Download e-book for kindle: Characterization and Chemical Modification of the Silica by E.F. Vansant

By E.F. Vansant

ISBN-10: 0444819282

ISBN-13: 9780444819284

Oxide floor fabrics are customary in lots of purposes, particularly the place chemically changed oxide surfaces are concerned. certainly, in disciplines reminiscent of separation, catalysis, bioengineering, electronics, ceramics, etc., changed oxide surfaces are vitally important. In all instances, the information in their chemical and floor features is of serious significance for the knowledge and eventual development in their performances. This ebook studies the most recent thoughts and approaches within the characterization and chemical amendment of the silica floor, proposing a unified and state of the art method of the suitable research concepts and amendment strategies, protecting a thousand references built-in into one transparent proposal.

Show description

Read Online or Download Characterization and Chemical Modification of the Silica Surface PDF

Similar chemical engineering books

Download e-book for iPad: Perry's Chemical Engineers' Handbook. Section 25 by Oliver W. Siebert

Now in its 8th version, Perry's Chemical Engineers' instruction manual bargains unequalled, up to date assurance of all facets of chemical engineering. For the 1st time, person sections can be found for buy. you can now obtain in simple terms the content material you would like for a fragment of the cost of the full quantity.

Get Colloids in Biotechnology (Surfactant Science) PDF

Colloids express nice strength in a wide selection of purposes, together with drug supply and clinical imaging, and the layout and fabrication of colloid structures has attracted significant curiosity within the examine group. Colloids in Biotechnology describes advancements within the box of biotechnological functions long ago decade and bridges the distance among those examine efforts and commercially plausible concepts.

Download e-book for kindle: Separation Process Principles with Applications Using by J. D. Seader, Ernest J. Henley, D. Keith Roper

Separation method rules with functions utilizing strategy Simulator, 4th variation is the main finished and up to date therapy of the key separation operations within the chemical undefined. The 4th version specializes in utilizing approach simulators to layout separation techniques and prepares readers for pro perform.

Additional info for Characterization and Chemical Modification of the Silica Surface

Sample text

21 Condensation takes place in such a way as to maximize the number of Si-O-Si bonds and minimize the number of terminal hydroxyl groups by internal condensation. Thus rings are quickly formed to which monomers add, creating three-dimensional particles. ~2 By a variation of pH and salt addition the particle aggregation into secondary particles (A) or further particle growth (B) is controlled. Thus the particle size and pore structure of the silica is determined. Iler discerned three pH domains in the polymerization process.

0 for N 2 at 77 K) Based on the above general principles, quite a number of models have been developed to estimate pore size distributions. ). Even the so-called 'modelless' calculation methods do need a pore model in the end to convert the results into an actual pore size distribution. Very often, the exact pore shape is not known, or the pores are very irregular, which makes the choice of the model rather arbitrary. The model of Barett, Joyner and Halenda 34 (BJH model) is based on calculation methods for cylindrical pores.

H! --~ ~ SiOH H Step 1 + ~ H+ 1 "" .. 6b Proposed mechanism for the hydronium catalyzed hydrolysis of silane esters. 2 Condensation Silicic acid molecules condense to form siloxane bonds, with release of water (A). 6 --Si-OH + HO-Si- ~ -Si-O-Si- + 1t20 (A) Condensation may also proceed by the reaction of the alkoxysilane with a silanol group, releasing an alcohol (B). - Si-OH + RO-Si-- --, -- S i - O - S i - + ROH (B) The condensation may be acid or base catalyzed. Osterholz and Poh115 concluded that acid catalyzed condensation proceeds through an SN2-Si type mechanism, while base catalyzed condensation is less well understood.

Download PDF sample

Characterization and Chemical Modification of the Silica Surface by E.F. Vansant

by Daniel

Rated 4.28 of 5 – based on 33 votes