Deinking the mixed office waste paper with surfactants and cellulase enzyme at neutral pH

Effect of surfactants and cellulose enzyme on deinking mixed office waste paper was studied. To that end, a combination of waste paper accounting for 60% printing paper and 40% copy paper was applied. Then, samples of paper pulp were deinked using four types of cellulose, Surfactant and sodium silicate. The types and the proportion of the chemicals used in the study are as follows: a) Surfactant, b) Cellulase, 0% and 0/6 % were added based on the weight of paper pulp together with a surfactant. c) Sodium silicate with the fix amount of 0/3% of the weight of the paper pulp was used in the process. Different samples of paper pulp influenced by 24 compounds comprising enzymes and chemicals were deinked and the efficiency of the materials was calculated after the process. Following that, all the paper pulp samples were turned into hand-made papers and then indices such as brightness, dirt (quality and quantity of dirt) were studied. The results showed that the type of surfactant and cellulose enzyme affect brightness, dirt index and deinking efficiency.Maximum brightness was with nonyl phenol ethoxylate and fatty alcohol ethoxylate without cellulose enzyme.Minimum dirt index was with nonyl phenol ethoxylate and cellulose enzyme.Also, using nonyl phenol ethoxylate and fatty alcohol ethoxylate result in maximum deinking efficiency.