Impact of As-Prepared and Purifıed Multi-Walled Carbon Nanotubeson the Liquid-Phase Aerobic Oxidatıon of Hydrocarbons

Abstract

The article presents simple kinetic approaches to study the effect of multi-walled carbon nanotubes (MWCNTs) additives on the aerobic oxidation of hydrocarbons and to propose real acceptable mechanisms of the process. The aerobic liquid phase low-temperature oxidation of ethylbenzene conducted in the presence of multi-walled carbon nanotubes has been used as a model pattern. Kinetic analysis established the catalytic action associated with the presence of the iron compounds in inner channels of MWCNTs. These compounds are identified as ferric carbides provoking decomposition of the ethylbenzene hydroperoxide and thereby suppressing the competitive route of alky-peroxide radicals addition to the nanocarbon cage. Thus the reaction finally proceeds in the autocatalytic mode.Contradictory conclusions on the effect of CNTs on the oxidation chain processes existing in the literature are associated with the lack of control over nature and content of metal impurities in channels of nanotubes.

Aerobic-peroxide oxidation of naphthalene in the presence of transition metal on a nanocarbon carrier

“…При этом было использовано сразу два оксиданта -молекулярный кислород (воздух) и пероксид водорода. Ранее мы уже показали кинетическими методами, что металлсодержащие углеродные нанотрубки проявляют значительную каталитическую активность при аэробном окислении алкилароматических углеводородов [12,30].…”

“…Массовая доля железосодержащих Рис. 5. лабораторная CVD установка для синтеза углеродных нанотрубок примесей в МУНТ составляет как правило несколько весовых процентов [36].…”

Hydrogels Based on Natural Polymers for Cardiac Applications

“…Different types of acids and their mixtures such as HNO 3 , HCl, and a mixture of HNO 3 and H 2 SO 4 were used in the oxidation of CNTs. [20][21][22][23][24][25][26] Treatment with acid or a mixture of acids helps in the removal of metals and other impurities present in the CNTs which might have been introduced during the synthesis process. It further helps to overcome the hydrophobicity problem of CNTs and provides the condition for faster electron transfer causing increased conductivity.…”