Water-Mediated Green and Efficient Synthesis of Bis(Indolyl)methanes Using Ammonium Iron(II) Sulfate

An efficient protocol for the synthesis of symmetrical 3,3’-bis(indolyl)arylmethanes catalyzed by green and easily available ammonium iron(II) sulfate (Mohr’s salt) has been developed in “green” water solvent afforded in excellent yield.

Novel draw solutes of iron complexes easier recovery in forward osmosis process

Forward osmotic (FO) membrane is a new process for producing fresh water from salt water. The study of draw solute is essential in the development and application of FO technology; draw solution should be good at drawing water and easy at recovery. In this paper, three complex draw solutes such as ammonium iron (II) sulfate, ammonium iron (III) sulfate and ammonium iron (III) citrate with different concentrations were studied. The physical properties such as pH, conductivity and total dissolved solids (TDS) have simultaneously been investigated. The pH of most ammonium complexes was decreased whereas TDS increased with increasing of draw solution concentrations. We found that high water flux of these iron complexes was reported in the range of 8.88–11.24 LMH which was higher than the ammonium bicarbonate draw solution. In addition, more than 90% iron complexes draw solutions were recovered by NF-90 membrane, which plays an important role in the FO process to produce fresh water. This study provides direct evidence for the ability of permeate water from feed solution to draw solution, which shows the potential applications of iron complexes in FO process to produce fresh water from sea-, brackish or river water.

Crystallinity depends on choice of iron salt precursor in the continuous hydrothermal synthesis of Fe–Co oxide nanoparticles

A series of Fe–Co oxide nanoparticles (NPs) were prepared by a continuous hydrothermal method using iron nitrate and ammonium iron citrate as alternative iron precursors.

α-NH4Fe(HAsO4)2

The title compound α-ammonium iron(III) bis[hydrogen arsenate(V)], α-NH4Fe(HAsO4)2(or poly[ammonium bis(μ-hydrogen arsenato)ferrate(III)], {NH4[Fe(HAsO4)2]}n), synthesized hydrothermally, is isostructural with NH4Fe(HPO4)2. Condensation of the hydrogen arsenate groups with FeO6coordination octahedraviacommon corners results in an overall three-dimensional framework containing interconnected channels parallel to thea-,b-andc-axis directions. The NH4+cations are located in three intersecting tunnels, which is promising as an ion exchange. Hydrogen bonding of the types O—H...O and N—H...O consolidates the packing of the structure. The distortion of the coordination polyhedra is analyzed by means of the effective coordination number and distortion indices. Structural relationships with other compounds of general formulaMIMIII[HXO4)]2(X= P, As) are discussed.