Comparison of potassium catalysts on zeolite sodium A and X in transesterification of palm oil and active species specification.

Heterogeneous catalysts consisting of potassium supported on zeolites are active for transesterification, but the effect of zeolite properties is not clearly understood. This work compares catalysts containing 12 wt.% potassium on zeolite sodium A and X (12K/NaA and 12K/NaX) in terms of performance and physicochemical properties.

Extraction of silica from sugarcane bagasse ash and its utilization in zeolite 4A synthesis for CO adsorption.

Sugarcane bagasse ash (SCBA) is a solid waste containing a high amount of silica (SiO) and is suitable to utilize as a silica source for synthesizing zeolite NaA. SCBA is typically calcined at high temperatures before silica extraction. The method is not environmentally friendly because it consumes energy and produces CO.

The Synthesis of Well-Dispersed and Uniform-Sized Zeolite NaY by Adding Non-Refluxed and Acid-Refluxed Cogon Grass.

Zeolite NaY synthesized from a typical procedure could suffer from agglomeration. Adding non-refluxed cogon grass (NG) to the synthesis gel could produce NaY with good dispersion and uniform crystal size. Small molecules produced from cogon grass in alkaline conditions could prevent agglomeration.

Synthesis and Characterization of Zeolite NaY Dispersed on Bamboo Wood.

Zeolites in powder form have the potential to agglomerate, lowering access to active sites. Furthermore, a suspension of fine zeolite powder in liquid media is difficult to separate. Such drawbacks could be improved by dispersing zeolite crystals on support materials.

Structural elucidation of hexavalent Cr adsorbed on surfaces and bulks of FeO and α-FeOOH.

Magnetite (FeO) and goethite (α-FeOOH) were synthesized a hydrothermal approach and utilized as adsorbents for Cr removal in an aqueous medium. The typical crystal structures of the synthesized FeO and α-FeOOH were confirmed by XRD and TEM. FeO in a spherical shape with a surface area of 32 m g was established.

Paraquat adsorption on NaX and Al-MCM-41.

The aim of this work is to determine paraquat adsorption capacity of zeolite NaX and Al-MCM-41. All adsorbents were synthesized by hydrothermal method using rice husk silica. For Al-MCM-41, aluminum (Al) was added to the synthesis gel of MCM-41 with Al content of 10, 15, 20 and 25 wt%.