The revenue receipts of the Union Government are the funds that it receives on a regular basis, primarily through taxes and other sources. Option 1, corporate tax receipts, refers to the taxes collected from corporations. Option 2, dividends and profits, refers to the income generated by government-owned companies and other investments. Option 4, interest receipts, refers to the interest earned on loans and investments made by the government.

Option 3, disinvestment receipts, is not a component of revenue receipts. Disinvestment refers to the selling of government-owned assets, such as shares in public sector enterprises. While disinvestment does generate funds for the government, it is classified as a capital receipt rather than a revenue receipt.

Therefore, option 3 is the correct answer as it is not a component of revenue receipts of the Union Government. The other options all represent different sources of revenue for the government.