US 11,654,417 B2
Method for sulfonating sawdust to form modified sorbent
Muhammad Waqar Ashraf, Dhahran (SA)
Assigned to Prince Mohammad Bin Fahd University, Dhahran (SA)
Filed by Prince Mohammad Bin Fahd University, Dhahran (SA)
Filed on Oct. 6, 2022, as Appl. No. 17/960,843.
Application 17/960,843 is a continuation of application No. 16/737,554, filed on Jan. 8, 2020, granted, now 11,471,858.
Prior Publication US 2023/0048109 A1, Feb. 16, 2023
This patent is subject to a terminal disclaimer.
Int. Cl. B01J 20/30 (2006.01); B01J 20/28 (2006.01); C02F 1/28 (2023.01); C02F 1/58 (2023.01); B01J 20/32 (2006.01); B01J 20/24 (2006.01); B01J 20/22 (2006.01); B27L 11/06 (2006.01)
CPC B01J 20/3078 (2013.01) [B01J 20/28016 (2013.01); B01J 20/28059 (2013.01); B01J 20/3021 (2013.01); B01J 20/3071 (2013.01); B01J 20/3231 (2013.01); B01J 20/3242 (2013.01); B01J 20/3248 (2013.01); C02F 1/288 (2013.01); C02F 1/58 (2013.01); B01J 20/22 (2013.01); B01J 20/24 (2013.01); B01J 20/305 (2013.01); B27L 11/06 (2013.01)] 11 Claims
 
1. A method of sulfonating sawdust to form a modified sawdust sorbent comprising:
mixing the sawdust with sulfuric acid to form a sulfonating mixture,
heating the sulfonating mixture at 100 to 200° C. to form a mixture comprising a liquid and a sulfonated sawdust,
filtering and/or decanting the mixture to isolate the sulfonated sawdust,
washing and drying the sulfonated sawdust at 50 to 150° C. to form a dried sawdust,
treating the dried sawdust with a hydrogen peroxide solution to form a peroxide-treated sawdust,
washing and drying the peroxide-treated sawdust at 50 to 150° C. to form a sulfonated and oxidized sawdust, and
milling and sieving the sulfonated and oxidized sawdust to form the modified sawdust sorbent,
wherein the modified sawdust sorbent has a dye adsorption capacity of 20 to 25 mg of dye per g of sorbent at 25 to 45° C.