of 200 [m]. This illustrates the potentiality of the parameterized transient model for the identification of multiple leaks.