The HAps obtained by the two methods displayed different characteristics in their crystallinity, morphology, composition, surface area and basicity
. HAp derived from direct calcination had lower crystallinity, lower grain size, and higher surface area than the HAp provided by acid base treatment, which correlated with a higher surface basicity
On the other hand, for Ho promoted catalysts, the increase in CO2 conversion was credited to the relatively higher basicity
of these catalysts than un- promoted catalyst (Fig.
Thus, it can be stated the constants denoting acidity and basicity
obtained with Gutmann's approach in Table 4 are only approximate values, at least in this study.
Increase in natural basicity
of surface of rich with montmorillonite samples or formation of additional basic sites (O- atoms) by high activation temperature of catalysts were the reasons of growth of MBOH conversion.
From table 2, Adding fluoride (F) to PS will decrees PA (Proton Affinity) following the order m less than p less than o , chloride (Cl) ) will decrees PA following the order m less than o less than p , methyl (CH3) will increase PA following the order o less than m less than p , adding groups as (O-O-Phenyl) will increase PS basicity
, (O-CH3-O-Phenyl) will decrease PS basicity
and adding groups as (O-(C=O)-O-Phenyl) will decrease PA but less than (O-O-Phenyl) do.
In this study, various amounts of tricalcium silicate were added to CPC to enhance its basicity
. [Ca.sub.3]Si[O.sub.5] was selected instead of Ca[(OH).sub.2] because it has lower solubility.
The presence of surface basicity
(Table 5) suggests that fresh biochars will also have some capacity to retain anions in soil; however, the surface basicity
may decrease and eventually disappear with progressive oxidation of biochar (Cheng et al.
Evaluation of the basicity
of the slag melt is essential for determining the possibilities of interaction of the component of the slag with each other and, most importantly, with the components of the contacting phases (metallic and gas).
A volatile alkali, such as ammonium hydroxide, is added to perms which dissipates during the process to reduce the basicity
of the solution.
Scales of Lewis basicity
have been established from experimental complexation enthalpies toward [BF.sub.3] and a number of other Lewis acids.
Similar molecules and ions could have potential applications in areas such as catalysis and the fabrication of magnetic switches; in addition, they are expected to exhibit interesting gas-phase acidity and/or basicity
TABLE 1 - COAGULANT CHANGE: ALUM TO ACID ALUM %TOC Removal % TOC Removal %TOC Removal Required With Alum With Acid Alum Plant 1 40 25 52 Plant 2 40 25 60 Plant 3 35 31 47 Plant 4 25 19 27 TABLE 2 - THEORETICAL EFFECTS ON ALKALINITY WITH CHEMICAL ADDITION Alkali Alkalinity Increase [*] Quicklime (CaO) 1.78 Hydrated lime (Ca[(OH).sub.2]) 1.35 Caustic soda (NaOH) 1.28 Soda ash ([Na.sub.2][CO.sub.3]) 0.94 Coagulant Alkalinity Decrease [**] Alum or aluminum sulfate 0.50 (dry basis) Ferric Chloride (dry basis) 1.0 Ferric Sulfate (dry basis) 1.0 Aluminum Chloride (as 5.6% AI) 0.312 Low Basicity
PACI (as 5.3% AI) 0.265 Mid Basicity
PACI (as 5.3% AI) 0.147 High Basicity
PACI (as 5.3% AI) 0.088 (*)Theomtical increase expressed as [CaCO.sub.3]/ppm of alkali added.