Minia University Faculty of Engineering Chemical Engineering Department

Minia University Faculty of Engineering Chemical Engineering Department Course Title: Unit Operation II Course Code: CHE 321 Third Year Course Coordinator: Prof. Dr. Mohammad Shawky Lecture No. 7

Physico-Chemical Studies on Adsorbent Physical Analysis: (1) Pore size distribution Porosity (4) Total pore volume (5) Particle shape (6) Moisture content (7) PH determination (8)Total surface area

Physico-Chemical Studies on Adsorbent Physical Analysis: (1) Pore size distribution 3) Porosity (4) Total pore volume (5) Particle shape (6) Moisture content (7) PH determination (8)Total surface area

Physico-Chemical Studies on Adsorbent Porosity Particle porosity Bed porosity

Physico-Chemical Studies on Adsorbent Porosity Particle porosity Bed porosity

Physico-Chemical Studies on Adsorbent (3) Porosity : Types of porosity: 1. Particle porosity (εp): εp= fraction of internal voids = particle porosity =voidage

Physico-Chemical Studies on Adsorbent Porosity Particle porosity Bed porosity

Physico-Chemical Studies on Adsorbent Porosity Particle porosity Bed porosity

Physico-Chemical Studies on Adsorbent (3) Porosity : Types of porosity: 2. Bed porosity (εb):

Physico-Chemical Studies on Adsorbent 2. Bed Porosity (εb): Porosity can be measured using Mercury Porosimetry, for pith initially dried in a vacuum at 50ºC for 8 hr. The surface area of the pith was measured on Y uasa surface area apparatus (BET method). Pore volumes and average pore radius of the pith was determined on a Carlo-Erba mercury porosimater (Model 1520).

Physico-Chemical Studies on Adsorbent Physical Analysis: (1) Pore size distribution 3) Porosity (4) Total pore volume (5) Particle shape (6) Moisture content (7) PH determination (8)Total surface area

2. 1 Physico-Chemical Studies on Adsorbent Physical Analysis: (1) Pore size distribution Porosity (4) Total pore volume (5) Particle shape (6) Moisture content (7) PH determination (8)Total surface area

Physico-Chemical Studies on Adsorbent Physical Analysis: (4) Total pore volume (VP, cm 3/g or m 3/kg or ml/g) The characteristics of some local natural and activated clay are shown in Table (3).

Physico-Chemical Studies on Adsorbent Table (3): Surface characteristics of raw and some activated clays. Sample SBET (m 2. g-1) Vm VP (ml. g-1) Untreated clay 65 15 0. 143 44 Pretreated clay 112 25. 62 0. 083 32. 7 Activated clay by 1 N HCl - 30 min. 75 17 0. 0124 33. 1 60 13. 8 0. 133 44. 3 1 N HCl - 90 min. (Å)rp

Physico-Chemical Studies on Adsorbent Table (3): Surface characteristics of raw and some activated clays. Sample SBET (m 2. g-1) Vm VP (ml. g-1) 1 N HCl - 90 min. 60 13. 8 0. 133 44. 3 1 N HCl - 180 min 40 9 0. 107 53. 5 25 0. 314 57. 6 2 N HCl - 30 min. 109 (Å)rp 2 N HCl - 90 min 115 26. 34 0. 326 56. 7 2 N HCl - 180 min 127 29. 0 0. 278 43. 8

Physico-Chemical Studies on Adsorbent Physical Analysis: (1) Pore size distribution ) Porosity (4) Total pore volume (5) Particle shape (6) Moisture content (7) PH determination (8)Total surface area

Physico-Chemical Studies on Adsorbent Physical Analysis: (1) Pore size distribution Porosity (4) Total pore volume (5) Particle shape (6) Moisture content (7) PH determination (8)Total surface area

Physico-Chemical Studies on Adsorbent Physical Analysis: (5) Particle shape Adsorbent may be: a) Powder form--------Cylindrical Shape b) Granular form-------Spherical Shape

Physico-Chemical Studies on Adsorbent Physical Analysis: (5) Particle shape 1. Cylindrical Shape: The surface area of the cylindrical shape is , and the volume is d: is diameter of the cylinder; L: is length of the cylinder; and : constant. dp L

Physico-Chemical Studies on Adsorbent Physical Analysis: (5) Particle shape 2. Spherical Shape: The surface area of the sphere is , and the volume is

Physico-Chemical Studies on Adsorbent Physical Analysis: (1) Pore size distribution Porosity (4) Total pore volume (5) Particle shape (6) Moisture content (7) PH determination (8)Total surface area

2. 1 Physico-Chemical Studies on Adsorbent Physical Analysis: (1) Pore size distribution Porosity (4) Total pore volume (5) Particle shape (6) Moisture content (7) PH determination (8)Total surface area

Physico-Chemical Studies on Adsorbent Physical Analysis: (6) Moisture content Under humid conditions, adsorbents may adsorb perhaps 25 to 30% moisture, over a few months, and still appear dry. For many purposes, particularly in wastewater treatment, the moisture content does not adversely affect the adsorbent performance, but merely act as a dilute, so that an additional quantity of adsorbent is required to provide the desired dry weight. Moister content of local natural clay = 7. 9 ± 0. 25% measured after sample dried at 105 ºC for 12 hours.

Physico-Chemical Studies on Adsorbent Physical Analysis: (1) Pore size distribution ) Porosity (4) Total pore volume (5) Particle shape (6) Moisture content (7) PH determination (8)Total surface area

2. 1 Physico-Chemical Studies on Adsorbent Physical Analysis: (1) Pore size distribution Porosity (4) Total pore volume (5) Particle shape (6) Moisture content (7) PH determination (8)Total surface area

Physico-Chemical Studies on Adsorbent Physical Analysis: (7) PH determination For natural clay PH measured by the following procedure: 1. Suspension containing 1 g of natural clay in 25 ml of distilled water. 2. After 48 h aging, the PH values of different clay suspensions were measured by means of accurate PH meter.