Hydrodechlorination of polychlorinated molecules using transition metal phosphide catalysts

Catalytic Deoxygenation of Palm Oil Over Iron Phosphide Supported on Nanoporous Carbon Derived from Vinasse Waste for Green Diesel Production

The vinasse waste was effectively converted to nanoporous carbon (NPC) via hydrothermal carbonization with potassium hydroxide (KOH) activation. The nanoporous carbon (NPC) exhibited a maximum surface area of 1018 m2/g and it was utilized as a catalyst for the conversion of palm oil into green diesel fuel. The supported NPC catalyst was fabricated via a wet impregnation technique, where finely distributed iron phosphide (FeP) particles were cemented. The FeP/NPC catalyst was evaluated for its physicochemical characteristics using various techniques including X-ray diffraction (XRD), nitrogen sorption analyzer, transmission electron microscopy (TEM), and energy dispersive X-ray spectrometry (EDS) mapping. An investigation was conducted to examine the effects of different temperatures (ranging from 280 to 360 °C) on the conversion of palm oil through deoxygenation reactions. The FeP/NPC catalyst exhibited remarkable particle dispersion and surface area. At a reaction temperature of 340 °C, the FeP/NPC catalyst had the best selectivity for green diesel, reaching 68.5%. The finding implies that FeP catalysts, when supported, hold significant promise for converting triglycerides into renewable diesel fuel. Moreover, they provide the advantage of being more cost-effective than valuable metals, while demonstrating excellent catalytic efficiency in the production of biofuels. Furthermore, it has been shown that the FeP/NPC catalyst can be recycled by subjecting it to heat treatment to remove impurities and obtain reduction.

Applicability of Nickel-Based Catalytic Systems for Hydrodehalogenation of Recalcitrant Halogenated Aromatic Compounds

This review summarizes recent applications of nickel as a nonprecious metal catalyst in hydrodehalogenation (HDH) reactions of halogenated aromatic compounds (Ar–Xs). Nickel-based HDH catalysts were developed for reductive treatment of both waste containing concentrated Ar–Xs (mainly polychlorinated benzenes) and for wastewater contaminated with Ar–Xs. Ni-catalyzed HDH enables the production of corresponding nonhalogenated aromatic products (Ar–Hs), which are principally further applicable/recyclable and/or Ar–Hs, which are much more biodegradable and can be mineralized during aerobic wastewater treatment. Developed HDH methods enable the utilization of both gaseous hydrogen via the direct HDH process or other chemical reductants as a source of hydrogen utilized in the transfer of the hydrodehalogenation process. This review highlights recent and major developments in Ni-catalyzed hydrodehalogenation topic since 1990.

Palm Oil Conversion to Bio-Jet and Green Diesel Fuels over Cobalt Phosphide on Porous Carbons Derived from Palm Male Flowers

Porous carbon was successfully synthesized from palm male flowers (PMFs), using microwave-assisted potassium hydroxide (KOH) activation and was used as a catalyst support for the conversion of palm oil into bio-hydrocarbons, in fractions of green diesel and bio-jet fuel. Palm male flower-derived porous carbon (PC), consolidated with well dispersed cobalt phosphide (CoP) nanoparticles, was synthesized by simple wet-impregnation with subsequent thermal treatment. The physicochemical properties of the synthesized CoP/PC catalysts were evaluated by various techniques including proximate and ultimate elemental analysis, FTIR, XRD, N2 sorption, SEM, TEM–EDS, and NH3-temperature programmed desorption (TPD). The effects of the pyrolysis temperatures (600−900 °C), used for the impregnated samples before the reduction process, on catalyst properties and catalytic performance were investigated. Moreover, the effect of a liquid hourly space velocity of 0.5–1.5 h−1 and reaction temperatures of 340–420 °C was studied in the palm oil conversion. The catalyst pyrolyzed at 600 °C possessed the greatest particle dispersion and surface area, and showed the highest yield of liquid hydrocarbon product (C9–C18). We also found that the high pyrolysis temperature above 800 °C partially transformed the Co2P phase into CoP one which significantly exhibited higher cracking activity and bio-jet selectivity, due to the improved acidity of the catalyst.

Microwave assisted combustion of phytic acid for the preparation of Ni2P@C as a robust catalyst for hydrodechlorination

Ni₂P@C facilely prepared by microwave assisted combustion with phytic acid and nickel nitrate exhibits even higher activity for the hydrodechlorination of HCFC-22 than Pd/C.

Catalysis of the hydrodechlorination of 4-chlorophenol and the reduction of 4-nitrophenol by Pd/Fe3O4@C

A recyclable and efficient magnetic core–shell Pd/Fe₃O₄@C nanocatalyst is applied in the HDC of 4-CP and hydrogenation of 4-NP.

A simple method to freely adjust the crystalline phase and micro-morphology of NixPy compounds

Different crystalline phase of Ni_xP_y compounds with different morphology were successfully fabricated via a hydrothermal method assisted by urea.