Main Idea

Not all paper is recycled the same way; some paper requires complex chemical treatments before it can be made into usable recycled paper. For this reason, we must not simply recycle our paper, but carefully choose what kinds of paper to buy in order to minimize environmental waste.

Background

We recycle paper to reduce environmental waste. We cannot solve our environmental problems, however, by recycling any kind of paper. Not all paper is created equal. Recycling some types of paper requires bleach to make it white, and certain bleaching agents are harmful to the environment. By experimenting with different kinds of paper and bleaching agents, we can determine what kinds of paper recycle best and are the most environmentally friendly.

Learning Objectives

• Understand the chemical processes involved in recycling paper.
• Recognize the environmental issues in using and recycling different kinds of paper.

Time

1 & 1/2 hours

Introducing the Concept

Discuss with the students the basic process involved in recycling paper. Ask them what they think the paper might look like after it is recycled. Supply them with different kinds of non-recycled paper including regular writing paper, magazine paper and thick dark construction paper. Ask them to describe what each of the papers might look like after being recycled. Next, supply them with various types of recycled paper including white, off-white and paper containing fibre. (You may even want to provide them with parts of cereal boxes). Ask them to match the recycled paper with the paper it came from.

Materials

Raw Materials

• Papers
• glossy paper: flyers, magazines
• regular paper: writing paper, scratch pads, envelopes
• newsprint
• pressed dried leaves, flowers or plants (optional)

Coloring Agents

• bleach (1/4 cup per batch of paper)
• hydrogen peroxide
• water-based food coloring

Equipment

• blender
• water
• wooden screen 20 cm x 25 cm or larger (pre-made by stapling window-screen material to a wooden picture frame)
• fairly large dishpan for mixing paper pulp
• cut-up old sheets or flat cotton rags (large enough to cover the screen)
• rolling pin
• flat board or glass sheet

Hands-On

Make your own recycled paper, using one of three types of paper.

1. Get the students to separate the paper into piles of glossy, regular and newsprint, and then choose the type of paper they will use for recycling.
2. Tear the paper into small pieces and place these in the blender with the water. Let the paper soak for about 10-15 minutes.
3. Blend the paper until it’s a smooth pulp.
4. Pour about 12 cm pulp into the tub, adding a little water if it is too thick.
5. Dip the frame into the pulp mixture; holding it level, sift it back and forth until there is an even layer of pulp about 3 cm thick.
6. Lift the frame out of the pan and let the water drain out. If the pulp clumps together or has holes in it, dip the frame back in the pan and sift it again.
7. If the students wish, they can press the leaves or flowers into the pulp so that they are partially covered and will stay in the paper.
8. Lay the piece of cloth over the pulp and frame. Press down gently to squeeze out excess water.
9. Lay a few pieces of newspaper down on a table. Carefully turn the frame upside down onto the newspaper and lift off the frame. Cover the pulp with another rag so that the paper is sandwiched between two pieces of cloth.
10. Press out water by rolling the cloth sandwich with the rolling pin until it is quite thin.
11. Carefully peel off the top cloth. Place the board or glass sheet on top of the wet paper and flip it so that the remaining piece of cloth can be carefully removed.
12. The students may repeat the procedure for each person in their group, so that they can each have their own sheet of recycled paper. They may want to experiment with dye and stripping agents (food coloring and bleach) as they proceed.

Minds-On

• Have the groups discuss the recycling process and results with each other.
• Did they use the same type of paper as another group? If not, were there any differences in the paper produced?

Teaching Tips

• This activity can get messy and it requires a lot of space. Plan for some extra cleanup time.
• With very young students, you may want to oversee the bleaching process.
• When blending the paper and water, make sure there's enough water to keep the blender from jamming.

Interconnections

Explore the history of paper and its predecessors. You might begin with the use of stone and wax tablets, and discuss the benefits and drawbacks of these materials for recording information. Next, investigate the use of papyrus and eventually paper. If you are interested in discussing current methods of recording information, you might talk about the electronic highway and CD ROM technology, and their pros and cons. Have the students write a story about a school either 2000 years ago or 2000 years in the future and the kinds of school supplies students would use there.

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This activity copied from APASE of Vancouver, Canada, which has regrettably disappeared from the Web.

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