about
15 min. The resulting suspension was mixed using a Homogenizer for 5 min. The next step started with continuous mixing of ingre- dients at room temperature for about 1 h followed by the addition of a solution of 0.6 g coagulation agent in nitric acid over 10 min until the mixture reached a pH value of 2. In this manner, a gel was observed to form as a result of changing the viscoelastic nature of the suspension from a Newtonian water-like fluid to a shear thin- ning paste-like gel. The temperature of the mixture was raised to