Preparation of high concentration polyaluminum chloride with high content of Alb or Alc

Abstract

A novel membrane distillation concentration method was used to prepare high concentration polyaluminum chloride (PACl) with high content of Al b or Al c . 2.52 mol/L PACl 1 with 88% Al b and 2.38 mol/L PACl 2 with 61% Al c were successfully prepared. Three coagulants, AlCl 3 , PACl 1 and PACl 2 were investigated on their hydrolysis behavior and speciation under different conditions. The effects of pH and dilution ratio on Al species distribution were investigated by ferron assay. Experimental result showed that pH had a significant effect on Al species distribution for the three coagulants. Dilution ratio had little effects on Al b and Al c distribution in whole dilution process except the beginning for PACl 1 and PACl 2 . The results indicated that transformation of Al depends largely on their original composition. AlCl 3 was the most unstable coagulant among these three coagulants during hydrolysis process. PACl 1 and PACl 2 with significant amounts of highly charged and stable polynuclear aluminum hydrolysis products were less affected by the hydrolysis conditions and could maintain high speciation stability under various conditions.

Non-solvent Flux Augmentation of an LDPE-Coated Polytetrafluoroethylene Hollow Fiber Membrane for Direct Contact Membrane Distillation

“…The modified PTFE HF membrane was tested in the DCMD experiment in which sodium chloride was introduced in the feed solution with increasing feed temperature. Feed temperature is one of the parameters that has been widely investigated to determine the MD process’s success in achieving the highest permeate flux . In general, the exponential increase in water permeation flux can be obtained by increasing the temperature of the feed solution .…”

“…Feed temperature is one of the parameters that has been widely investigated to determine the MD process's success in achieving the highest permeate flux. 49 In general, the exponential increase in water permeation flux can be obtained by increasing the temperature of the feed solution. 50 E-3 was chosen for the wettability study, where feed temperature was varied from 60 to 80 °C at 10 °C increments to remove salt (synthetic sodium chloride).…”

Photocatalytic performance and dispersion stability of nanodispersed TiO2 hydrosol in electrolyte solutions with different cations

“…Because of the flocculation effect of the hydrolysates of aluminum, they have a strong adsorption effect on impurities in water (Van Benschoten and Edzwald, 1990;Cao et al, 2016;Tang et al, 2015). The solution pH plays an important role on the hydrolysis process of aluminum (Zhao et al, 2009), i.e. the at lower pH (<6), the amount of monomer aluminum and oligomeric state aluminum increase with the decrease of pH, and the amounts of middle and high polymer state aluminums are revised.…”

Study on the Characterization and Application of Poly-Silicate Magnesium Ferric Sulfate Borate (PFMSSB)

“…These traditional flocculants have a common defect that it is difficult to control the formation of metal hydrolysis species. In order to avoid it, a lot of inorganic polymeric flocculants(IPF) such as poly-aluminum chloride(PAC), poly-ferric chloride(PFC) and poly-ferric sulfate(PFS) have been developed [5][6][7][8][9]. However these polymeric flocculants can not meet the need, more studies focused on improving the performance of IPF.…”